4,785 results on '"Population viability analysis"'
Search Results
2. Accounting for multiple uncertainties in a decision-support population viability assessment
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Christensen, Erica M., Lawson, Abigail J., Rivenbark, Erin, London, Paula K., Castellanos, David, Culbertson, Jan C., DeMay, Stephanie M., Eakin, Carly, Pearson, Luke S., Soileau, Karen, Waddle, Hardin, and McGowan, Conor P.
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- 2024
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3. Effect of capitulum position and weevil infestation on seed production of threatened monocarpic perennial, Cirsium pitcheri
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Gijsman, Finote, Havens, Kayri, and Vitt, Pati
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- 2020
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4. A refined population and conservation assessment of the elusive and endangered northern tiger cat (Leopardus tigrinus) in its key worldwide conservation area in Brazil
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de Oliveira, Tadeu G., Lima, Breno C., Fox-Rosales, Lester, Pereira, Renata S., Pontes-Araújo, Elienê, and de Sousa, Alana L.
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- 2020
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5. Securing black lion tamarin populations: improving habitat-based inputs and risks for population viability analysis to inform management decisions.
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Forero-Sánchez, Francy, Rezende, Gabriela Cabral, Valladares-Pádua, Cláudio, Vannucchi, Fabio Stucchi, Jerusalinsky, Leandro, Pacca, Luciana, and Traylor-Holzer, Kathy
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FRAGMENTED landscapes ,ENDANGERED species ,POPULATION viability analysis ,LIFE history theory ,SIMULATION software ,WATERSHEDS - Abstract
Wild populations across the globe face an escalating risk of decline and potential extinction due to a variety of threats. Key among these are habitat loss and degradation, which results in smaller, isolated populations that are vulnerable to stochastic effects. The Endangered black lion tamarin (Leontopithecus chrysopygus) survives in 17 fragments of the Atlantic Forest within the Paranapanema River basin, in southeast Brazil, with an estimated 2,255 individuals. Life history and threat data from the 2005 Population Viability Analysis (PVA) for this species were updated and augmented, including new estimates of environmental resistance factors present in, or projected for, their habitat. Notably, improved estimates of carrying capacity for this species were developed using a plant-based energetic model. Climate change and fire risk data were incorporated to project future carrying capacity, and habitat connectivity supported estimates of black lion tamarin dispersal across this fragmented landscape. The resulting population viability projections using Vortex simulation software identify core subpopulations with low extinction risk and high gene diversity, as well as smaller subpopulations with low long-term viability, highlighting the need for targeted conservation strategies across the fragmented metapopulation. [ABSTRACT FROM AUTHOR]
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- 2025
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6. Integrating Conservation and Community Engagement in Free-Roaming Cat Management: A Case Study from a Natura 2000 Protected Area.
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Luzardo, Octavio P., Hansen, Andrea, Martín-Cruz, Beatriz, Macías-Montes, Ana, and Travieso-Aja, María del Mar
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POPULATION viability analysis , *FERAL cats , *COMMUNITY involvement , *BIODIVERSITY conservation , *PROTECTED areas - Abstract
Simple Summary: This study evaluates the effectiveness of a Trap–Neuter–Return (TNR) program implemented in La Graciosa, a Natura 2000 protected area in the Canary Islands, to manage its free-roaming cat population. The campaign achieved an 81.4% sterilization rate in urban areas within three days, significantly reducing the cats' reproductive potential and contributing to an alleviation of predation pressures on vulnerable species. Active community involvement played a critical role in the campaign's success, yet administrative restrictions and opposition from conservation groups limited its scope. A Population Viability Analysis (PVA) revealed that while high sterilization rates can reduce populations, achieving the necessary 93–95% threshold is essential for long-term success. The study underscores the need for adaptive, context-specific management strategies that integrate TNR with complementary measures like adoption or relocation and highlights the challenges posed by regulatory and societal factors in balancing biodiversity conservation with humane management practices. La Graciosa, a Natura 2000 site in the Canary Islands, faces substantial conservation challenges, including a large free-roaming cat population that threatens the island's native biodiversity. In July 2024, a Trap–Neuter–Return (TNR) campaign achieved an 81.4% sterilization rate within urban areas, highlighting TNR's short-term effectiveness in reducing reproductive potential and, consequently, mitigating predation pressures primarily through the prevention of new litters and reduced reproductive activity in cats. The campaign's success relied heavily on the active involvement of the local community, who assisted with identifying, trapping, and monitoring free-roaming cats, thereby facilitating a high sterilization rate. However, administrative restrictions hindered access to peri-urban zones, leaving essential population clusters unsterilized and limiting the campaign's overall scope. Additionally, strong opposition from conservation groups, amplified by extensive media coverage, halted the project prematurely, reducing the effective sterilization rate to 69.3% within three months. Population Viability Analysis (PVA) suggests that achieving high sterilization rates could lead to population reduction over time; however, the inability to access all population segments and to reach the ideal 93–95% sterilization threshold limits TNR's potential as a long-term standalone solution. Our findings underscore the need for adaptive, context-specific management frameworks in ecologically sensitive areas that integrate TNR with complementary measures, consider regulatory barriers, and value community involvement. This case study provides crucial insights for policymakers and conservationists seeking to balance biodiversity conservation with humane management practices in protected areas. [ABSTRACT FROM AUTHOR]
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- 2025
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7. Targeted nest predator management and zoo-bred supplementation in a Regent Honeyeater (Anthochaera phrygia) breeding event.
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Crates, Ross, Roderick, Mick, Maute, Kimberly, Menke, Lisa, Hancock, David, Kyte, Robert, Berry, Lainie, Paasila, Timothy, Breckenridge, Max, Grenadier, Lucas, Hynson, Robert M. G., Schmelitschek, Emily, Stevens, Kara, Van Sluys, Monique, and Heinsohn, Robert
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POPULATION viability analysis , *PREDATOR management , *BIRD habitats , *LAND settlement patterns , *PATTERNMAKING , *NEST predation - Abstract
Nomadic species are challenging to conserve, because their high mobility and irregular settlement patterns make it difficult to implement targeted conservation actions. Here, we report on the first sustained attempt to protect nests of Critically Endangered Regent Honeyeaters from predation and to release zoo-bred birds into a wild breeding event. During the 2023 breeding season, targeted culling of known nest predator species within the area of 10–12 wild breeding pairs within Capertee National Park was associated with a daily nest survival rate of 97.9%. This equated to an overall nest success rate of 48.6% and resulted in the fledging of 18 juveniles from nine nests – double the average nest success rate from 2015, 2016 and 2017 (24.1%) when Regent Honeyeaters bred in the same location. Population viability analysis indicates nest protection alone could slow the rate of population decline, but its effectiveness depends on the proportion of nests that can be located and protected each year. Fourteen zoo-bred Regent Honeyeaters were released approximately half way through the breeding event. Seven zoo-bred birds were confirmed alive 5 weeks post-release, but no zoo-bred birds released in 2023 attempted to breed in this year. Although our sample is small and prone to stochastic effects, we provide non-experimental evidence that nest predator management can play a key role in boosting recruitment of juvenile Regent Honeyeaters to the wild population. In combination with the reintroduction of zoo-bred birds and habitat restoration, nest predator management can help prevent imminent extinction of the Regent Honeyeater. [ABSTRACT FROM AUTHOR]
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- 2025
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8. State of knowledge of the population of the vaquita (Phocoena sinus) from the Upper Gulf of California: a bibliometric analysis.
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Arreguín-Sánchez, Francisco, Zetina-Rejón, Manuel J., Vergara-Solana, Francisco Javier, Del Monte-Luna, Pablo, Rodríguez-Fuentes, Marian, Arreguín-Rodríguez, Gabriela J., Medina-Contreras, Diana, and Sánchez-Velasco, Laura
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BIBLIOMETRICS ,SCIENTIFIC knowledge ,HARBOR porpoise ,FISHERIES ,ENDEMIC species ,POPULATION viability analysis - Abstract
The state of scientific knowledge about the vaquita, Phocoena sinus , is presented, a critically endangered endemic species of the Upper Gulf of California, Mexico. Several bibliographic repositories were explored, selecting Web of Science because it considers the Science Citation Index as a selection criterion. A bibliometric and bibliographic analysis of the literature was carried out. A network of associations was built based on the co-occurrence of sets of keywords, which reflect the relevance of the research topics discussed. Two sets stand out: population and conservation. Unaddressed topics are also identified, such as trophic interdependencies, ecosystem, effects of the environment and climate patterns. Regarding the population, topics such as changes in abundance, vulnerability, distribution and current habitat have been addressed. In terms of conservation, the monotonic decrease in the size of the population stands out, the management aimed at stopping this decrease and the interaction with commercial and illegal fishing. In conclusion, the measures adopted have not been effective, given that the vaquita population continues to decline. There are failures in the application of regulations, insufficient monitoring and surveillance, unregistered captures, illegal fishing and the limited participation of human communities in the design and implementation of the regulations, perceiving damages and lack of interest in compliance with the regulations and proposed measures. Beyond the knowledge gained, research is needed to answer a key question: are current habitat and ecosystem conditions suitable for the vaquita population to recover? The answer to this question requires different and even currently non-existent knowledge. [ABSTRACT FROM AUTHOR]
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- 2025
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9. Zoos must embrace animal death for education and conservation.
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Clauss, Marcus, Roller, Marco, Bertelsen, Mads Frost, von Rohr, Claudia Rudolf, Müller, Dennis W. H., Schiffmann, Christian, Kummrow, Maya, Encke, Dag, Ferreira, Sam, Duvall, Ethan S., Maré, Celesté, and Abraham, Andrew J.
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POPULATION viability analysis , *WILD horses , *ATTITUDES toward the environment , *WILDLIFE reintroduction , *PARENTAL behavior in animals , *ANIMAL welfare laws , *ANIMAL laws - Published
- 2025
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10. A Metapopulation Model to Assess Water Management Impacts on the Threatened Australian Lungfish, Neoceratodus forsteri.
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Todd, Charles R., McDougall, Andrew J., Raymond, Scott M. C., Hale, Robin, Brown, Timothy R., Koehn, John D., Wootton, Henry F., Brooks, Steven G., Kitchingman, Adrian M., Espinoza, Tom, Fanson, Benjamin G., Kind, Peter K., Marshall, Sharon M., and Roberts, David T.
