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Red spruce (Picea rubens Sarg.) is a commercially and ecologically important conifer species that primarily exists at northern latitudes of eastern North America and extends southward following the Appalachian Mountains into North Carolina and Tennessee. Due to a warming climate and human-caused disturbances, only fragmented, sky-island populations remain at the highest peaks of the southern Appalachians where their habitat continues to be threatened. While they have been recognized for the rare wildlife habitat they provide in the region, these populations remain understudied. This work aimed to examine differences in stem form between the northern and southern populations of red spruce and to provide additional quantitative methods for managing red spruce stands through providing regionally fitted stem taper models. First, we examined differences in stem form using two methods: a sectional rate of change in diameter and a region variable added to the Kozak (2004) Model 02 taper model. The sectional taper comparison showed significant differences (P  < .05) in taper rate throughout the stem that were most pronounced below breast height and above the midpoint. The nested model comparison also showed a significant difference after performing a likelihood ratio test. These results agreed that significant differences in stem form between the two populations exist and supported the idea that localized taper models would provide the best results. Next, we evaluated four stem taper models for their ability to predict upper stem diameters and total volume in southern Appalachian red spruce: a quadratic polynomial, a segmented, a variable exponent, and a geometric model. Fitting data came from a 1992 study across three southern Appalachian spruce-fir sites. Validation data came from a new dataset collected in 2022 at Unaka Mountain, Tennessee. Based on past studies and our results, we found that the Kozak (My last words on taper equations. For Chron 2004;80:507–15. https://doi.org/10.5558/tfc80507-4.) Model 02 variable exponent and the Max and Burkhart (Segmented polynomial regression applied to taper equations. For Sci 1976;22:283–9.) segmented polynomial models performed equally well. The choice of the final model should depend on the users' objectives and practical limitations (i.e. programming ability, availability of fitting data, error tolerance). [ABSTRACT FROM AUTHOR]

Site fidelity—returning repeatedly to the same site—can help many migratory species reduce uncertainty in their environment, especially when migratory stopover periods leave little time to explore and evaluate new habitat. Avian taxa, though, have shown wide variation in their levels of site fidelity during migration, and few studies have been able to examine individual-level fidelity at fine spatiotemporal scales. We used a high-resolution GPS tracking dataset of Numenius phaeopus (Whimbrel), a long-distance migratory shorebird, to assess levels of fidelity to specific foraging and roosting sites during migration, both within and between stopover seasons. We found that individuals are almost exclusively faithful to one shared roost site at night, but disperse to individual foraging territories during the day that overlap with each other by <20%. Individuals remain faithful to these distinct territories over time, on average shifting the center of their daily home ranges by <1.5 km within a single season, and overlapping with their previous season's home range by 70% when they return during subsequent stopovers. Our findings reveal for the first time that a shorebird species exhibits fine-scale, individual foraging site fidelity during and between migratory stopovers—an important insight to inform effective conservation and management action. [ABSTRACT FROM AUTHOR]

Arthroleptidae are an ecologically diverse group of sub-Saharan frogs. Arthroleptid tadpoles predominately occur in slow flowing to torrent waters. Their musculoskeletal system and the relationship between tadpole morphology and lifestyle are poorly understood. Here, we investigated the cranial morphology of four arthroleptid tadpoles occurring in different microhabitats: Leptopelis parkeri , Astylosternus occidentalis , Trichobatrachus robustus , and Nyctibates corrugatus. The crania of the tadpoles of A. occidentalis , N. corrugatus , and T. robustus are highly modified relative to L. parkeri , with wide and partly or completely fused cornua trabeculae, a fused cartilago labialis superior, as well as several modifications of the palatoquadrate, such as a broad commissura quadratocranialis and a processus ventralis which expands the surface for the origin of the large m. orbitohyoideus. The processus hyoquadratis is an evolutionary novelty, forming a functional unit together with the ceratohyale in the cranium of N. corrugatus. Finally, we compared the cranial morphology of these arthroleptids to other lotic and non-lotic species. Although the processus ventralis is not a generalized feature of the cranium in lotic species, it is not present in lentic species. [ABSTRACT FROM AUTHOR]

The article discusses the importance of restoring peatlands to sustain biodiversity and mitigate climate change. Peatlands store a significant amount of carbon and are home to diverse wildlife and flora. However, peatlands are under threat globally due to mining and agriculture, leading to the release of carbon dioxide into the atmosphere. Efforts to restore degraded peatlands are underway in various countries, with a focus on rewetting the land to create healthy ecosystems. The restoration of peatlands has shown positive results in revitalizing landscapes, protecting water resources, and supporting biodiversity. [Extracted from the article]

The evolutionary history and taxonomy of the Leopardus tigrinus species complex have been studied based on several approaches, mostly employing genetic and morphological data, leading to distinct classification schemes. We approached this problem from an ecological perspective, with 2 main goals: (i) to evaluate ecological niche differences among regional L. tigrinus populations to determine the extent of ecological divergence among them; and (ii) to identify environmental barriers to historical dispersal that could have driven differentiation among the proposed groups. We modeled the ecological niche of all taxonomic/geographic groups proposed so far to comprise the L. tigrinus complex using the Maximum Entropy algorithm, and evaluated geographic and ecological niche differences among them. Furthermore, we investigated possible environmental barriers to historical dispersal that could have driven differentiation among regional groups. We evaluated 4 hypothetical barriers across 3 time periods to assess their potential historical effect. We found high ecological divergence between northeastern tigrina populations and the northern Andean and Central American tigrinas. Other groups within the L. tigrinus complex are less divergent. In addition, the Guiana Shield tigrina, where the type locality of the species is located, seems to be ecologically similar to populations from northeastern Brazil while also showing some overlap with Andean populations. The Panama center, the Llanos of Colombia and Venezuela, and the Amazon region were identified as historical barriers for tigrina dispersal across all time periods. The inferred historical barriers and ecological divergence observed in this study contribute to the inference of evolutionary differentiation among geographic groups comprising the L. tigrinus complex, revealing areas of consistently low habitat suitability that have likely contributed to divergence among regional populations. [ABSTRACT FROM AUTHOR]

Space use by small mammals should mirror their immediate needs for food and predator shelters but can also be influenced by seasonal changes in biotic and abiotic factors. Lemmings are keystone species of the tundra food web, but information on their spatial distribution in relation to habitat heterogeneity is still scant, especially at a fine scale. In this study, we used spatially explicit capture–recapture methods to determine how topography, hydrology, vegetation, and soil characteristics influence the fine-scale spatial variations in summer density of brown lemmings (Lemmus trimucronatus). Lemmings were monitored throughout the summer in wet and mesic tundra habitats and in a predator exclusion grid, which was also located in mesic tundra. We found that in wet tundra, lemming densities were higher at sites with a rugged topography dominated by hummocks, but only during snow melt. In both mesic tundra sites, lemming densities were higher in sites with poor drainage and low aspect throughout the summer. We found no clear association between lemming densities and any tested vegetation or soil variables. Overall, hydrology and topography appear to play a dominant role in small-scale space use of brown lemmings with a secondary role for predator avoidance and food plant abundance. [ABSTRACT FROM AUTHOR]

Fungal primary pathogenicity on vertebrates is here described as a deliberate strategy where the host plays a role in increasing the species' fitness. Opportunism is defined as the coincidental survival of an individual strain in host tissue using properties that are designed for life in an entirely different habitat. In that case, the host's infection control is largely based on innate immunity, and the etiologic agent is not transmitted after infection, and thus fungal evolution is not possible. Primary pathogens encompass two types, depending on their mode of transmission. Environmental pathogens have a double life cycle, and tend to become enzootic, adapted to a preferred host in a particular habitat. In contrast, pathogens that have a host-to-host transmission pattern are prone to shift to a neighboring, immunologically naive host, potentially leading to epidemics. Beyond these prototypical life cycles, some environmental fungi are able to make large leaps between dissimilar hosts/habitats, probably due to the similarity of key factors enabling survival in an entirely different niche, and thus allowing a change from opportunistic to primary pathogenicity. Mostly, such factors seem to be associated with extremotolerance. [ABSTRACT FROM AUTHOR]

Adaptation to new habitats might facilitate species' range shifts in response to climate change. In 2005, we transplanted experimental populations of coastal dune plant Camissoniopsis cheiranthifolia into 4 sites within and 1 site beyond its poleward range limit. Beyond-range transplants had high fitness but often delayed reproduction. To test for adaptation associated with experimental range expansion, we transplanted descendants from beyond- and within-range populations after 10 generations in situ into 2 sites within the range, 1 at the range edge, and 2 sites beyond the range. We expected to detect adaptation to beyond-range conditions due to substantial genetic variation within experimental populations and environmental variation among sites. However, individuals from beyond-range experimental populations were not fitter than those from within the range when planted at either beyond-range site, indicating no adaptation to the beyond-range site or beyond-range environments in general. Beyond-range descendants also did not suffer lower fitness within the range. Although reproduction was again delayed beyond the range, late reproduction was not favored more strongly beyond than within the range, and beyond-range descendants did not delay reproduction more than within-range descendants. Persistence in beyond-range environments may not require adaptation, which could allow a rapid response to climate change. [ABSTRACT FROM AUTHOR]

Many coastal marine species have discontinuous distributions or genetic breakpoints throughout their geographical ranges. These spatial and genetic disjunctions occur in species that span limited to broad dispersal potential. Thus, the mechanisms that underlie these disjunctions remain speculative or incompletely known, particularly on small spatial scales where long-term historical processes are unlikely to be the only mechanism contributing to disjunction. Rather, ecological or oceanographic factors may be important. To identify key drivers of coastal disjunctions, we reviewed publications investigating spatial and genetic disjunctions in coastal marine species and visually summarized where and why they are thought to occur. The most frequently cited mechanisms implicated in causing disjunctions include historical processes, oceanographic features, heterogeneous habitat, species introductions, and limited larval dispersal capacities. However, the relative importance of each of these processes varies depending on the spatial scales investigated. Furthermore, locations associated with disjunctions for a suite of species are typically associated with multiple processes that maintain these disjunctions. This study provides a non-exhaustive synthesis of disjunctions in coastal marine species by visualizing where they occur, exploring underlying mechanisms, and investigating biases in how the scientific community studies this phenomenon. [ABSTRACT FROM AUTHOR]

Old-growth forests harbor a large amount of complex structural features that result in a wide array of wildlife habitats. However, intensive forest management is gradually converting old-growth forest into younger, even-aged stands, reducing structural complexity and threatening the persistence of old-growth-dependent species. Maintaining elements of complex stand structure is critical to the conservation of old-growth forest specialists that use different habitat components at different periods of their annual cycle, and it requires a comprehensive understanding of seasonal variation in the habitat needs of these species. However, difficulties in observing free-ranging animals have sometimes limited our ability to assess such variations in habitat requirements, especially for small, elusive species. To address this, we used GPS telemetry collars to describe fine-scale habitat selection patterns of 6 male American Martens (Martes americana) during 2 contrasting periods of the year (snow-free, from mid-April to mid-November; snow-covered, from mid-November to mid-April), an objective formerly hard to achieve using conventional VHF telemetry. We used resource selection functions conducted at the fourth order of selection to compare habitat characteristics found at the sites used by martens (GPS locations, n = 100) to those found on an equal number of available sites (random points, n = 100) within each individual seasonal home range. We conducted vegetation surveys on these 200 sites to describe habitat and built candidate models representing different concurrent hypotheses. Our results showed that proxies of prey availability, predator avoidance, and thermal constraints were the primary factors influencing marten habitat selection during both periods, although their respective importance differed between periods. Martens selected sites with a high density of large-diameter snags (≥30·ha−1), high conifer canopy closure (≥53%), and a dense lateral cover (≥81%) during the snow-free period, but selected sites with a high volume of coarse woody debris (≥64 m3·ha−1) and high conifer canopy closure (≥48%) during the snow-covered period. Our results highlight the importance of contrasting seasonal changes in habitat selection patterns of small carnivores and may help maintain structural attributes in the landscape that are suitable for male American Martens. [ABSTRACT FROM AUTHOR]

Microbiomes, the complex networks of micro-organisms and the molecules through which they interact, play a crucial role in health and ecology. Over at least the past two decades, engineering biology has made significant progress, impacting the bio-based industry, health, and environmental sectors; but has only recently begun to explore the engineering of microbial ecosystems. The creation of synthetic microbial communities presents opportunities to help us understand the dynamics of wild ecosystems, learn how to manipulate and interact with existing microbiomes for therapeutic and other purposes, and to create entirely new microbial communities capable of undertaking tasks for industrial biology. Here, we describe how synthetic ecosystems can be constructed and controlled, focusing on how the available methods and interaction mechanisms facilitate the regulation of community composition and output. While experimental decisions are dictated by intended applications, the vast number of tools available suggests great opportunity for researchers to develop a diverse array of novel microbial ecosystems. [ABSTRACT FROM AUTHOR]