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POPULATION viability analysis , *LIFE history theory , *POPULATION forecasting , *STREAMFLOW , *WATERSHEDS - Abstract
The Australian lungfish, Neoceratodus forsteri, is one of the world's oldest vertebrate lineages, with a slow life-history and threatened status, requiring immediate conservation efforts. The main threats to lungfish populations are degradation and availability of key macrophyte habitats, water regulation and flow modification. As this long-lived species (at least 77 years) has delayed maturity (mature at 10 years), field monitoring alone will not be enough to inform the challenge of ensuring sustainable populations. A stochastic metapopulation model was developed for the Burnett River (Southeast Queensland, Australia), an important habitat for the lungfish that is a highly regulated system with extensive water infrastructure. The model consists of three interacting populations, where the ecology and biology of the species were translated into an 80-year-class population projection matrix for each population, each with post-development streamflow, habitat and movement rules. The model highlights the longer-term interaction between dams and stream flows on habitat availability and subsequent recruitment. Through a pre-development streamflow, we quantify the impact of high regulation and development on the lungfish population in the Burnett River: a minor decline in the upstream population (e.g., 9.8% decline), a large decline in the middle population (64.2% decline), virtually no change in the downstream population (e.g., 1.2% decline) and a moderate decline in the overall metapopulation (e.g., 22.3% decline). The loss of spawning and feeding habitat remains the main reason for population decline, with implications that the loss will lead to greater pressure on remaining downstream habitat due to combined flow and dam effects and, in turn, to extended periods of recovery of spawning habitat. Our modeling approach substantially advances conservation management of this species, as it can be adapted to suit other populations in other river systems and used to test sensitivity to recovery actions. [ABSTRACT FROM AUTHOR]
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- 2025
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11. Inflated predictions from a flawed model influenced the decision to deny federal protection for the gopher tortoise
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Loope, Kevin J., Akçakaya, H. Resit, and Shoemaker, Kevin T.
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- 2024
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12. To mix, or not to mix?: Mitogenomic insights for risk assessment of an interpopulation translocations of the critically endangered European mink.
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Skorupski, Jakub, Seebass, Christian, Festl, Wolfgang, Kiseleva, Natalia, Śmietana, Przemysław, and Marinov, Mihai
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GENETIC variation , *AMERICAN mink , *OUTCROSSING (Biology) , *HAPLOTYPES , *LIVESTOCK breeding , *POPULATION viability analysis - Abstract
This study provides a comprehensive, population‐scale analysis of the mitogenome of the critically endangered European mink, Mustela lutreola, involving 52 individuals from Russia, Germany (conservation breeding stock), Romania, and France‐Spain. Significant mitogenomic diversity was identified within the previously presumed genetically homogenous French‐Spanish population, challenging concerns of inbreeding. Despite having lower nucleotide diversity (π = 0.00024) than the German (π = 0.00055) and Russian (π = 0.00048) populations, the French‐Spanish group exhibited impressive haplotype diversity (h = 0.9810) compared to Russian (h = 0.8727) and German (h = 0.7826) populations. Considering genetic diversity and uniqueness, the French‐Spanish population ranked highest in conservation importance, second only to the combined assessment of all other populations. The extensive population structuring identified two distinct haplogroups—the Central‐Eastern European and the Aquitaine‐Navarre—suggesting reconsideration of their conservation status. These findings guide tailored conservation strategies, emphasizing the need for careful interpopulation translocations to protect genetic diversity and prevent outbreeding depression. A decision algorithm for these translocations has been proposed. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Evaluating approaches for integrating species distributions in spatial conservation planning.
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Winiarski, Jason M., Shipley, Amy A., Fowler, Drew N., Palumbo, Matthew D., and Straub, Jacob N.
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SPECIES distribution , *HABITAT selection , *HABITAT conservation , *WILDLIFE conservation , *SCIENCE projects , *POPULATION viability analysis - Abstract
Map‐based decision support tools (DSTs) that use species distributions are an important means of identifying priority areas for conservation. The Wisconsin Waterfowl Habitat Conservation Strategy (WWHCS) uses a DST to identify priority ecological landscapes and watersheds to guide waterfowl habitat projects. The WWHCS DST relies on waterfowl habitat suitability layers derived through expert opinion in lieu of species distributions, a common approach in DSTs. Given the subjectivity of expert opinion, model‐driven species distributions such as those available from community science projects could provide more reliable information and better identify areas for waterfowl conservation. Here, we explore the application of relative abundance products available through the eBird Status and Trends project as an alternative to expert‐derived habitat suitability layers in the WWHCS DST. Our objectives were to compare seasonal species distributions from habitat suitability models (expert‐derived) and species distribution models (eBird‐derived) and determine whether differences influenced DST prioritizations. Correlations between expert‐ and eBird‐derived distributions were generally low to moderate for breeding and fall layers (ρ: −0.03–0.76), and lowest for spring (ρ: −0.49–0.72). There was also minimal agreement among top‐ranked ecological landscapes (40%) and watersheds (28%) between the two versions of the DST. Finally, we compare tradeoffs and suggest a model‐driven approach for the WWHCS DST. However, additional work validating eBird relative abundance against professional surveys and empirical studies evaluating waterfowl habitat selection and vital rates are important future considerations for the DST and waterfowl habitat conservation in Wisconsin. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Linking habitat and population viability analysis models to account for vegetation dynamics, habitat fragmentation, and social behavior of a metapopulation of Florida scrub-jays.
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Lacy, Robert C., Breininger, David R., Breininger, Daniel J., Savage, Anna E., Forsman, Anna M., Hoffman, Eric A., McGuffey, Stephen D., DeMeyer, David, and Mecklenborg, Todd
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POPULATION viability analysis ,FRAGMENTED landscapes ,VEGETATION dynamics ,RARE birds ,POPULATION dynamics ,FIREFIGHTING - Abstract
Population dynamics and viability are driven by interactions among habitat and species biology. The Florida scrub-jay (Aphelocoma coerulescens) is a declining and Federally Threatened bird species that requires mid-succession habitat of partly open soil surface with mid-height vegetation. This habitat is created and sustained in a dynamic state of vegetation growth and periodic natural (e.g., fire) or managed (e.g., mechanical clearing) disturbances. Florida scrub-jays once occupied open oak scrub habitats across much of peninsular Florida but have been reduced to a few regional metapopulations and scattered isolated remnant populations. Many of these populations are undergoing continuing decline as open scrub is either converted to residential development or transitions into closed pine and oak forests due to fire suppression. Long-term field studies have shown that breeding and survival rates are determined by the quality of the scrub habitat, with the demography influenced by and in turn mediating the social structure. Prior Population Viability Analyses (PVA) that included dependencies of demographic rates on habitat and social structure indicated that the east coast Florida metapopulations were fragmented into remnant protected patches that were too small and isolated to support long-term persistence, even if the remaining habitat area and quality was sustained. Moreover, recent modeling of habitat transitions under various proposed management schemes, in conjunction with implementation of Adaptive Resource Management (ARM), projected that the proportion of optimal habitat will continue to decline. In this study, we integrated these habitat projections within the PVA and found that the Brevard County mainland metapopulation is projected to decline toward extinction unless habitat quality, extent, and connectivity can be improved. Land managers have recently implemented new innovative methods for restoring optimal scrub habitat, identifying potential improvements in habitat connectivity of nearby populations, and translocation methods to increase and reinforce the demographic and genetic integrity of local populations. Our linked habitat-population models project that the combination of such habitat and population management actions can stabilize the metapopulation and achieve long-term viability. [ABSTRACT FROM AUTHOR]
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- 2024
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15. A modeling approach to forecast local demographic trends in metapopulations.
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Chambert, Thierry, Barbraud, Christophe, Cam, Emmanuelle, Chabrolle, Antoine, Sadoul, Nicolas, and Besnard, Aurélien
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LIFE history theory , *POPULATION viability analysis , *ANIMAL populations , *WILDLIFE monitoring , *WILDLIFE management - Abstract
Predicting animal population trajectories into the future has become a central exercise in both applied and fundamental ecology. Because demographic models classically assume population closure, they tend to provide inaccurate predictions when applied locally to interconnected subpopulations that are part of a larger metapopulation. Ideally, one should explicitly model dispersal among subpopulations, but in practice this is prevented by the difficulty of estimating dispersal rates in the wild. To forecast the local demography of connected subpopulations, we developed a new demographic model (hereafter, the two‐scale model) that disentangles two processes occurring at different spatial scales. First, at the larger scale, a closed population model describes changes in metapopulation size over time. Second, total metapopulation size is redistributed among subpopulations, using time‐varying proportionality parameters. This two‐step approach ensures that the long‐term growth of every subpopulation is constrained by the overall metapopulation growth rate. It implicitly accounts for the interconnectedness among subpopulations and avoids unrealistic trajectories. Using realistic simulations, we compared the performance of this new model with that of a classical closed population model at predicting subpopulations' trajectories over 30 years. While the classical model predicted future subpopulation sizes with an average bias of 30% and produced predictive errors sometimes >500%, the two‐scale model showed very little bias (<3%) and never produced predictive errors >20%. We also applied both models to a real dataset on European shags (Gulosus aristotelis) breeding along the Atlantic coast of France. Again, the classical model predicted highly unrealistic growths, as large as a 200‐fold increase over 30 years for some subpopulations. The two‐scale model predicted very sensible growths, never larger than a threefold increase over the 30‐year time horizon, which is more in accordance with this species' life history. This two‐scale model provides an effective solution to forecast the local demography of connected subpopulations in the absence of data on dispersal rates. In this context, it is a better alternative than closed population models and a more parsimonious option than full‐dispersal models. Because the only data required are simple counts, this model could be useful to many large‐scale wildlife monitoring programs. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Current and future climate suitability for the hazel dormouse in the UK and the impact on reintroduced populations.
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Cartledge, Emma L., Bellis, Joe, White, Ian, Hurst, Jane L., Stockley, Paula, and Dalrymple, Sarah
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LIFE history theory , *MAMMAL conservation , *SPECIES distribution , *CLIMATE change , *METEOROLOGICAL charts , *GRAPHICAL projection , *POPULATION viability analysis - Abstract
Reintroductions are increasingly being used as a conservation tool to restore species to areas where they once existed. Unfortunately, many reintroduction projects fail to establish viable populations. Climate suitability at release sites is thought to be important in determining reintroduction outcomes, and future climate change is an essential consideration for effective reintroduction planning. Climate change threatens species in a variety of ways, such as by impacting life history traits or causing spatial and temporal distribution mismatches of interdependent species. Hibernating species, such as the hazel dormouse (Muscardinus avellanarius), may be particularly susceptible to changes in climate. For example, milder winters may increase the number of interbout arousals during hibernation, which are energetically costly. Timing of food availability may also be impacted by changing climates, potentially causing mismatches between activity and feeding opportunities. Here, we use species distribution models (SDMs) to map climate suitability for dormice in the UK. We also investigate the impact of climate suitability on a long‐running dormouse reintroduction programme, providing the first such investigation for a reintroduced mammal. We find that higher levels of current climate suitability increase the probability of reintroduction success. We find no effect of climate suitability on adult dormouse counts at reintroduction sites, but dormouse counts decline with time since reintroduction. Future projections predict that climate change may lead to more widespread climate suitability for dormice in the UK, reflecting predicted changes in seasonality, winter temperature and precipitation. Our work demonstrates the importance of understanding changing climate suitability for reintroduction planning, with potential widespread applications of SDMs for conservation projects of low‐dispersing mammals. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Linking PVA models into metamodels to explore impacts of declining sea ice on ice-dependent species in the Arctic: the ringed seal, bearded seal, polar bear complex.