All non-Mimosoid nodulated genera in the legume subfamily Caesalpinioideae confine their rhizobial symbionts within cell wall-bound 'fixation threads' (FTs). The exception is the large genus Chamaecrista in which shrubs and subshrubs house their rhizobial bacteroids more intimately within symbiosomes, whereas large trees have FTs. This study aimed to unravel the evolutionary relationships between Chamaecrista growth habit, habitat, nodule bacteroid type, and rhizobial genotype. The growth habit, bacteroid anatomy, and rhizobial symbionts of 30 nodulated Chamaecrista species native to different biomes in the Brazilian state of Bahia, a major centre of diversity for the genus, was plotted onto an ITS- trnL-F -derived phylogeny of Chamaecrista. The bacteroids from most of the Chamaecrista species examined were enclosed in symbiosomes (SYM-type nodules), but those in arborescent species in the section Apoucouita , at the base of the genus, were enclosed in cell wall material containing homogalacturonan (HG) and cellulose (FT-type nodules). Most symbionts were Bradyrhizobium genotypes grouped according to the growth habits of their hosts, but the tree, C. eitenorum , was nodulated by Paraburkholderia. Chamaecrista has a range of growth habits that allow it to occupy several different biomes and to co-evolve with a wide range of (mainly) bradyrhizobial symbionts. FTs represent a less intimate symbiosis linked with nodulation losses, so the evolution of SYM-type nodules by most Chamaecrista species may have (i) aided the genus-wide retention of nodulation, and (ii) assisted in its rapid speciation and radiation out of the rainforest into more diverse and challenging habitats. [ABSTRACT FROM AUTHOR]

This article comments on: Casaes PA, Ferreira dos Santos JM, Silva VC, Rhem MFK, Teixeira Cota MM, de Faria SM, Rando JG, James EK, Gross E. 2024. The radiation of nodulated Chamaecrista species from the rainforest into more diverse habitats has been accompanied by a reduction in growth form and a shift from fixation threads to symbiosomes. Journal of Experimental Botany 75, 3643–3662. [ABSTRACT FROM AUTHOR]

Shelter is one critical aspect of an animal's habitat, providing refuge from predators and weather, protection for offspring, and aiding in physiological homeostasis. During the day, bats find shelter in roosts—spaces created under tree bark, in tree cavities, or between rocks—after spending the night searching for food. Finding a roost with a microclimate that enables bats to remain in their thermoneutral zone could reduce energetic demands or allow bats to allocate energy to other activities such as reproduction and fighting disease. We aimed to characterize the structural features and microclimate (i.e. temperature) of roosts used by male Little Brown Myotis (Myotis lucifugus) during the summer and determine whether bats select certain characteristics disproportionally to what is available at different spatial scales. During the summers of 2017 and 2018, we radio-tracked 34 male M. lucifugus in Lodgepole Pine-dominated forests. We located at least 1 roost for 20 individuals (average = 2.85 roosts/bat, range = 1 to 6). Although snags were available, most of the roosts were in rock features (86% in rocks, 14% in trees or snags). Male M. lucifugus were more likely to select rock roosts with less canopy closure that were closer to water compared to available roosts on the landscape. They also selected roosts in rock features occurring within larger areas of rock cover that had wider entrances and access to crevices that faced the sky; these roosts also had warmer microclimates relative to other locations available on the landscape. Crevices that allow the bat to bask in the sun and change locations within a roost, minimizing energy needed for active thermoregulation, could be very beneficial for individuals recovering from diseases such as white-nose syndrome. Our work indicates that rock features provide habitat for male M. lucifugus during summer; other studies have shown that bats roost in these features during autumn and winter, further supporting their importance. By protecting these important rock structures, managers can help bats meet their habitat needs throughout the year. [ABSTRACT FROM AUTHOR]

Human presence and activities have profoundly altered animals' habitats, exposing them to greater risks but also providing new opportunities and resources. The animals' capacity to effectively navigate and strike a balance between risks and benefits is crucial for their survival in the Anthropocene era. Red foxes (Vulpes vulpes), adept urban dwellers, exhibit behavioral plasticity in human-altered environments. We investigated variations in detection frequency on trail cameras and the behavioral responses (explorative, bold, and fearful) of wild red foxes living along an urbanization gradient when exposed to a metal bin initially presented clean and then filled with anthropogenic food. All fox populations displayed an increased interest and similar explorative behavioral responses toward the anthropogenic food source, irrespective of the urbanization gradient. Despite no impact on explorative behaviors, foxes in more urbanized areas initially showed heightened fear toward the empty bin, indicating increased apprehension toward novel objects. However, this fear diminished over time, and in the presence of food, urban foxes displayed slightly reduced fear compared with their less urban counterparts. Our results highlight foxes' potential for adaptability to human landscapes, additionally underscoring the nuanced interplay of fear and explorative behavioral response of populations living along the urbanization gradient. [ABSTRACT FROM AUTHOR]

Abstract. Land-use change and tourism development have seriously threatened the ecosystems of coastal protection forests and beaches. Light and nutrients are spatially heterogeneously distributed between the two ecosystems. Clonal plants, such as Calystegia soldanella , which play a crucial role in maintaining the ecological stability of coastal habitats, are likely to encounter diverse environments. In this study, we investigated clonal integration and the division of labour in C. soldanella under heterogeneous (high nutrient and low light [HNLL]; low nutrient and high light [LNHL]) and homogeneous habitats. We cultivated pairs of connected and severed ramets of C. soldanella in these environments. Our results showed the total biomass (TB) of connected ramets was higher than that of severed ramets in heterogeneous environments, suggesting clonal integration enhances growth in heterogeneous habitats. The root shoot ratio was significantly lower in HNLL than in LNHL conditions for connected ramets, demonstrating a division of labour in growth under heterogeneous conditions. However, parameters of clonal propagation of C. soldanella did not significantly differ between connected and severed ramets in heterogeneous environments, indicating no division of labour in clonal propagation. In homogeneous environments, the growth of C. soldanella did not benefit from clonal integration. Connected ramets in heterogeneous habitats exhibited higher TB than in homogeneous habitats. The TB of one ramet in HNLL was consistently higher than that in LNHL, irrespective of ramet's states, which suggests that high soil nutrients may enhance the growth. We conclude that C. soldanella has the capability of clonal integration to achieve high biomass in heterogeneous but not in homogeneous conditions, and the establishment of coastal protection forests (high nutrient and low light) may foster the growth of C. soldanella. [ABSTRACT FROM AUTHOR]