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Lacy, Robert C., Kovacs, Kit M., Lydersen, Christian, and Aars, Jon
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TOP predators ,RINGED seal ,SEA ice ,POLAR bear ,BEAR populations ,POPULATION viability analysis - Abstract
Arctic ecosystems are especially vulnerable to the impacts of climate change because of the limit to possible northward shifts for species dependent on land or continental shelf and because the rate of warming of the region has been 2-4 x the global average in recent decades. The decline in sea ice in the Arctic has both direct and indirect impacts on the species that live in association with ice, breeding on it, traveling over it, feeding on other ice-dependent species or avoiding competition with subarctic species that cannot exploit resources in ice-covered areas. Herein, we present a metamodel of a top-level predator, the polar bear (Ursus maritimus), and two of its key prey species, ringed seals (Pusa hispida) and bearded seals (Erignathus barbatus), which are important in maintaining current polar bear densities and in turn are strongly influenced by bear predation. We used a metamodel that links Population Viability Analyses of the three species in order to examine how the impacts of declining spring land-fast sea ice on the fjords of Svalbard (Norway) and Frans Josef Land (Russia) can cascade through this predator-prey system. As the ice conditions that allow ringed seals to raise pups in snow-covered lairs on the frozen fjords diminish, or even disappear, ringed seal populations using the land-fast sea ice will collapse due to lack of successful recruitment. Consequently, the polar bear population, which relies heavily on hunting ringed seals in the land-fast sea ice to be able to raise their own offspring is also likely to decline. Our models suggest time-lags of decades, with the polar bear population not entering into decline until the lack of recruitment of ringed seals results in the depletion of breeding age ringed seals – starting in the third decade from the start point of the model and dropping below the initial population size only some decades later. Although lags between climate change and impacts on the ice-associated fauna are expected, the sea ice conditions have already changed dramatically in the northern Barents Sea region, including the Svalbard Archipelago, and the collapse of this Arctic species assemblage might already be underway. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Home ranges and movements of an arboreal folivore after wildfire: comparing rehabilitated and non-rehabilitated animals in burnt and unburnt woodlands.
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Lane, Murraya R., Youngentob, Kara N., Clark, Robert G., Skewes, James D., and Marsh, Karen J.
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WILDLIFE conservation ,WILDLIFE rehabilitation ,KOALA ,WILDLIFE management ,ANIMAL populations ,WILDFIRES ,POPULATION viability analysis - Abstract
Background: Wildfires can have complex effects on wildlife populations. Understanding how post-fire conditions affect the movement ecology of threatened species can assist in better conservation and management, including informing the release of rescued and rehabilitated animals. The 2019–2020 megafires in Australia resulted in thousands of animals coming into care due to injury or concerns over habitat degradation. This included hundreds of koalas (Phascolarctos cinereus), for which relatively little was known about how fire affected habitat suitability, or when rehabilitated animals could be returned to burnt areas. Methods: We compared the movements of koalas across three experimental groups–non-rehabilitated koalas in burnt habitat, non-rehabilitated koalas in nearby unburnt habitat, and rehabilitated koalas returned to their rescue location in burnt habitat in New South Wales, Australia. We GPS-tracked 32 koalas for up to nine months and compared, across treatment groups, home ranges, mean nightly distance moved, the farthest distance moved from their release site and total displacement distance. Results: We found no differences in koala movements and home range size between non-rehabilitated koalas in burnt and unburnt habitat. However, rehabilitated koalas moved farther from their release site, had larger displacement distances, and larger home ranges than non-rehabilitated individuals. Regardless of their experimental group, we also found that males moved further than females each night. Additionally, our resource selection analysis showed that, koalas preferred low and moderately burnt habitats over all other fire severity classes. Conclusions: Experimental frameworks that incorporate "treatment" and "control" groups can help isolate disturbance effects on animal movements. Encouragingly, despite catastrophic wildfires, burnt woodlands provided adequate resources for koalas to persist and recover. Furthermore, rehabilitated koalas re-integrated into the burnt landscape despite moving farther from their release sites than non-rehabilitated individuals. Studies like this improve our understanding of the ecological impacts of fire on species and their habitats, and will be instrumental in informing wildlife management and conservation efforts as wildfires increase in frequency and severity worldwide in response to climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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19. Waterbirds of Sardinia (Italy): How Space and Time Shape a Threatened Metacommunity During the Critical Summer Period.
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Ferrarini, Alessandro, Gustin, Marco, and Celada, Claudio
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MIGRATION flyways ,WATER management ,COASTAL wetlands ,NUMBERS of species ,BIRD conservation ,POPULATION viability analysis - Abstract
The wetlands of Sardinia (Italy) supply food and shelter for many waterbird species that migrate along the central–eastern Mediterranean bird flyway. Despite many different policies and laws (the Birds and Habitats Directives, the European Water Framework Directive, and the Ramsar Convention), the Sardinian wetlands are seriously threatened by human activities and climate change, which in turn menace the associated avifauna. In this study, we (a) inventoried (four sampling dates) the avian metacommunity of the largest coastal wetlands in Sardinia during the crucial period of the year for the avifauna (August–September), (b) explored the spatiotemporal dynamics in bird species assemblage, and (c) used results to refine planning for bird habitat management and bird diversity conservation. We recorded 60 bird species, of which 54 were migratory and 21 belonged to Annex I of the Birds Directive. During August–September, (a) α, β, and γ avian diversity showed no significant temporal trends, (b) the contributions of space (wetlands) and time (dates of sampling) in determining the presence/absence of the waterbird species were comparable, (c) wetlands formed three statistically significant clusters with regard to the species richness, (d) a significant increase in the number of the species belonging to the "mixed" migration guild, and "divers from the surface" foraging guild, occurred, (e) there was a statistically significant chronological succession of the occurrence of waterbird species, (f) twenty-five species made use of the Sardinian wetlands all summer long, while ten further species were present in three sampling dates out of four, (g) the spatial distributions of the waterbird species in the Sardinian wetlands were significantly different between the sampling dates, (h) the Little Egret, the Grey Heron, and the Greater Flamingo were primarily responsible for the observed difference in the spatial distributions of species between the sampling dates, (i) Is Brebeis, Pilo, and S. Giovanni were the wetlands that changed their species composition the most during the studied period, (j) twenty-two waterbird species resulted at high priority for conservation, and thirteen species at medium priority. Based on these results, we have proposed new strategies for the conservation of the waterbird species of the Sardinian wetlands during the post-breeding migration period. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Fire return intervals and recruitment affect population growth rate of canopy trees in tall open forest in humid savanna.
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Werner, Patricia A. and Peacock, Stephanie J.
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LIFE history theory ,POPULATION viability analysis ,FIRE management ,RECRUITMENT (Population biology) ,HAWTHORNS - Abstract
Savannas are the major biome in tropical regions of the globe, defined as sparsely wooded regions with a continuous herbaceous layer of mainly C4 grasses where rainfall is distinctly seasonal. Fire is a common feature of most savannas. The largest protected areas of savannas are found in sparsely populated monsoonal northcentral Australia with strong annual wet and dry seasons. The most common vegetation type is relatively intact, tall (<15 m), open forests where Eucalyptus canopy trees form the basic structure. Over the past half century, traditional indigenous fire regimes were largely replaced by contemporary fires where individual trees may experience fire as often as 3 out of 5 years. The potential for long‐term persistence of the canopy tree populations is an open question. A stage‐based population model of the canopy trees was previously developed to address this question, drawing on data from three decades of experimental field studies wherein the survival, growth, and reproduction of individual marked trees were recorded under different seasonal fires and understory types to produce transition matrices among eight life history stages, and used to calculate population growth rates (λ). Here, we apply that model to determine how λ varies across a range of fire return intervals from 1 to 12 years for both early and late dry season fires, in two different understory types. We also explore the sensitivity of λ to two key life history parameters: recruitment and seedling survival. Minimum fire return intervals of 2–5 years were generally required for λ ≥1 that would allow populations to persist; these were shorter with stochastic year‐to‐year timing of fires and with higher recruitment rates. Uniquely, under certain conditions, there was also a maximum fire return interval above which λ <1, creating a "window" of fire return intervals that allowed canopy tree populations to persist. Mechanisms underpinning results as well as implications for savanna structure, alternate states, cyclical dynamics, future research, and management by fire are discussed. [ABSTRACT FROM AUTHOR]
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- 2024
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21. A systematic review protocol for quantifying bycatch of critically endangered leatherback sea turtles within the Pacific Ocean basin.
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Ortega, Anna A., Mitchell, Nicola J., Marn, Nina, and Shillinger, George L.
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POPULATION viability analysis ,BYCATCHES ,LEATHERBACK turtle ,TURTLE populations ,SMALL-scale fisheries ,BIBLIOGRAPHIC databases - Abstract
Background: The Pacific Ocean supports two leatherback sea turtle populations, each of which is Critically Endangered primarily as a result of ongoing incidental bycatch within small-scale and industrial fisheries. Conservation planning has included population viability analysis (PVA), which depends on accurate data on mortality and morbidity (sublethal effects) rates to yield realistic results that can inform management decision-making. Existing leatherback PVAs are based on best available data, however, estimates of mortality and morbidity rates are heavily influenced by estimates of bycatch. These, in turn, are based on unknown levels of observer coverage in many fisheries, estimated to be less than 1% coverage in some artisanal and industrial fleets. Leatherback population recovery depends on bycatch reduction. It is vital to understand the source, scope, and scale of leatherback bycatch wherever and whenever leatherbacks occur. Here, we outline a protocol for a systematic review to aggregate existing estimates of leatherback bycatch within the Pacific Ocean, on a population- and basin-level. These results will generate the first comprehensive estimate of leatherback turtle bycatch for any ocean basin and will be incorporated into future conservation planning for Pacific Ocean populations. Methods: A Boolean search string will be input into several bibliographic databases to yield articles and grey literature (governmental, business, and industry information not controlled by commercial publishing) related to the research question. Additional grey literature searches, snowball sampling and expert elicitation will be used to create as robust and comprehensive a pool of literature and/or databases as possible. Retrieved articles will be reviewed for eligibility using the SPIDER search strategy tool (Sample— Phenomenon of Interest—Design—Evaluation —Research type; 7). Articles which meet the criteria will be included in the systematic review, and their data will be collated into comprehensive estimates of leatherback sea turtle bycatch within the Pacific Ocean, one for each population. These data will be further teased apart by fishery size, fishing gear type, fishing nation, fishery region, and fishery target species, to target management more directly. This information will be published and provided directly to stakeholders for use in conservation management. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Satellite telemetry reveals complex mixed movement strategies in ibis and spoonbills of Australia: implications for water and wetland management.
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McGinness, Heather M., Lloyd-Jones, Luke R., Robinson, Freya, Langston, Art, O'Neill, Louis G., Rapley, Shoshana, Jackson, Micha V., Hodgson, Jessica, Piper, Melissa, Davies, Micah, Martin, John M., Kingsford, Richard, Brandis, Kate, Doerr, Veronica, and Mac Nally, Ralph
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SATELLITE telemetry ,WETLAND management ,WETLAND conservation ,LIFE cycles (Biology) ,ARTIFICIAL satellite tracking ,POPULATION viability analysis - Abstract
Waterbird population and species diversity maintenance are important outcomes of wetland conservation management, but knowledge gaps regarding waterbird movements affect our ability to understand and predict waterbird responses to management at appropriate scales. Movement tracking using satellite telemetry is now allowing us to fill these knowledge gaps for highly mobile waterbirds at continental scales, including in remote areas for which data have been historically difficult to acquire. We used GPS satellite telemetry to track the movements of 122 individuals of three species of ibis and spoonbills (Threskiornithidae) in Australia from 2016 to 2023. We analysed movement distances, residency periods and areas, and foraging-site fidelity. From this we derived implications for water and wetland management for waterbird conservation. This is the first multi-year movement tracking data for ibis and spoonbills in Australia, with some individuals tracked continuously for more than five years including from natal site to first breeding attempt. Tracking revealed both inter- and intra-specific variability in movement strategies, including residency, nomadism, and migration, with individuals switching between these behaviours. During periods of residency, areas used and distances travelled to forage were highly variable and differed significantly between species. Sixty-five percent of identified residency areas were not associated with wetlands formally listed nationally or internationally as important. Tracking the movements of waterbirds provides context for coordinated allocation of management resources, such as provision of environmental water at appropriate places and times for maximum conservation benefit. This study highlights the geographic scales over which these birds function and shows how variable waterbird movements are. This illustrates the need to consider the full life cycle of these birds when making management decisions and evaluating management impacts. Increased knowledge of the spatio-temporal interactions of waterbirds with their resource needs over complete life cycles will continue to be essential for informing management aimed at increasing waterbird numbers and maintaining long-term diversity. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Modelling decisions and density dependence in monarch butterflies: A comment on Meehan and Crossley (2023).
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Crone, Elizabeth E., Murphy, Atticus W., and Schultz, Cheryl B.
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- *
POPULATION viability analysis , *WILDLIFE conservation , *ENDANGERED species , *INSECT conservation , *TIME series analysis , *MONARCH butterfly - Abstract
Decisions about which processes to include in a population model can have substantial impact on estimates of population trends and extinction risk. This is particularly important for species of conservation concern, whose conservation status is decided in part on the basis of these models.In their recent paper, Meehan and Crossley (2023) Insect Conservation and Diversity, 16, 566–573 revisit a time series of overwintering monarch butterfly abundances, which previous assessments had characterised as rapidly declining and at risk of extinction. The authors, in contrast, reported no evidence for declines in the past 10 years and characterised extinction risk as low.A primary reason for the difference between these conclusions was that Meehan and Crossley used a more complex model that included a parameter for density dependence. While negative density dependence may play a role in monarch population regulation, there are a variety of unresolved issues with how and if density dependence should be included in models of monarch populations, including widely known issues with separating observation error from density dependence in noisy time series and taxon‐specific issues with fitting models to data surveyed every fourth generation and pooled at continental scales.These issues make the conclusions of Meehan and Crossley about monarch population viability much less robust than implied in their article. They do not provide convincing evidence that density dependence reduces extinction risk in monarch butterflies. Our commentary supports their general conclusion that population viability projections depend on model assumptions, but the ways in which monarch butterfly populations are regulated remains an open question. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Quantifying public support for culling crown‐of‐thorns starfish (Acanthaster spp.) on the Great Barrier Reef.
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Lockie, Stewart, Bartelet, Henry A., Ritchie, Brent W., Sie, Lintje, and Paxton, Gillian
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- *
MARINE ecosystem management , *MARINE resources conservation , *WILDLIFE management , *WILDLIFE conservation , *CORAL reefs & islands , *POPULATION viability analysis - Abstract
Population surges of crown‐of‐thorns starfish (COTS) (Acanthaster spp.) are a leading cause of coral cover loss on Australia's Great Barrier Reef (GBR). While COTS culling has been undertaken since 2012 little is known about how the public perceive COTS culling or how perceptions vary among social groups. Drawing on survey data collected in 2018 and 2022 we test the relative influence of demographic variables, social and institutional variables, and beliefs concerning the risks and benefits of culling, on public acceptance for the culling of COTS on the GBR. In contrast with previous research suggesting a polarization of views, we found limited opposition to culling (12% in 2018 and 8% in 2022). Remaining respondents, however, were almost equally divided between those who agreed or strongly agreed with culling and those who were neutral or only slightly in agreement. The strongest predictors of support, in terms of standardized mean odds ratios, were the perceived social, environmental, and ethical responsibility of culling (1.57), the manageability of culling risks (1.46), the personal importance of the GBR to the respondent (1.33), trust in science to deliver solutions (1.30), confidence in management of the GBR (1.26), and how much of a threat respondents believed COTS posed to the Reef (1.25). These findings suggest public communications about COTS culling might usefully focus on how scientific understanding, ongoing research, ecosystem monitoring, and partnerships with Reef Traditional Owners and stakeholders guide operations. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Development of an assay for the detection of the federally threatened Florida eastern indigo snake (Drymarchon couperi) using soil eDNA.
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Santamaria, Carlos A., Galbraith, Emily, and Gainsbury, Alison M.
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- *
WILDLIFE conservation , *ENDANGERED species , *CYTOCHROME b , *HABITAT destruction , *DNA , *POPULATION viability analysis , *ANIMAL burrowing - Abstract
Accurate information on species range contraction is the cornerstone of effective biodiversity conservation. The eastern indigo snake (Drymarchon couperi) is an apex predator in Florida and, similar to many species native to Florida, is threatened by widespread habitat destruction. Environmental deoxyribonucleic acid (eDNA) monitoring of this elusive snake would provide a non‐invasive approach to improve our knowledge of the species' range and distribution. We designed and tested an eDNA assay that can detect the presence of D. couperi from soil samples from their natural scrub habitat in Florida. We validated our assay in silico, in vitro, and in situ. Furthermore, we investigated the influence of temperature and humidity on the degradation rate of eDNA over time. We successfully amplified the cytochrome b gene for D. couperi at concentrations as low as 3 × 10−3 ng/μL and successfully detected the presence of D. couperi in 2 of 30 in situ field soil samples. The degradation experiment resulted in detectable DNA for 10 days. Interestingly, temperature and humidity had no effect on the degradation rate of eDNA in our experimental conditions. This study provides support for soil eDNA applications to detect the presence of a federally threatened species in their natural environment bolstering our ability to monitor the conservation and management of imperiled species. Environmental DNA provides an additional conservation tool to quickly and effectively monitor species range shifts driven by multiple anthropogenic stressors to promote the persistence of imperiled species. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Die ,komplementäre Ehe' als ironische Erzählfigur: Wilhelm Raabes Auseinandersetzung mit dem bürgerlichen Harmoniegedanken.
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Ullmann, Verena
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SOCIAL norms ,MASCULINE identity ,IDENTITY crises (Psychology) ,NINETEENTH century ,CONCORD ,POPULATION viability analysis ,MARRIED people - Abstract
Copyright of Jahrbuch der Raabe-Gesellschaft is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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27. Multispecies language landscapes: (Re)making beachscapes with monk seals in Hawai'i.
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Lamb, Gavin
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PUBLIC spaces ,ABSOLUTE sea level change ,SEA lions ,ENDANGERED species ,LINGUISTIC landscapes ,POPULATION viability analysis - Abstract
The Hawaiian monk seal is the most endangered of all pinnipeds (walruses, sea lions, and seals). The threat of extinction has loomed large for these seals, especially as sea-level rise threatens to inundate their primary habitat, but an alliance of conservation actors, from federal agencies to non-profit volunteer groups, are working to bring this species back from the brink in Hawai'i. Today, the monk seal population is finally beginning to recover, but as monk seals make a comeback and reclaim busy beaches, new and unpredictable human relationships with monk seals are taking shape in an uncertain time of climate change. Drawing on data from my ethnographic research of the monk seal-human contact zone in Hawai'i, in this article, I explore possibilities for a multispecies approach to linguistic and semiotic Landscape research that seeks to 'multiply' our understanding of social life and meaning-making in public space as a rich, multispecies entanglement. Ka Moʻolelo i Hoʻopōkole ʻia: ʻO ka ʻīlio holoikauaua ka holoholona e ʻaneʻane loa nei i ka nalowale loa ma waena o ia lāhui holoholona (e laʻa ka palaʻo, ka liona kai, a me ka sila hoʻi). He hoʻoweliweli nui ʻia ia holoholona, he oki loa hoʻi ma muli o ka piʻi ʻana mai o ke kai me ka hālana ʻia o ko lākou wahi noho, akā naʻe, aia nō kekahi poʻe no ke aupuni pekelala a he mau lima kōkua hoʻomanawaleʻa hoʻi, ke ʻimi like akula i ka mea e pono ai ia lāhui holoholona ma Hawaiʻi. I kēia mau lā, aia nō ia lāhui holoholona ke kōnea nei me ka ulu hou mai o kona heluna nui, i ka wā naʻe e māhuahua aʻe nei lākou me ka noho ma nā kahakai paʻapū iā kānaka, he mahaʻoi paha ke ʻano o kānaka e hana aku ai i ia poʻe holoholona, a he kānalua kahi a pili ai me lākou i loko o kēia wā o ka loli ʻana o ke aniau. Ma ka hōʻike ʻana i ka ʻike i loaʻa mai ma kaʻu ʻimi noiʻi ʻana ma nā wahi e launa pū ai kānaka me ia poʻe holoholona i Hawaiʻi, ma kēia ʻatikala, e ʻimi aku nō au i mau wahi e ʻimi noiʻi ai i ka waihona ʻāina ma ke ʻano kālai ʻōlelo a kālai hōʻailona hoʻi, i mea e 'māhuahua' aʻe ai ko kākou hoʻomaopopo ʻana i ka nohona pilikanaka a me ke kūkulu manaʻo ʻana, me he ʻupena hihi lā e hihia ai nā ʻano lāhui like ʻole. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Long live the cat: Ocelot population viability in a planned reintroduced population in Texas, USA.
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Martinez, Lindsay A., Lombardi, Jason V., Parker, Israel D., East, Forrest, Campbell, Tyler A., and Lopez, Roel R.
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POPULATION viability analysis ,ENDANGERED species ,HABITAT conservation ,GENETIC variation ,INBREEDING ,WILDLIFE reintroduction - Abstract
Reintroductions are often needed to recover carnivore populations and restore ecological processes. Felids are common subjects of reintroduction efforts, but published population models informing felid reintroduction plans are uncommon, and poor planning has sometimes caused issues in felid reintroduction programs. In the United States, ocelots (Leopardus pardalis pardalis) are classified as endangered, and recovery requires population expansion into historic habitat. A multi‐organization effort is underway to establish a new ocelot population in Texas by releasing ocelots into an area of 478 km2 of suitable habitat in ocelots' historic but now unoccupied range. In this study, we used population viability analyses to compare different ocelot reintroduction strategies for the identified reintroduction area. Based on a potential ocelot breeding program's limitations, we modeled reintroduction using a founding population of no more than six ocelots and no more than four ocelots released per year for no more than 15 subsequent years. Within these limitations, we assessed projected population abundances and extinction risks after 30 years for 20 different reintroduction strategies. We found that long‐term releases are necessary to establish a viable population; under conservative model assumptions, releasing six ocelots in the initial year and then releasing four individuals annually for an additional 10–15 years is necessary for attaining a projected population greater than 36.62 ocelots (baseline) with <6% extinction risk. We also found that ocelot population abundance is about equally sensitive to post‐release mortality and inbreeding depression. This highlights the importance of not only supporting reintroduced ocelots' survival but also managing for high genetic diversity in the reintroduction program. Further, we found that realistic but more liberal assumptions on the carrying capacity of the reintroduction area and the age of first reproduction for ocelots increase projected population abundances (53.95 individuals and 61.26 individuals, respectively), and thus reintroduction success. The model's sensitivity to carrying capacity suggests that long‐term habitat protection and expansion are among the most important management actions to support ocelot reintroduction. Our study establishes the first population viability model for an ocelot reintroduction plan anywhere across the species' wide geographic range, and it reinforces several key considerations for wildlife reintroduction efforts worldwide. [ABSTRACT FROM AUTHOR]
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- 2024
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29. Ecological and biological features of some rare and endemic plant species of south-east Kazakhstan.