Fomes fomentarius is a widespread, wood-rotting fungus of temperate, broadleaved forests. Although the fruiting bodies of F. fomentarius persist for multiple years, little is known about its associated microbiome or how these recalcitrant structures are ultimately decomposed. Here we used metagenomics and metatranscriptomics to analyse the microbial community associated with healthy living and decomposing F. fomentarius fruiting bodies to assess the functional potential of the fruiting body-associated microbiome and to determine the main players involved in fruiting body decomposition. F. fomentarius sequences in the metagenomes were replaced by bacterial sequences as the fruiting body decomposed. Most CAZymes expressed in decomposing fruiting bodies targeted components of the fungal cell wall with almost all chitin-targeting sequences, plus a high proportion of beta-glucan-targeting sequences, belonging to Arthropoda. We suggest that decomposing fruiting bodies of F. fomentarius represent a habitat rich in bacteria, while its decomposition is primarily driven by Arthropoda. Decomposing fruiting bodies thus represent a specific habitat supporting both microorganisms and microfauna. [ABSTRACT FROM AUTHOR]

In most colony-breeding species, biparental care during both egg incubation and chick-rearing is inevitable for successful reproduction, requiring parents to coordinate their nest attendance and foraging time. The extent to which the rhythm of nest attendance is adjusted to temporal and spatial variation in food availability is poorly understood. Here, we investigate whether the rhythm of nest attendance interacts with the spatial and temporal availability of foraging habitats in Eurasian spoonbills Platalea leucorodia breeding on Schiermonnikoog, a Dutch Wadden Sea barrier island. Spoonbills are tactile foragers that forage during both day and night in habitats of varying salinity. GPS-tracking combined with acceleration-based behavioral classification of 9 female and 13 male adult spoonbills between 2013 and 2019 revealed that, despite nearby foraging opportunities following a tidal rhythm, nest attendance followed a sex-specific diel rhythm. During incubation and chick-rearing, females attended the nest at night and foraged during the day, while males showed the reverse rhythm. Females made more and shorter foraging trips to, almost exclusively, nearby marine habitats, whereas the larger males often made long trips to forage in more distant freshwater habitats. Before and after breeding, females as well as males foraged primarily at night, suggesting that this is the preferred period of foraging for both sexes. Nevertheless, foraging habitat use remained sex-specific, being most likely explained by size-dependent foraging techniques. To conclude, the sex-specific rhythm of nest attendance is not shaped by the spatial and temporal availability of foraging habitats. [ABSTRACT FROM AUTHOR]

Sexual dimorphism can evolve in response to sex-specific selection pressures that vary across habitats. We studied sexual differences in subterranean amphipods Niphargus living in shallow subterranean habitats (close to the surface), cave streams (intermediate), and cave lakes (deepest and most isolated). These three habitats differ because at greater depths there is lower food availability, reduced predation, and weaker seasonality. Additionally, species near the surface have a near-even adult sex ratio (ASR), whereas species from cave lakes have a female-biased ASR. We hypothesized (a) a decrease in sexual dimorphism from shallow subterranean habitats to cave lake species because of weaker sexual selection derived from changes in the ASR and (b) an increase in female body size in cave lakes because of stronger fecundity selection on account of oligotrophy, reduced predation, and weaker seasonality. We measured body size and two sexually dimorphic abdominal appendages for all 31 species and several behaviours related to male competition (activity, risk-taking, exploration) for 12 species. Species with an equal ASR that live close to the surface exhibited sexual dimorphism in all three morphological traits, but not in behaviour. The body size of females increased from the surface to cave lakes, but no such trend was observed in males. In cave lake species, males and females differed neither morphologically nor behaviourally. Our results are consistent with the possibility that sexual and fecundity selection covary across the three habitats, which indirectly and directly, respectively, shape the degree of sexual dimorphism in Niphargus species. [ABSTRACT FROM AUTHOR]

Ground squirrels act as important members of grassland ecosystems by serving as both ecosystem engineers and as a prey base for carnivores. There is mounting evidence that climate change is driving ground squirrel population declines. We resurveyed 54 historical localities throughout the Wyoming Basin and western Colorado where Wyoming Ground Squirrel (Urocitellus elegans) specimens were collected to investigate if climate change was driving extirpations at these historically occupied sites. We detected extirpations at 12 sites and used binomial generalized linear models in an information-theoretic framework to investigate if climate change was associated with these extirpations. Additionally, we investigated if land cover change was associated with persistence and if land cover ameliorated or exacerbated the effects of climate change. We found that changes in climate, especially increasingly dry summer air and increasing mean summer temperatures, were associated with a reduced probability that U. elegans persisted at a historically occupied site. In addition, we found that current forest cover at a site and increasing rangeland cover at the regional level were associated with reduced probability that U. elegans persisted, although these associations were weaker than the climate associations. The effects of climate change and land cover change did not interact. Our findings build on mounting evidence that montane-associated ground squirrels throughout the Western United States are negatively impacted by climate change. The reduction in ground squirrel abundance or their extirpation due to climate change could lead to changes in ecosystem structure or reductions in trophic complexity. [ABSTRACT FROM AUTHOR]

Duckweeds span 36 species of free-floating aquatic organisms with body sizes ranging from 2 mm to 10 mm, where each plant body plan is reduced to a largely leaf-like structure. As an emerging crop, their fast growth rates offer potential for cultivation in closed systems. We describe a novel UK collection derived from low light (dLL) or high light (dHL) habitats, profiled for growth, photosynthesis, and photoprotection (non-photochemical quenching, NPQ) responses. Twenty-three accessions of three Lemna species and one Spirodela polyrhiza were grown under relatively low light (LL: 100 μmol m–2 s–1) and high light (HL: 350 μmol m–2 s–1) intensities. We observed broad within- and between-species level variation in photosynthesis acclimation. Duckweeds grown under HL exhibited a lower growth rate, biomass, chlorophyll, and quantum yield of photosynthesis. In HL compared with LL, carotenoid de-epoxidation state and NPQ were higher, whilst PSII efficiency (φPSII) and Chl a : b ratios were unchanged. The dLL plants showed relatively stronger acclimation to HL compared with dHL plants, especially Lemna japonica accessions. These achieved faster growth in HL with concurrent higher carotenoid levels and NPQ, and less degradation of chlorophyll. We conclude that these data support local adaptation to the light environment in duckweed affecting acclimation in controlled conditions. [ABSTRACT FROM AUTHOR]

The persistence of non-neutral trait polymorphism is enigmatic because stabilizing selection is expected to deplete variation. In cryptically coloured prey, negative frequency-dependent selection due to search image formation by predators has been proposed to favour rare variants, promoting polymorphism. However, in a heterogeneous environment, locally varying disruptive selection favours patch type-specific optima, resulting in spatial segregation of colour variants. Here, we address whether negative frequency-dependent selection can overcome selection posed by habitat heterogeneity to promote local polymorphism using an individual-based model. In addition, we compare how prey and predator mobility may modify the outcome. Our model revealed that frequency-dependent predation could strongly promote local prey polymorphism, but only when differences between morphs in patch-specific fitness were small. The effect of frequency-dependent predation depended on the predator adjustment of search image and was hampered by the prey population structure. Gene flow due to prey movement counteracted local selection, promoted local polymorphism to some extent, and relaxed the conditions for polymorphism due to frequency-dependent predation. Importantly, abrupt spatial changes in morph frequencies decreased the probability that mobile frequency-dependent predators could maintain local prey polymorphism. Overall, our study suggests that in a spatially heterogeneous environment, negative frequency-dependent selection may help maintain local polymorphism but only under a limited range of conditions. [ABSTRACT FROM AUTHOR]