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Sadyrova, G. A., Shimshikov, B. E., Tynybekov, B. M., Nurmakhanova, A. S., Orazbekova, K. S., Tastybay, M. B., Imanaliyeva, M. T., and Bekbossyn, N. A.
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- *
ENDEMIC plants , *ENDEMIC species , *ENDANGERED species , *RARE plants , *PLANT species , *PLANT identification , *POPULATION viability analysis - Abstract
The article presents the results of ecological and biological analysis of species composition of five rare and endangered endemic plant species of southeastern Kazakhstan listed in the Red Book of the Republic of Kazakhstan. The importance of this research topic is determined by the need for a comprehensive and in-depth understanding of the ecological and biological characteristics of rare plant species growing in the southeast of Kazakhstan. The studies were conducted in the southeast of Kazakhstan (Zailiysky Alatau, Ketpen), where the objects of the study were representatives of rare and endangered endemic plant species: Astragalus rubtzovii Boriss, Taraxacum kok-saghyz L.E. Rodin., Schmalhausenia nidulans (Regel) Petr. Betula Jarmolenkoana Golosk., Rheum wittrockii Lundstr., from natural populations. The study of the state of the coenopopulation of rare and endemic plant species was carried out by route and semi-stationary methods. The novelty of the work is that for the first time the most complete ecological and biological characteristics of rare and endangered endemic plant species of the southeast of Kazakhstan are given, their biological features and habitat characteristics are studied. In the study area, 5 identified rare and endangered endemic plant species are represented by 2 types of life forms, where the predominant group among rare and endemic species is hemiocryptophytes (perennial plants) and one species is represented by a phanerophyte - a woody plant (Betula jarmolenkoana). [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Making Noah's Ark Work for Fishing Cat Conservation: A Blueprint for Connecting Populations across an Interactive Wild Ex Situ Spectrum.
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Adhya, Tiasa, Singh, Simran, Gottumukkala, Himaja Varma, Banerjee, Aditya, Chongder, Ishita, Maity, Sulata, and Reddy, P. Anuradha
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- *
POPULATION viability analysis , *CAT breeds , *FELIDAE , *FISH conservation , *ANIMAL welfare , *HYBRID zones - Abstract
Simple Summary: This study presents an integrated conservation framework for the globally threatened fishing cat, synthesizing both ex situ management and in situ strategies. The strategy aligns with the One Plan Approach, which views captive populations as part of a broader metapopulation network, and the Opportunities to Thrive framework, which emphasizes animal welfare in captivity. This study analyzed the genetic diversity of a recently initiated fishing cat captive breeding population by the West Bengal Zoo Authority, India, and conducted a population viability analysis. The results suggest that the current genetic diversity (56%) and population carrying capacity (30 individuals) can be sustained for over 100 years through a strategy of supplementation and harvesting. Introducing two adult males and females annually will allow for sustainable harvesting to supplement wild populations. Additionally, this study identified 21 potential reintroduction zones in the Sundarbans and Terai regions of West Bengal, using environmental criteria that favor fishing cat occurrence. This work offers a comprehensive blueprint for applying the One Plan Approach to ensure the long-term survival of the fishing cat. The One Plan Approach advocates for a hybrid species management framework, wherein captive-bred populations are considered metapopulations nested within a broader network of zoos and wild populations Additionally, the Opportunities to Thrive framework aims to enhance animal welfare by addressing the physiological, psychological, and emotional needs of captive individuals, thereby improving conservation outcomes. Here, we present an integrated framework for the conservation of a globally threatened wetland wild cat species, the fishing cat, by synthesizing optimal ex situ management practices and in situ conservation strategies. Further, we examined the genetic constitution of the founder population in a fishing cat captive breeding program that was recently initiated by the West Bengal Zoo Authority, India and conducted a population viability analysis to suggest how best to maintain the genetic diversity of the population. We found that the present genetic diversity of 56% and maximum carrying capacity of the captive population (30 individuals) can be maintained for more than 100 years with a combination of supplementation and harvesting. Keeping stochastic events in mind, the introduction of two adult males and females to the existing population each year will seamlessly allow the harvesting of two adult males and two adult females every alternate year to supplement wild populations. Further, we adopted the proposed integrated framework to delineate recommendations for the supplementation of wild populations in West Bengal. We used environmental criteria known to influence fishing cat occurrence to identify 21 potential reintroduction zones in the Sundarbans landscape and Terai region in northern West Bengal with habitable areas for the fishing cat that are larger than the maximum known species' home range. Our study is timely and insightful because it provides a holistic blueprint for implementing the One Plan Approach in safeguarding a threatened species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Incorporating density‐dependent regulation into impact assessments for seabirds.
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Merrall, Eve, Green, Jonathan A., Robinson, Leonie A., Butler, Adam, Wood, Matt J., Newell, Mark A., Black, Julie, Daunt, Francis, and Horswill, Catharine
- Subjects
- *
POPULATION viability analysis , *ENVIRONMENTAL impact analysis , *POPULATION dynamics , *PRECAUTIONARY principle , *WEIBULL distribution - Abstract
Many industries are required to perform population viability analysis (PVA) during the consenting process for new developments to establish potential impacts on protected populations. However, these assessments rarely account for density‐dependent regulation of demographic rates. Excluding density‐dependent regulation from PVA‐based impact assessments is often assumed to provide a maximum estimate of impact and therefore offer a precautionary approach to assessment. However, there is also concern that this practice may unnecessarily impede the development of important industries, such as offshore renewable energy.In this study, we assess density‐dependent regulation of breeding success in 31 populations of seabird. We then quantify the strength and form of this regulation using eight different formulations. Finally, we use PVA to examine how each formulation influences the recreation of observed dynamics (i.e. model validation), as well as the predicted absolute and relative population response to an extrinsic threat (i.e. model projection).We found evidence of both negative (n = 3) and positive (n = 5) regulation of seabird breeding success. In populations exhibiting negative regulation, excluding density‐dependent regulation from PVA‐based impact assessment allowed uncontrolled population growth, such that model outcomes became biologically implausible. By contrast, in populations exhibiting positive regulation, excluding density‐dependent regulation provided an appropriate reconstruction of observed dynamics, but population decline was underestimated in some populations. We find that multiple formulations of density dependence perform comparably at the detection, validation and projection stages of analysis. However, we tentatively recommend using a log‐linear or Weibull distribution to describe density‐dependent regulation of seabird breeding success in impact assessments to balance accuracy with caution. Finally, we show that relative PVA metrics of impact assessment cannot necessarily be used to overcome PVA misspecification by assuming density independence in positively regulated populations.Synthesis and applications: We suggest that a density‐dependent approach when performing PVA‐based assessments for seabird populations will prevent biologically unrealistic, unconstrained population growth and therefore ensure meaningful PVA metrics in populations experiencing negative regulation. It will also maintain a precautionary approach for populations experiencing positive regulation, crucial when estimating impacts for these more vulnerable populations. These conclusions have immediate international application within the consenting processes for marine industries. [ABSTRACT FROM AUTHOR]
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- 2024
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- View/download PDF
32. EMERGENCE OF FOREST ENVIRONMENTAL KUZNETS CURVE IN AFRICA: SOME NEW EVIDENCES.
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Shobande, Olatunji A. and Ogbeifun, Lawrence
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- *
KUZNETS curve , *DEFORESTATION , *FOREST management , *RESTORATION ecology , *ENVIRONMENTAL quality , *POPULATION viability analysis , *ILLEGAL logging - Abstract
The African continent, renowned for its diverse landscapes and abundant biodiversity, grapples with a critical environmental challenge - deforestation. The swift depletion of forests, serving as the primary habitat for 80% of the world's terrestrial animals and plants, poses a severe threat in Africa. Human activities, including logging, agricultural expansion, and urbanization, have jeopardized numerous ecosystems, exacerbating the overarching global climate crisis. Beyond serving as mere collections of trees, forests are intricate ecosystems supporting a staggering diversity of flora and fauna. The repercussions of forest loss in Africa are profound, resulting in a significant decline in biodiversity. Numerous species, some exclusive to these ecosystems and found nowhere else on the planet, now teeter on the brink of extinction. The predicament of deforestation in Africa is intimately intertwined with the broader global challenge of climate change. Urgency is paramount in addressing this crisis, as the loss of forests impacts not only local ecosystems but also exacerbates the overarching climate emergency. Reforestation emerges as a pivotal solution, offering an opportunity to reverse the damage inflicted on these vital ecosystems. This study examines whether forest natural resources can explain the environmental Kuznets curve hypothesis in African countries. The empirical strategy is based on the second-generation cointegration approach, cross-sectional dependency autoregressive distributed lag (CS-ARDL) and Augmented Mean Group (AMG) estimator. The findings show a potential long-run relationship between the forest rent and the environment. Further analysis highlights the importance of effective management of natural forest resources for improving environmental quality in Africa. We recommend that policymakers prioritize the restoration of ecosystems that have suffered carbon depletion due to human activities. Restoration efforts should strategically aim to enhance carbon sequestration capacity and rebuild biodiversity. Additionally, the establishment of robust monitoring and reporting systems is imperative to track current carbon emissions from forests. This entails regular assessments of forest carbon stocks, landuse changes, and the effectiveness of ongoing conservation and restoration initiatives. [ABSTRACT FROM AUTHOR]
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- 2024
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- View/download PDF
33. A landscape conservation perspective of state Species of Greatest Conservation Need.
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Hamilton, Healy, Rapacciuolo, Giovanni, Kanter, John, Jones‐Farrand, D. Todd, and Young, Bruce E.
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- *
WILDLIFE conservation , *ENDANGERED species , *REGIONAL cooperation , *SHRIMPS , *FRESH water , *POPULATION viability analysis - Abstract
State Wildlife Action Plans (SWAPs), including lists of Species of Greatest Conservation Need (SGCN), outline state strategies for protecting species and habitats in the United States. In developing the current, second revision SWAPs, states are increasingly pursuing coordinated landscape conservation approaches. Analyzing SGCN lists in the first revision SWAPs, we found evidence that they already support multistate conservation. Most states address a common set of vertebrate and invertebrate groups, include most of the imperiled species from these groups, do not prioritize endemics over non‐endemics, and often include most imperiled species that are shared with neighboring states. Also, a regional SGCN coordination effort was successful. Although 65% of animals on each SGCN list were assessed as at elevated risk of extirpation by state authorities, only 43% of the combined national list were at elevated risk of global extinction. Over 40% of the combined animal SGCNs are considered globally apparently secure. Plants, snails, freshwater shrimps, and freshwater insects were poorly represented in SGCN lists. For the current SWAP revisions, we recommend improving foundational data on taxonomy, range‐wide distribution, and conservation status; expanded taxonomic coverage in SGCN lists; supporting existing and establishing new interstate initiatives; and diversifying funding mechanisms that target regional cooperation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Scale‐dependent population drivers inform avian management in a declining saline lake ecosystem.