Heliozoans are ambush protists that inhabit most limnetic systems. However, ecological information about planktonic heliozoans is still limited. In this study, we investigated seasonal changes in planktonic heliozoan abundance in the deep northern and shallow southern basins of Lake Biwa at pelagic stations between August 2020 and December 2021. We compared planktonic heliozoan abundance levels between the two basins and examined the relationship between heliozoan abundance and environmental variables. In both basins, high levels of planktonic heliozoan abundance were detected in autumn, winter and spring. In the south basin, there was a significant positive correlation between planktonic heliozoan abundance and chlorophyll a concentration as well as the abundance of the diatoms Aulacoseira granulata and Aulacoseira ambigua. These results suggest that planktonic heliozoans directly or indirectly consume diatoms and that heliozoan abundance is subjected to bottom-up control. Furthermore, planktonic heliozoan abundance in the south basin was higher than that in the north basin, possibly due to the presence of waterweeds, which can serve as habitat for heliozoans, and the redistribution of planktonic heliozoans through resuspension from lake bottom sediments. [ABSTRACT FROM AUTHOR]

Global biodiversity is increasingly threatened by the spread of invasive species. Understanding the mechanisms influencing the initial colonization and persistence of invaders is therefore needed if conservation actions are to prevent new invasions or strive to slow their spread. The Eurasian Collared-Dove (Streptopelia decaocto, EUCO) is one of the most successful avian invasive species in North America; however, to our knowledge, no study has simultaneously examined the role that climate-matching, human activity, directional propagation, and local density have in this invasion process. Our research expands upon a cellular-automata-based hierarchical model developed to assess directional invasion dynamics to further quantify the impacts of climate, elevation, and land cover type on the spread of EUCO in North America. Our results suggest that EUCO's dispersal patterns can largely be explained by the effects of habitat, climate, and environmental conditions at different stages of the invasion process rather than some innate preferred north-westerly spread. Specifically, EUCO initially colonized warm and wet grassland habitats and tended to persist in urban areas. We also found that while EUCO were more likely to spread to the northeast of existing habitats, directional preference did not drive persistence and recolonization events. These findings highlight the importance of incorporating both neighborhood effects and environmental factors in the modelling of range-expanding species, adding to the toolset available to researchers to model invasive species spread. Further, our research demonstrates that historical records of invasive species occurrences can provide the data resources needed to disentangle the characteristics driving species invasion and enable predictions that are of critical importance to resource managers. [ABSTRACT FROM AUTHOR]

The Home Owners' Loan Corporation (HOLC) was a U.S. government-sponsored program initiated in the 1930s to evaluate mortgage lending risk. The program resulted in hand-drawn "security risk" maps intended to grade sections of cities where investment should be focused (greenlined areas) or limited (redlined zones). The security maps have since been widely criticized as being inherently racist and have been associated with high levels of segregation and lower levels of green amenities in cities across the country. Our goal was to explore the potential legacy effects of the HOLC grading practice on birds, their habitat, and the people who may experience them throughout a metropolis where the security risk maps were widely applied, Greater Los Angeles, California (L.A.). We used ground-collected, remotely sensed, and census data and descriptive and predictive modeling approaches to address our goal. Patterns of bird habitat and avian communities strongly aligned with the luxury-effect phenomenon, where green amenities were more robust, and bird communities were more diverse and abundant in the wealthiest parts of L.A. Our analysis also revealed potential legacy effects from the HOLC grading practice. Associations between bird habitat features and avian communities in redlined and greenlined zones were generally stronger than in areas of L.A. that did not experience the HOLC grading, in part because redlined zones, which included some of the poorest locations of L.A., had the highest levels of dense urban conditions (e.g., impervious surface cover), whereas greenlined zones, which included some of the wealthiest areas of the city, had the highest levels of green amenities (e.g., tree canopy cover). The White population of L.A., which constitutes the highest percentage of a racial or ethnic group in greenlined areas, was aligned with a considerably greater abundance of birds affiliated with natural habitat features (e.g., trees and shrubs). Conversely, the Hispanic or Latino population, which is dominant in redlined zones, was positively related to a significantly greater abundance of synanthropic birds, which are species associated with dense urban conditions. Our results suggest that historical redlining and contemporary patterns of income inequality are associated with distinct avifaunal communities and their habitat, which potentially influence the human experience of these components of biodiversity throughout L.A. Redlined zones and low-income residential areas that were not graded by the HOLC can particularly benefit from deliberate urban greening and habitat enhancement projects, which would likely carry over to benefit birds and humans. [ABSTRACT FROM AUTHOR]

Plumage coloration arises from a complex concert of selection pressures incorporating regional ecology, the light environment and genomic architecture. Here, we analyse the evolution of coloration in cardinals and grosbeaks (Cardinalidae) from the avian visual perspective and test the relative roles of life-history traits in shaping plumage evolution. We incorporate life-history data from three separate sources to analyse the correlated evolution of plumage coloration and ecological and habitat classifications for males and females. Our results show that males and females evolve under different axes of selection and that correlations with life-history traits differ between the sexes. We find that preferences for semi-open, fragmented habitat are correlated with male, but not female, plumage complexity. We also find that migration, long heralded as a driver of sexual dichromatism, is correlated with reduced plumage complexity in females, but not significantly correlated with male plumage coloration. Finally, our results showcase that user-defined categorical metrics can influence or, potentially, even mislead the interpretation of results, highlighting the need to measure habitat quantitatively rather than with subjective, categorical metrics. [ABSTRACT FROM AUTHOR]