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Van Tatenhove, Aimee M., Neill, John, Norvell, Russell E., Stuber, Erica F., and Rushing, Clark S.
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SALT lakes ,POPULATION viability analysis ,COLONIES (Biology) ,WILDLIFE management ,POPULATION forecasting ,WETLAND management - Abstract
Shrinking saline lakes provide irreplaceable habitat for waterbird species globally. Disentangling the effects of wetland habitat loss from other drivers of waterbird population dynamics is critical for protecting these species in the face of unprecedented changes to saline lake ecosystems, ideally through decision‐making frameworks that identify effective management options and their potential outcomes. Here, we develop a framework to assess the effects of hypothesized population drivers and identify potential future outcomes of plausible management scenarios on a saline lake‐reliant waterbird species. We use 36 years of monitoring data to quantify the effects of environmental conditions on the population size of a regionally important breeding colony of American white pelicans (Pelecanus erythrorhynchos) at Great Salt Lake, Utah, US, then forecast colony abundance under various management scenarios. We found that low lake levels, which allow terrestrial predators access to the colony, are probable drivers of recent colony declines. Without local management efforts, we predicted colony abundance could likely decline approximately 37.3% by 2040, although recent colony observations suggest population declines may be more extreme than predicted. Results from our population projection scenarios suggested that proactive approaches to preventing predator colony access and reversing saline lake declines are crucial for the persistence of the Great Salt Lake pelican colony. Increasing wetland habitat and preventing predator access to the colony together provided the most effective protection, increasing abundance 145.4% above projections where no management actions are taken, according to our population projection scenarios. Given the importance of water levels to the persistence of island‐nesting colonial species, proactive approaches to reversing saline lake declines could likely benefit pelicans as well as other avian species reliant on these unique ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Population viability analysis predicts long‐term impacts of commercial Sooty Tern egg harvesting to a large breeding colony on a small oceanic island.
- Author
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Inch, Thalissa, Nicoll, Malcolm A.C., Feare, Chris J., and Horswill, Catharine
- Subjects
COLONIES (Biology) ,SPECIES diversity ,DEMOGRAPHIC change ,TERNS ,EGGS - Abstract
The over‐exploitation of wild birds and the products derived from them can be a key threat driving changes in bird species richness and abundance. However, inadequate information on harvest levels combined with irregular population monitoring often means that the role of harvesting in population decline is difficult to quantify. Historically, the pan‐tropical Sooty Tern Onychoprion fuscatus has been subjected to extensive egg harvesting, yet the role of sustained harvesting in population change and future population viability remains unclear. In this study, we used published and new estimates of key demographic rates for a large, harvested Sooty Tern population in Seychelles, western Indian Ocean, to run a series of population viability analyses. We retrospectively assess the impact of historical levels of egg harvesting, and also predict how this population may respond under different future harvesting regimes, assuming no additional environmental change. We provide evidence that egg harvesting has played a substantial role in driving the population decline of Sooty Terns to date and demonstrate that continued harvesting will probably lead to further, possibly dramatic, declines in population size. These results indicate that recent levels of egg harvesting in Seychelles are not sustainable. We also show that the life‐history strategy of Sooty Terns, including a delayed age of first breeding, means the current 2‐year local moratorium on egg harvesting is unlikely to generate an observable population‐level response in Seychelles. Instead, we recommend that the current moratorium is extended at least beyond the age of first breeding (i.e. 5 years) to support appropriate evaluation. We additionally show that harvesting Sooty Tern eggs at much lower levels, i.e. 10% of the population size, is unlikely to reverse population decline. Therefore, long‐term egg harvesting strategies require careful evaluation to maintain a balance between the social, commercial, cultural and biodiversity significance of Sooty Terns in Seychelles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Harvest sustainability assessments need rethinking under climate change: A ringed seal case study from Svalbard, Norway.
- Author
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Nater, Chloé R., Lydersen, Christian, Andersen, Magnus, and Kovacs, Kit M.
- Subjects
POPULATION viability analysis ,MARINE mammal populations ,DEMOGRAPHIC surveys ,RINGED seal ,SEA ice - Abstract
Throughout the Arctic, ice‐affiliated marine mammals constitute local subsistence resources but detrimental effects of declines in their sea ice habitats create a need for harvest sustainability assessments in light of climate change. At the same time, empirical data required for thorough population analysis of these species are often sparse at best, as illustrated by the focal species in this study, ringed seals in Svalbard: the last population survey took place two decades ago (2002–2003), demographic data are limited to age, sex, and reproductive status of a small subset of shot individuals, and harvest reporting is patchy and incomplete. Data sparsity is one of the main reasons why potential biological removal (PBR) became a commonly used tool for assessing sustainability of marine mammal harvests. Herein, we calculated PBR for Svalbard ringed seals using both recommended default parameters and population‐specific parameters obtained from an integrated population model (IPM). PBR estimates were highly uncertain, suggesting the number of sustainably harvestable individuals could lie anywhere between 0 and 91, with a substantial chance of any harvest being unsustainable under current environmental conditions and trends. Subsequent population viability analyses (PVAs) further confirmed that the current harvest was likely unsustainable, even in a scenario in which sea ice conditions would not deteriorate (and therefore lower pup survival) further. However, uncertainty in population projections was high, and forecasts thus not ideal for formulating management advice. Better forecasts will require more frequent population surveys and obtaining more knowledge regarding the links between vital rates and environmental conditions, both of which may be facilitated by the adoption of novel technology (e.g., drone monitoring, genetic studies). The modeling framework created in this study can be readily updated with new data as they become available, and can serve as a tool for adaptive management of this and other marine mammal populations. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Evaluating the effects of nest management on a recovering raptor using integrated population modeling.
- Author
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Cappello, Caroline D., Jacobson, Kenneth V., Driscoll, James T., McCarty, Kyle M., and Bauder, Javan M.
- Subjects
POPULATION viability analysis ,BALD eagle ,POPULATION dynamics ,NUMBERS of species ,BIRDS of prey - Abstract
Evaluating population responses to management is a crucial component of successful conservation programs. Models predicting population growth under different management scenarios can provide key insights into the efficacy of specific management actions both in reversing population decline and in maintaining recovered populations. Bald eagle (Haliaeetus leucocephalus) conservation in the United States has seen many successes over the last 50 years, yet the extent to which the bald eagle population has recovered in Arizona, an important population within the Southwest region, remains an area of debate. Estimates of the species' population trend and an evaluation of ongoing nest‐level management practices are needed to inform management decisions. We developed a Bayesian integrated population model (IPM) and population viability analysis (PVA) using a 36‐year dataset to assess Arizona bald eagle population dynamics and their underlying demographic rates under current and possible future management practices. We estimated that the population grew from 77 females in 1993 to 180 females in 2022, an average yearly increase of 3%. Breeding sites that had trained personnel (i.e., nestwatchers) stationed at active nests to mitigate human disturbance had a 28% higher reproductive output than nests without this protection. Uncertainty around population trends was high, but scenarios that continued the nestwatcher program were less likely to predict abundance declines than scenarios without nestwatchers. Here, the IPM‐PVA framework provides a useful tool both for estimating the effectiveness of past management actions and for exploring the management needs of a delisted population, highlighting that continued management action may be necessary to maintain population viability even after meeting certain recovery criteria. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Conservation biology of three threatened Limonium species endemic to Zakynthos Island (Ionian Islands, Greece)
- Author
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Anna-Thalassini Valli, Charikleia Papaioannou, Eleni Liveri, Vasileios Papasotiropoulos, and Panayiotis Trigas
- Subjects
IUCN criteria ,Limonium ,littoral species ,Mediterranean plants ,microsatellites ,monitoring ,population viability analysis ,Zakynthos Island ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Knowledge of the life history traits, reproductive biology and demography of rare species is fundamental for their conservation, yet plant population monitoring is uncommon. The restricted ranges of the Limonium species endemic to the Mediterranean area, combined with the vulnerability of their specialized littoral habitats, indicate the need for appropriate conservation measures. We evaluate the conservation status and estimate the future extinction risk of three Limonium species endemic to Zakynthos Island in the Ionian Islands, Greece (Limonium korakonisicum, Limonium phitosianum and Limonium zacynthium) using 5 years of monitoring data. We compile information on their geographical distribution, population dynamics, reproductive biology and genetic diversity. Population sizes and survival rates of seedlings exhibited marked annual fluctuations, although fecundity and relative reproductive success remained high throughout the monitoring period. We observed a dominance of mature individuals in all three species, indicating their increased tolerance to salinity. Three subpopulations each of L. phitosianum and L. zacynthium were genotyped using five microsatellite loci. The observed number of alleles and the low gene flow value potentially indicate reduced genetic diversity, inbreeding, and limited gene flow within and among subpopulations of both species. Based on the IUCN categories and criteria, we assess L. korakonisicum as Critically Endangered, L. phitosianum as Near Threatened and L. zacynthium as Endangered. Population viability analyses predict that, among the three species, L. zacynthium will face the highest risk of extinction within the next 50 years. Knowledge of the biology of these species provides data essential for identifying critical factors for their survival and for proposing targeted conservation measures.
- Published
- 2024
- Full Text
- View/download PDF
39. Ecological and social dimensions of raptor translocations
- Author
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Marino, F., Hodgson, Dave, and McDonald, Robbie
- Subjects
Conservation Conflicts ,Conservation Social Science ,Conservation Translocations ,Discourse Networks ,Hen Harrier ,Population Viability Analysis ,Raptor Translocations ,Step Selection Analysis ,Translocation Science - Abstract
Conservation science is a relatively young crisis discipline facing a rapid and increasing global loss of biodiversity with anthropogenic causes. Despite its constant evolution, conservation science is still riddled with challenges and uncertainties related to understanding and measuring success as well as achieving effective multidisciplinarity. Conservation translocations, the human-mediated movements of wildlife species for conservation benefits, embody conservation science paradigms and the challenge of delivering positive outputs. Specifically, a wide range of socio-ecological factors and difficulties shape the outcomes of conservation translocations and reintroduction biology - the recent sub-discipline born to study these measures - is still struggling in engaging effectively with decision-making and consider their socio-ecological dimensions in an integrated way. Here, we investigated conservation translocations in their ecological and social dimensions, seeking to build a comprehensive understanding of how diverse factors can synergically shape translocation outcomes and, hence, success. We focused on conservation translocations targeting birds of prey (hereafter raptors), given their role in socio-ecological systems, their often-endangered status and, therefore, their resulting inclusion in many conservation translocations. In particular, we studied the proposed reintroduction of hen harriers Circus cyaneus to southern England (hereafter the Southern reintroduction), a locally-endangered species at the centre of a long-standing conservation conflict in the United Kingdom. We developed a multidimensional framework to study conservation translocations, where social and ecological dimensions are addressed at the individual and population levels. We used a multi-pronged approach based on the literature on raptor translocations as well as qualitative and quantitative data related to socio-political and ecological aspects of the Southern reintroduction. We found that success is yet to be fully conceptualised and investigated in a holistic way in the literature on raptor translocations. Rare definitions and assessments of success are biased towards ecological considerations even though the challenges most frequently reported by practitioners are socio-political. We advised on the need for a new evaluation framework, that considers the multiple dimensions of translocations while also acknowledging the subjective component of success definition and evaluation. Using Discourse Network Analysis, we identified characteristics and dynamics of the stakeholder debate on the conservation and management of hen harriers in the UK in national newspaper media. The debate is characterised by the presence of vocal stakeholders and has become more polarised over time. Stakeholder coalitions diverge, especially over a conservation measure (i.e. the brood management scheme), but also share common discursive ground in the form of emotional reactions associated with hen harriers and the acknowledged need for collaboration. Through means of participant observation and semi-structured interviews, we disclosed generally favourable perspectives of local stakeholders in Salisbury Plain on the Southern reintroduction. We found key aspects of the engagement practice such as types of engagement activities, timing, and team composition shape engagement and social processes. We showed how these aspects are linked to the positive transformative potential of the Southern reintroduction for the conservation conflict in the UK. We explored the movement behaviour of hen harriers from the reintroduction source population in France. Using Hidden Markov Models (HMMs) and Integrated Step Selection Analysis (ISSA) to analyse, we determined land cover preferences. These showed an overall preference for arable land with differences based on behavioural states (resident and dispersal) and sex. Arable land is also associated with hen harriers transitioning to a resident state. Finally, we developed a population viability modelling approach aimed at simulating socio-ecological realism. By using this novel individual-based model, we showed the potential viability and spatial distribution of the reintroduced population of hen harriers under increasingly informed and complex scenarios where female demographic traits and farming operations significantly affect population establishment. Our findings provide decision-makers, practitioners, and stakeholders involved in the Southern reintroduction with essential information that can be used to inform current and future stages of this conservation programme. Most importantly, we provided conservation practitioners and researchers with a novel multidimensional framework that can be used in conservation programmes, including but not limited to translocations, to investigate their socio-ecological dimensions at different scales. Overall, this work contributes to a better understanding of the roles of both ecological and social drivers in conservation translocations, concluding with the recommendation that redefining reintroduction biology to translocation science would result in a more representative acknowledgement of the broad range of factors influencing translocation success.
- Published
- 2023
40. Assessing population viability and management strategies for species recovery of the critically endangered Puerto Rican parrot.
- Author
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Faust, L. J., Martínez, T. M., Parsons, A. W., White, T. H. Jr., Valentin, R., Vélez‐Valentín, J., Ramos‐Güivas, B., Nelson, S. S., and Lopez, M.
- Subjects
- *
POPULATION viability analysis , *WILDLIFE recovery , *PREDATOR management , *ENDANGERED species , *GOAL (Psychology) - Abstract
Recovery of endangered species is challenging and lengthy, especially when it involves reintroduction and dynamic environmental conditions. Because managers often need to decide between many management strategies with uncertain outcomes, periodically assessing progress toward recovery using population viability analysis (PVA) can help guide decision‐making. We developed a PVA for the critically endangered Puerto Rican parrot (Amazona vittata) to evaluate current status and potential future management strategies to reach goals set in the Recovery Plan. Having grown from their nadir of 13 birds in 1976 to 686 in 2021, the recovery effort has made great progress. Using 15 years of data, we built an individual‐based PVA that included interactions between two captive and three wild populations connected via annual releases. If management continues as planned, the wild populations have no to moderate risks of extinction (0–32%) over the next 100 years. However, wild populations remain dependent on releases to sustain growth, and recovery targets for stable population growth and connectivity have not yet been reached. Our analysis suggests that hurricanes are an impediment to reaching recovery targets and impact some wild populations more than others based on geography. Projections with climate‐change‐induced higher hurricane impact resulted in wild populations being less likely to stabilize. We identified demographic rates and associated management strategies that could positively impact wild populations: increasing reproduction (e.g., via increasing artificial nests, improving nest success) and decreasing first‐year mortality (e.g., via targeted predator control). Based on our current understanding of Puerto Rican parrot demographics, species recovery will continue to be management‐dependent unless demographic rates can be altered. As more data are gathered, especially for data‐sparse populations and in the face of environmental change, future iterations of this model can re‐evaluate progress, update management strategies, and provide support for deciding if and when to delist this iconic species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. Shifting baselines clarify the impact of contemporary logging on forest‐dependent threatened species.
- Author
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Ward, Michelle, Ashman, Kita, Lindenmayer, David B., Legge, Sarah, Kindler, Gareth, Cadman, Timothy, Fletcher, Rachel, Whiterod, Nick, Lintermans, Mark, Zylstra, Philip, Stewart, Romola, Thomas, Hannah, Blanch, Stuart, and Watson, James E. M.
- Subjects
- *
ENVIRONMENTAL degradation , *CLIMATE change mitigation , *ECOLOGICAL integrity , *DEFORESTATION , *ENVIRONMENTAL policy , *POPULATION viability analysis , *ILLEGAL logging - Abstract
Despite the importance of protecting forests and woodlands to achieve global climate and biodiversity goals, logging impacts persist worldwide. Forestry advocates often downplay these impacts but rarely consider the cumulative threat deforestation and degradation has had, and continues to have, on biodiversity. Using New South Wales (Australia) as a case study, we quantify the extent of deforestation and degradation from 1788 (pre‐European colonization) to 2021. We used historical loss as a baseline to evaluate recent logging (2000–2022) and the condition of the remaining native forest and woodland. Condition was quantified by measuring the similarity of a current ecosystem to a historical reference state with high ecological integrity. Using these data, we measured the impacts on 269 threatened terrestrial species. We show that possibly over half (29 million ha) of pre‐1788 native forest and woodland vegetation in NSW has been lost. Of the remaining 25 million ha, 9 million ha is estimated to be degraded. We found recent logging potentially impacted 150 species that had already been affected by this historical deforestation and degradation, but the impacts varied across species. Forty‐three species that were identified as impacted by historical deforestation and degradation and continue to be impacted by logging, now have ≤50% of their pre‐1788 extent remaining that is intact and nine species now have ≤30%. Our research contextualizes the impact of current logging against historical deforestation and highlights deficiencies in environmental assessments that ignore historical baselines. Future land management must consider both the extent and condition of remaining habitat based on pre‐1788 extents. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Friend or foe? Engaging public can save the critically endangered common hamster (Cricetus cricetus).
- Author
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Szapu, Julianna Szulamit, Lanszki, József, Pongrácz, Péter, and Cserkész, Tamás
- Subjects
- *
WILDLIFE conservation , *KEYSTONE species , *NATURE conservation , *ENDANGERED species , *CURRENT distribution , *POPULATION viability analysis - Abstract
The common hamster (Cricetus cricetus) occupies a controversial position among mammals inhabiting agricultural areas, as it is possibly the only critically endangered species that is legally targeted by lethal control methods, making it a conflict‐generating pest. We surveyed various stakeholders, agrarian consultants, wildlife rangers, and residents for the first time in Hungary, with two interrelated questionnaires to obtain accurate information about hamster populations, and to learn about the participants knowledge of, and attitude toward hamsters in order to provide fundamental information for planning and strengthening social embeddedness. Additionally, we prepared the current distribution map of the hamster. Based on the relatively wide distribution and locally high abundance of the species, Hungary has a key role in hamster conservation. We identified several factors, which can contribute to successful species protection. The results indicated that more than 60% of the respondent's liked hamsters. In contrast, only a few residents considered hamsters in their settlement to be beneficial. Our results suggest that the hamster's reputation is disproportionately negative due to vaguely known perceptions of harm as compared with actual reported damage. This imbalance could be rectified through enhanced communication efforts. Improving the species' reputation is integral to effective species conservation initiatives. Current pest control practices (poisons and snap traps) kill the hamsters, even though 82% of the residents would prefer to keep the hamsters alive, conforming to conservation efforts. The results also indicated that the hamster could be a flagship species in Hungary. Knowledge of the protected status of the hamster predicted a positive attitude toward the species and related to nature conservation consciousness. We conclude that requirements of residents should be included in the species action plan along with the experts' knowledge, as this could contribute to successful, long‐term conservation of the hamster. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Conservation biology of three threatened Limonium species endemic to Zakynthos Island (Ionian Islands, Greece).
- Author
-
Valli, Anna-Thalassini, Papaioannou, Charikleia, Liveri, Eleni, Papasotiropoulos, Vasileios, and Trigas, Panayiotis
- Subjects
LIFE history theory ,GENETIC variation ,ENDANGERED species ,CONSERVATION biology ,ENDEMIC species - Abstract
Knowledge of the life history traits, reproductive biology and demography of rare species is fundamental for their conservation, yet plant population monitoring is uncommon. The restricted ranges of the Limonium species endemic to the Mediterranean area, combined with the vulnerability of their specialized littoral habitats, indicate the need for appropriate conservation measures. We evaluate the conservation status and estimate the future extinction risk of three Limonium species endemic to Zakynthos Island in the Ionian Islands, Greece (Limonium korakonisicum , Limonium phitosianum and Limonium zacynthium) using 5 years of monitoring data. We compile information on their geographical distribution, population dynamics, reproductive biology and genetic diversity. Population sizes and survival rates of seedlings exhibited marked annual fluctuations, although fecundity and relative reproductive success remained high throughout the monitoring period. We observed a dominance of mature individuals in all three species, indicating their increased tolerance to salinity. Three subpopulations each of L. phitosianum and L. zacynthium were genotyped using five microsatellite loci. The observed number of alleles and the low gene flow value potentially indicate reduced genetic diversity, inbreeding, and limited gene flow within and among subpopulations of both species. Based on the IUCN categories and criteria, we assess L. korakonisicum as Critically Endangered, L. phitosianum as Near Threatened and L. zacynthium as Endangered. Population viability analyses predict that, among the three species, L. zacynthium will face the highest risk of extinction within the next 50 years. Knowledge of the biology of these species provides data essential for identifying critical factors for their survival and for proposing targeted conservation measures. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. Approaching the mystery of aging by the epigenetic clock.
- Author
-
Inoue-Murayama, Miho
- Subjects
BIOLOGICAL extinction ,POPULATION viability analysis ,LIFE history theory ,OLDER people ,AGE ,MACAQUES ,GORILLA (Genus) - Abstract
The article discusses the challenges of accurately determining the age of animals, both in captivity and in the wild. The author, a researcher at the Wildlife Research Center of Kyoto University, explains how DNA analysis can provide valuable information about animal age and life events. The article focuses on the use of methylation analysis, a method that examines changes in DNA methylation patterns to estimate age. The author presents examples of age estimation in various species, including primates, bears, and dolphins, and highlights the potential applications of this technology in conservation efforts. The article concludes by emphasizing the need for further research to develop non-invasive age estimation methods for a wide range of animal species. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
45. Visualizing the risk landscape to adaptively increase post-release survival of translocated Galliformes.
- Author
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Nelson, Shelley L., Saher, D. Joanne, Huang, John, McKinnon, Donald T., Coleing, Amelia, Griebel, Ilsa A., Wellicome, Troy I., Moehrenschlager, Axel, and Heinrichs, Julie A.