Studies of selected habitat conditions, as well as spatiotemporal variability of the number and selected traits of individuals of the species Arum alpinum were carried out in 2020–2021 in the foothills of the Western Carpathians. The investigations were conducted in permanent patches located in the Golesz nature reserve (Patch I), near the village of Markowce (Patch II), in the Kozigarb nature reserve (Patch III), and near the village of Żółków (Patch IV). Patches I and III were established in a Tilio cordatae–Carpinetum betuli oak–hornbeam forest with undergrowth dominated by low-growth vegetation with narrow leaves, whereas Patches II and IV were established in a Populetum albae riparian forest with undergrowth dominated by broad-leaved species. The most abundant population of A. alpinum was noted in Patch I, but substantial numbers of both vegetative and reproductive individuals were also present in Patches II and IV. The occurrence of temporal variability of individual traits increased from its lowest level in Patch IV, through Patches I and II, to its highest level in Patch III. The significant positive correlation in all populations between length of petioles and blade dimensions, as well as between length of generative stems and infructescence traits confirmed previous findings. Moreover, we showed that A. alpinum was not closely affiliated with a specific forest community. Significant shading and moist nutrient-rich soils are suitable for this species, while dry soils and excessive insolation may limit the flowering and fruiting of individuals. [ABSTRACT FROM AUTHOR]

Our understanding of Amazonian biogeography is quickly increasing, catalyzed by the growing use of genomic datasets, improved knowledge of species distributions, and the accumulation of new data on the geological and climatic history of the region. The high number of species in Amazonia and their intricate patterns of geographic distribution triggered the development of many diversification hypotheses that shaped historical biogeography as a discipline. Here, we present a historical overview of avian biogeographic studies in Amazonia, their recent advances, outstanding questions, and future directions. We focus on how new approaches have led to novel understandings of the distribution patterns and diversification processes that underpin avian diversity. We show how genomic tools are being used to establish new hypotheses about the drivers of diversification and highlight the importance of recent studies of birds in previously overlooked environments, such as floodplains and open vegetation enclaves. We emphasize the importance of gene flow, species traits, and habitat affinities in studying diversification processes to fully acknowledge the complexity of Amazonian ecosystems and their history. We then discuss the current gaps in Amazonian taxonomic and biogeographic knowledge, with a focus on the issues that we believe hinder our understanding of the field. Amazonia has been facing increasing levels of forest loss due to agricultural expansion, infrastructure development, mining, climate change, and illegal activities catalyzed by weak governance. To halt biodiversity loss, it is crucial to increase our knowledge of the natural history and biogeography of Amazonian species. We suggest increasing incentives for research and training at institutions based in the region, as well as the establishment of partnerships with governments, local communities, NGOs, and international institutions to bring diverse communities together to address crucial questions. [ABSTRACT FROM AUTHOR]

Little is known about the ecology of early instars of most aquatic insects, particularly their associations with microhabitat (<1 m2) features, such as sediment size distributions, other abiotic parameters, and the overall invertebrate community. This study sought to explore correlations between various biotic and abiotic parameters of a southern Colorado stream and the presence of early instars of Epeorus longimanus (Eaton) (Ephemeroptera: Heptageniidae). A total of 18 samples collected in 2007 and 2013 using a Hess sampler in riffle habitats were used to correlate the size of individuals with biological and abiotic characteristics of the stream, including sediment size, periphyton biomass, entrained organic matter, and the remainder of the benthic invertebrate community, all of which were measured using material from within the sampler. Results from both years showed that early instars of E. longimanus were more likely to be found in areas with smaller sediment sizes, higher live periphyton biomass (but lower overall organic matter), and lower densities of invertebrate predators. [ABSTRACT FROM AUTHOR]

Pollinators, which provide vital services to wild ecosystems and agricultural crops, are facing global declines and habitat loss. As undeveloped land becomes increasingly scarce, much focus has been directed recently to roadsides as potential target zones for providing floral resources to pollinators. Roadsides, however, are risky places for pollinators, with threats from vehicle collisions, toxic pollutants, mowing, herbicides, and more. Although these threats have been investigated, most studies have yet to quantify the costs and benefits of roadsides to pollinators and, therefore, do not address whether the costs outweigh the benefits for pollinator populations using roadside habitats. In this article, we address how, when, and under what conditions roadside habitats may benefit or harm pollinators, reviewing existing knowledge and recommending practical questions that managers and policymakers should consider when planning pollinator-focused roadside management. [ABSTRACT FROM AUTHOR]

Urban environments are novel alternative habitats for wildlife. Anthropogenic food resources such as supplemental feeding (SF) are usually abundant, stable across seasons, and sometimes rich in calories. Although anthropogenic food resources could modify the seasonality and composition of the diets of urban animals, previous studies have been limited to qualitative assessments based on stomach content and food remains. Our study compared diet seasonality and niche width between rural and urban populations of Eurasian red squirrels (Sciurus vulgaris) in Hokkaido, Japan, using direct observation and stable isotope analysis. We found that dietary seasonality was lower in urban populations than in rural populations. The frequency of seed use was higher throughout the year in urban populations than in rural populations, possibly because of excessive seeds by SF in urban squirrels. Additionally, female body weights of the urban population were higher than those of the rural population. However, this was not true for males. Because high body weight can increase reproductive success in females, it is feasible that diet modification could contribute to population growth in urban squirrels. However, no differences in male body weight were observed, possibly due to energy loss caused by intense male–male competition at feeding sites. Our study highlights the importance of studying the multidimensional effects of anthropogenic foods on wildlife. [ABSTRACT FROM AUTHOR]

Understanding habitat selection is fundamental to addressing the response of a species to disturbance. Because resources are unevenly distributed across the landscape, habitat selection occurs at multiple scales. We used capture–mark–recapture and radiotelemetry techniques to quantify the macrohabitat and microhabitat associations that define space use of the Southern Red-backed Vole (Myodes gapperi) in northeastern forests. Macrohabitat characteristics were evaluated at the scale of the forest stand by comparing conditions between visited and unvisited trap stations and suggest red-backed voles have an affinity for locations with higher basal area of Eastern Hemlock (Tsuga canadensis) and more coarse woody material. For microhabitat characteristics we modeled the influence of forest structure, ground cover, and geographic features on home range, specifically core area placement. We found that Southern Red-backed Vole core areas were associated with higher Red Maple (Acer rubrum) basal area, deeper leaf litter, greater density of hemlock stems, and closer proximity to water. The affinity of southern red-backed voles for eastern hemlock raises questions about population persistence and shifts in distribution as eastern hemlock stands are replaced by hardwood stands following infestation by Hemlock Woolly Adelgid. [ABSTRACT FROM AUTHOR]

Eelgrass meadows provide vital nearshore habitats and ecosystem services, but they have declined from human stressors and conservation efforts are now widespread. Dynamic ecosystems like eelgrass meadows naturally rearrange as disturbance and recruitment unfold across seascapes. However, some decisions that protect eelgrass only consider extant meadows, thus ignoring the potential for change. Here, we report decades of eelgrass dynamics observed across the northeast Pacific. Our observations support conservation expanded to the seascape scale, which includes potentially inhabitable areas along with extant meadows. We found that total seascape meadow area changed over time, and changes within seascapes were often asynchronous. Some meadows rearranged across seascapes over multiple kilometres and decades. Also, some seascapes compartmentalized meadow collapse, which enabled later recovery, or supported local recruitment that substantially increased total meadow area. These observations were consistent with hierarchical patch dynamics, which promote ecosystem persistence over larger space and time scales. Thus, to enable the dynamics that underpin eelgrass persistence, it is necessary to keep many eelgrass habitat options open across seascapes, rather than protect only extant meadows. Given that dynamic, hierarchical ecosystems are common along marine shorelines, this approach may be effective for both nearshore ecosystems in general and for eelgrass in particular. [ABSTRACT FROM AUTHOR]

Torpor was traditionally seen as a winter survival mechanism employed by animals living in cold and highly seasonal habitats. Although we now know that torpor is also used by tropical and subtropical species, and in response to a variety of triggers, torpor is still largely viewed as a highly controlled, seasonal mechanism shown by Northern hemisphere species. To scrutinize this view, we report data from a macroanalysis in which we characterized the type and seasonality of torpor use from mammal species currently known to use torpor. Our findings suggest that predictable, seasonal torpor patterns reported for Northern temperate and polar species are highly derived forms of torpor expression, whereas the more opportunistic and variable forms of torpor that we see in tropical and subtropical species are likely closer to the patterns expressed by ancestral mammals. Our data emphasize that the torpor patterns observed in the tropics and subtropics should be considered the norm and not the exception. [ABSTRACT FROM AUTHOR]

The simplification of forest structural complexity, caused by anthropogenic land-use practices, is one of the main threats to understory specialist birds. We examined the association of both single structural attributes and structural complexity, with the density of 4 understory bird species in the Global Biodiversity Hotspot "Chilean Winter Rainfall-Valdivian Forests" of South America. Between 2011 and 2013, we surveyed habitat attributes and conducted bird point counts in 505 plots in Andean temperate ecosystems in Chile. In each habitat plot, we measured understory density, volume of coarse woody debris (CWD), number of snags, diameter at breast height (DBH) of trees, and leaf litter depth. With these attributes, we developed an index of stand structural complexity (ISC). On average, old-growth forests had higher values for understory density, CWD volume, DBH, and litter depth than secondary forests and open fields, and thus greater values of ISC. The density of understory birds was positively correlated with the ISC for the Rhinocryptidae Pteroptochos tarnii, Scelorchilus rubecula, and Scytalopus magellanicus. We also found a positive association between understory density and litter depth, with the density of the Furnariidae Sylviorthorhynchus desmursii. However, this latter species showed a negative association with the density of snags. Our results suggest the utility of using an index of structural complexity, rather than single or even additive habitat attributes, for determining the density of understory specialist birds. We recommend that management plans should promote the retention of habitat attributes that contribute to the structural complexity of temperate forests of South America and beyond. [ABSTRACT FROM AUTHOR]

Understanding nest site selection is critical to developing effective conservation management actions. The Superb Lyrebird (Menura novaehollandiae) is one of many endemic species extensively impacted by Australia's unprecedented 2019-2020 megafires. Over a period of 5 months, an estimated 43% of the entire range of this slow-breeding species was burnt, with the biggest impact on the central subspecies M. n. novaehollandiae (55%). Four months prior to these megafires, we conducted a field study of nest site habitat selection in the Superb Lyrebird within the Greater Blue Mountains World Heritage Area (15,400 km²): a key stronghold of the central subspecies of the Superb Lyrebird. We found that at the local scale, lyrebird nest sites were more likely to be found in habitats characterized by dense canopy trees and rich in rainforest elements such as vines and treeferns. At the landscape scale, lyrebird nests were most likely to be constructed in rainforest; this firesensitive habitat type made up only 1% of the Greater Blue Mountains World Heritage Area. The probability of nest occurrence also increased with slope. We also found that >74% of all nesting habitat within the Greater Blue Mountains World Heritage Area burned in the 2019-2020 megafires, including 80% of areas of high suitability for nesting. These results suggest that the impact of these megafires on Superb Lyrebirds may be greater than currently thought. Given the importance of rainforest as nesting habitat for the Superb Lyrebird, managers should prioritize its restoration and protect it from future fire events. More broadly, our results illustrate how large-scale catastrophic events-such as megafires-can disproportionately affect habitats critical to specific points within an organism's life cycle. [ABSTRACT FROM AUTHOR]

Although carry-over effects related to wintering habitat quality are known to influence population dynamics of migratory songbirds, the presence of breeding season carry-over is understudied in full annual cycle models. To test whether forest fragment size on the breeding grounds can impose negative carry-over effects on a migratory songbird, we fitted adult Wood Thrush (Hylocichla mustelina) with 1-year coded radio-tags in forest fragments ranging from 16 to 499 ha in southwestern Ontario during the 2016-2019 breeding seasons and utilized automated telemetry via the Motus Wildlife Tracking System to record fall migration timing and returns the following spring (apparent annual survival). To examine short-term effects of fragment size on breeding females, during the 2018 and 2019 breeding seasons, we collected blood samples during incubation to measure corticosterone levels and tracked complete reproductive success and nest timing. We found that Wood Thrushes breeding in small forest fragments were not subject to strong negative effects on body condition (mass, corticosterone), reproductive success, or timing of the last nest of the season. We found that the onset of fall migration departure was not delayed for birds nesting in small fragments, and that apparent annual survival was not linked to breeding fragment size. This suggests that habitat differences linked to fragment size were not strong enough to trigger the kinds of negative carry-over effects (delayed migration, lower reproductive success) that have been documented in other species as a result of poor wintering-ground habitat quality. The strength of breeding fragment size-induced seasonal carry-over remains a critical gap in full annual cycle models for other declining migratory songbirds. Our findings suggest that while the importance of preserving large forested areas is often prioritized in conservation projects, small forest fragments can also have high conservation value. [ABSTRACT FROM AUTHOR]