- Subjects
CAPTIVITY ,GALLIFORMES ,SAGE grouse ,ENVIRONMENTAL risk ,MORTALITY risk factors ,POPULATION viability analysis ,SURVIVAL rate - Abstract
Translocation of captive-bred animals is a widely used conservation strategy to support the recovery of imperiled wild populations. Identifying which factors enhance or limit survival after release can be important in adapting translocation strategies, particularly for species with low survival rates after release from captivity. Many translocation programs track post-translocation survival, but few complete spatial-statistical assessments of mortality risk associated with release environments. Typically, few animals are released from captive breeding programs, limiting the sample size available for analyses. We aimed to create a workflow that used limited datasets to evaluate the influence of spatial conditions and other factors on mortality risk. Greater sage-grouse (Centrocercus urophasianus) are endangered in Canada and of conservation concern throughout their range in the United States. After the species declined precipitously in Canada, a captive breeding program was initiated with subsequent releases in Alberta and Saskatchewan. Despite success in captive breeding, mortality rates of released sage-grouse were high. We used GPS- and VHF-based locations of released sage-grouse to determine how spatial features influence mortality risk of sage-grouse after release from captivity. We implemented a multistep approach to quantify and map risk relative to the environmental features associated with mortality. We also assessed whether the movement behaviors of sage-grouse correspond with environmental risk factors by using a combination of survival models and integrated step-selection functions. Mortality of sage-grouse in Alberta was hastened in areas close to anthropogenic disturbance. Although birds in Alberta avoided areas of higher mortality risk, those in Saskatchewan did not, perhaps due to environmental and selection constraints. This multistep approach allowed us to utilize small sample sizes to assess key risk factors in the landscape. This process supports the adaptive modification of translocation plans and can similarly support other data-limited scientists and managers in assessing environmental mortality risk and defining conservation actions for endangered species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Characterization of forest fragments occupied by the critically endangered and endemic San Martín titi monkey (Plecturocebus oenanthe).
- Author
-
Vargas, Carina Linda Rubio, Cancharis, Zoila Lasmit Cerón, and Heymann, Eckhard W.
- Subjects
FOREST density ,MONKEYS ,FRAGMENTED landscapes ,REMOTE-sensing images ,GENE flow ,POPULATION viability analysis - Abstract
This study describes the characteristics of forest fragments occupied by a Critically Endangered endemic Peruvian primate, the San Martín titi monkey, Plecturocebus oenanthe (Pitheciidae; Platyrrhini). We selected 45 fragments; 20 had already been surveyed in 2015 by the Proyecto Mono Tocón (six of these had been further split, resulting in 27 fragments); an additional 18 fragments were randomly selected from satellite images. We surveyed these fragments for the presence of P. oenanthe and determined characteristics of the fragments (size, shape, tree density, canopy height) and of the landscape (distance to nearest fragment and road). We also examined changes in the number of fragments and in forest cover between 2015 and 2019. We encountered P. oenanthe in all surveyed fragments except for the smallest one (0.2 ha). Our findings suggest that P. oenanthe can persist in fragments with a wide range of characteristics, particularly with regard to size and tree density. Unless fragmentation continues and overall forest cover in the area diminishes further, the species may be able to persist even in a fragmented landscape, provided that the matrix allows for movements between fragments. However, persistence might not be long-term if groups are not reproductive, populations become too small, and reduced gene flow results in inbreeding. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Human-carnivore conflict mitigation and lion population viability in Uganda's Queen Elizabeth National Park.
- Author
-
Schwartz, Michael W.
- Subjects
BRITISH kings & rulers ,QUEENS ,LEOPARD ,LIONS ,NATIONAL parks & reserves ,POPULATION viability analysis ,ROADKILL ,LIVESTOCK breeds - Abstract
The Uganda Carnivore Program (UCP), located in Queen Elizabeth National Park (QENP), has--among other large carnivore research and conservation measures--engaged in human-carnivore conflict mitigation and prevention efforts since 2015. UCP's experiential lion tourism program funds compensation to local communities for livestock losses to promote carnivore tolerance and conservation. But while UCP's conflict mitigation and prevention trials--through direct payments in response to forensically determined cases of livestock depredation by lion (Panthera leo)--may be aiding in the goal of maintaining lion viability in QENP and the greater Queen Elizabeth Conservation Area (QECA), compensation does not preclude ongoing challenges. These include unsustainable resource uses from human population growth and illegal expansions, subsequent land use changes, illegal livestock grazing and related husbandry practices, and compensation financing shortages. Of note regarding compensation is assessing whether claims of livestock depredation are genuine or not. Nevertheless, disruption to UCP's experiential lion tourism and compensation programs could result in increased retaliatory killings of lions, thus further reducing an already low lion population. As compensation includes the area's large carnivore guild, disruption could also mean further reductions in leopard (Panthera pardus) andspottedhyena (Crocuta crocuta) populations from retaliatory killings. Based on a perspective of UCP's compensation trials and related challenges, several recommendations, including the introduction of compensation percentage rates based on rewards-based frameworks, would strengthen human-carnivore conflict mitigation as part of lion and other large carnivore conservation. This would benefit QENP, greater QECA, and other protected areas where people, livestock, and large carnivores share space. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Consolidating diverse modeling methods and spatial prioritization for multispecies connectivity planning.
- Author
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Bohnett, Eve, Oetting, Jon, Noss, Reed, O'Brien, Michael, Frakes, Robert, Smith, Dan, Lockhart, Sarah, Mullinax, Jennifer, Poor, Erin E., Scheick, Brian, and Hoctor, Thomas
- Subjects
NATURE reserves ,URBAN growth ,FRAGMENTED landscapes ,PUMAS ,CORRIDORS (Ecology) ,POPULATION viability analysis ,LANDSCAPE design ,LANDSCAPE architecture - Abstract
Introduction: Given the different life histories and movement behaviors of diverse species, reconciling conservation measures to benefit all species is a critical concern for landscape conservation planning. Understanding land cover composition and finding multispecies movement routes across heterogeneous landscapes are crucial to maintaining many target species. The primary objectives of this study were to determine the optimal environment in Florida that promotes multispecies connectivity in landscapes increasingly threatened by rapid suburban development and to enhance methods for delineating the state's ecological networks. Methods: Potential functional connectivity of the focal species with statewide distributions and are considered priorities because of the historical and current threats to their population viability, such as the Florida black bear (Ursus americanus floridanus), Florida panther (Puma concolor coryi), eastern indigo snake (Drymarchon couperi), and southern fox squirrel (Sciurus niger niger), were modeled using Linkage Mapper, Omniscape, and resistant kernels. We combined quantiles from each method for a single species combination approach to leverage the results from the three models for planning purposes. Subsequently, we integrated the results into a novel multiple species, multimodel connectivity mapping approach. Following the corridor analysis, a comparison was made between multispecies connectivity maps, current managed conservation lands, and the main priority areas for the Florida Wildlife Corridor, a previously developed planning network of natural hubs and corridors. Finally, we used the spatial prioritization software Zonation to identify areas of conservation priority, while also illustrating the impacts of infrastructure (built infrastructure, roadways, mining, and future development 2040 and 2070 projections) and threats from human activity (landscape fragmentation, recreation, pollution, contamination, and clean-up sites). Results: The study identified priority areas for all four species, with a particular focus on areas not currently protected. The connectivity models showed significant overlap with current managed conservation lands and the main priority areas for the Florida Wildlife Corridor. Pinchpoint areas or bottlenecks were identified as needing fine-scale incorporation into spatial planning. Using the spatial prioritization software Zonation, we identified areas of conservation priority and illustrated the impacts of infrastructure and threats. Discussion: The results indicate that species-relevant connectivity models incorporating a group of focal species with both complementary and opposing habitat requirements can better inform biodiversity conservation and landscape design decisions. This multi-model approach provides a robust framework for identifying and prioritizing areas for conservation, particularly in landscapes facing rapid suburban development. Integrating multispecies connectivity models into conservation planning can enhance the effectiveness of ecological networks and contribute to the long-term viability of diverse species in Florida. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Small translocations of endangered Gallinula galeata sandvicensis (Hawaiian Common Gallinule) may be sufficient to generate a viable reintroduced population.
- Author
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Rees, Charles B van and Reed, J Michael
- Subjects
- *
POPULATION viability analysis , *BIOLOGICAL extinction , *WETLAND conservation , *ENDANGERED species , *WETLAND management - Abstract
Where stable source populations of at-risk species exist, translocation may be a reasonable strategy for re-establishing extirpated populations. However, the success rates of such efforts are mixed, necessitating thorough preliminary investigation. Stochastic population modeling can be a useful method of assessing the potential success of translocations. Here, we report on the results of modeling translocation success for the Gallinula galeata sandvicensis or 'alae 'ula (Hawaiian Common Gallinule), an endangered waterbird endemic to the Hawaiian Islands. Using updated vital rates, we constructed a model simulating 3 existing extant (wild) source populations and a hypothetical recipient site on another island. We then projected the effects of 6 different translocation scenarios and sensitivity of the results to variation of three important demographic parameters on the probability of extinction (PE) of the reintroduced and donor populations. Larger translocations, of at least 30 birds, had low probability of extinction in the reintroduced population, but raised extinction risk of the smallest source population. Spacing out translocations in time (e.g. 10 birds translocated in total in 3 installments over 9 years), led to lower PE than translocating all individuals at once (i.e. bulk translocations) for both the source and reintroduced populations. Brood size and hatch-year juvenile survival had a disproportionate impact on reintroduced population viability. Importantly, the reported juvenile survival rate is very near the threshold for population failure. This suggests that post-introduction and subsequent management of wetlands, particularly predator control, could be critical to reintroduction success. We recommend that individuals should be translocated from multiple, genetically distinct subpopulations to reduce the possibility of inbreeding depression. Based on this analysis, the recipient wetland should be sufficiently large that it can support at least 25 pairs of gallinules. Based on recent estimates of population densities on O'ahu, such a wetland would need to be between 3.75 and 74.6 ha. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Modeling the population dynamics and movement of Zebra mussels.
- Author
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Lacy, Alexanderia, Jin, Yu, Strayer, David, and Lenhart, Suzanne
- Subjects
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ZEBRA mussel , *ORDINARY differential equations , *LIFE cycles (Biology) , *DIFFERENTIAL equations , *POPULATION viability analysis - Abstract
Zebra mussels have caused significant damage in many lakes and rivers. By using a hybrid population model with discrete-time equations and ordinary differential equations, we represent the zebra mussel's life cycle, growth, and population movement. The dynamics of the larvae (unsettled and settled larvae) are represented during the summer months in a system of two ordinary differential equations, while the juvenile, small adult, and large adult stages are represented by a discrete model with yearly time steps. The goal is to investigate the effects of zebra mussel movement between three different spatial locations and possible control measures. Zebra mussel data and temperature values from three locations in the Hudson River over several years were used to estimate model parameters. We investigate the stability and net reproductive number for our model. We illustrate numerically the hybrid population model for several scenarios of movement and cleaning boats to remove mussels. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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