Juvenile survival in birds is difficult to estimate, but this vital rate can be an important consideration for management decisions. We estimated juvenile survival of cooperatively breeding Florida Scrub-Jays (Aphelocoma coerulescens) in a landscape degraded by fire suppression and fragmentation using data from marked (n = 325) and unmarked juveniles (n = 1,306) with an integrated hierarchical Bayesian model. To assess the combined analyses, we also analyzed these datasets separately, with a Cormack-Jolly-Seber model (marked) and young model (unmarked). Our data consisted of monthly censuses of territorial family groups from Florida Scrub-Jay populations in East Central Florida collected over a 22-year period. Juvenile survival was estimated from July when young Florida Scrub-Jays begin developing independence to March when they become first-year individuals and grouped according to the habitat quality class of their natal territory that were based on shrub height (with intermediate shrub heights being optimal and short and tall shrub heights being suboptimal) and the presence of sandy openings (the preferred open having many sandy openings; closed not having enough). Parameter estimates in the combined analysis were intermediate to the separate analyses. Notable differences among the separate analyses were that suboptimal habitat survival was lower in the unmarked analysis, the unmarked analysis showed a linear effect of time not seen in the marked analysis, and there was an effect of male breeder death in the marked but not unmarked analysis. The combined data analysis provided more inference than did either dataset analyzed separately including juveniles in optimal-closed territories unexpectedly had higher survival than those in optimal-open, survival increased through time, and male breeder death had a negative effect on survival. This study suggests that optimal-closed habitat may play an important role in juvenile Florida Scrub-Jay survival perhaps by providing better cover from predators and warrants further investigation for management implications. [ABSTRACT FROM AUTHOR]

Determining factors that shape a species' population genetic structure is beneficial for identifying effective conservation practices. We assessed population structure and genetic diversity for Saltmarsh Sparrow (Ammospiza caudacuta), an imperiled tidal marsh specialist, using 13 microsatellite markers and 964 individuals sampled from 24 marshes across the breeding range. We show that Saltmarsh Sparrow populations are structured regionally by isolation-by-distance, with gene flow occurring among marshes within ~110 to 135 km of one another. Isolation-by-resistance and isolation-by-environment also shape genetic variation; several habitat and landscape features are associated with genetic diversity and genetic divergence among populations. Human development in the surrounding landscape isolates breeding marshes, reducing genetic diversity, and increasing population genetic divergence, while surrounding marshland and patch habitat quality (proportion high marsh and sea-level-rise trend) have the opposite effect. The distance of the breeding marsh to the Atlantic Ocean also influences genetic variation, with marshes farther inland being more divergent than coastal marshes. In northern marshes, hybridization with Nelson's Sparrow (A. nelsoni) strongly influences Saltmarsh Sparrow genetic variation, by increasing genetic diversity in the population; this has a concomitant effect of increasing genetic differentiation of marshes with high levels of introgression. From a conservation perspective, we found that the majority of population clusters have low effective population sizes, suggesting a lack of resiliency. To conserve the representative breadth of genetic and ecological diversity and to ensure redundancy of populations, it will be important to protect a diversity of marsh types across the latitudinal gradient of the species range, including multiple inland, coastal, and urban populations, which we have shown to exhibit signals of genetic differentiation. It will also require maintaining connectivity at a regional level, by promoting high marsh habitat at the scale of gene flow (~130 km), while also ensuring "stepping stone" populations across the range. [ABSTRACT FROM AUTHOR]

The microbiome of Greenland Ice Sheet supraglacial habitats is still underinvestigated, and as a result there is a lack of representative genomes from these environments. In this study, we investigated the supraglacial microbiome through a combination of culturing-dependent and -independent approaches. We explored ice, cryoconite, biofilm, and snow biodiversity to answer: (1) how microbial diversity differs between supraglacial habitats, (2) if obtained bacterial genomes reflect dominant community members, and (3) how culturing versus high throughput sequencing changes our observations of microbial diversity in supraglacial habitats. Genomes acquired through metagenomic sequencing (133 high-quality MAGs) and whole genome sequencing (73 bacterial isolates) were compared to the metagenome assemblies to investigate abundance within the total environmental DNA. Isolates obtained in this study were not dominant taxa in the habitat they were sampled from, in contrast to the obtained MAGs. We demonstrate here the advantages of using metagenome SSU rRNA genes to reflect whole-community diversity. Additionally, we demonstrate a proof-of-concept of the application of in situ culturing in a supraglacial setting. [ABSTRACT FROM AUTHOR]

Avian vocalizations have evolved in response to a variety of abiotic and biotic selective pressures. While there is some support for signal convergence in similar habitats that are attributed to adaptation to the acoustic properties of the environment (the "acoustic adaptation hypothesis," AAH), there is also evidence for character displacement as a result of competition for signal space among coexisting species (the "acoustic niche partitioning hypothesis"). We explored the acoustic space of avian assemblages distributed along six different habitat types (from herbaceous habitats to warm rainforests) in southeastern Queensland, Australia. We employed three acoustic diversity indices (acoustic richness, evenness, and divergence) to characterize the signal space. In addition, we quantified the phylogenetic and morphological structure (in terms of both body mass and beak size) of each community. Acoustic parameters showed a moderately low phylogenetic signal, indicating labile evolution. Although we did not find meaningful differences in acoustic diversity indices among habitat categories, there was a significant relationship between the regularity component (evenness) and vegetation height, indicating that acoustic signals are more evenly distributed in dense habitats. After accounting for differences in species richness, the volume of acoustic space (i.e. acoustic richness) decreased as the level of phylogenetic and morphological resemblance among species in a given community increased. Additionally, we found a significantly negative relationship between acoustic divergence and divergence in body mass indicating that the less different species are in their body mass, the more different their songs are likely to be. This implies the existence of acoustic niche partitioning at a community level. Overall, while we found mixed support for the AAH, our results suggest that community-level effects may play a role in structuring acoustic signals within avian communities in this region. This study shows that signal diversity estimated by diversity metrics of community ecology based on basic acoustic parameters can provide additional insight into the structure of animal vocalizations. [ABSTRACT FROM AUTHOR]

Green Peafowl stands as a landmark lawsuit in China where environmental NGOs successfully halted a project threatening habitat of endangered species. By examining this case, this analysis evaluates the promise and limitations of China's civil environmental public interest litigation (EPIL) in protecting habitat. Under civil EPIL's broad and flexible framework, environmental NGOs can convince the courts that a government-approved project would destroy the 'biological habitat' for endangered species and hold project developers accountable. By arguing that the environmental impact assessment (EIA) institution is jointly liable by preparing a flawed report, environmental NGOs can also use civil EPIL as an alternative avenue to challenge the quality of an approved EIA report. However, the timing of judicial intervention, uncertainties of litigation outcomes, the scope of protection, and the court's attitude towards EIA claims limit the effectiveness of civil EPIL. This analysis highlights the need to address regulatory failures revealed by Green Peafowl. [ABSTRACT FROM AUTHOR]

This case law overview comments on significant UK environmental law cases for the period 1 April 2022–31 March 2023. It begins with an overarching introduction, which draws some general themes from our selection of cases, focussing on the scope of environmental law, connections between private and public law disputes, and the standard of review in the public law context. It then addresses 12 significant cases concerning statutory trusts over land under section 164 of the Public Health Act 1875 and section 10 of the Open Spaces Act 1906, public rights on Dartmoor Commons, private nuisance, climate change, insurance, environmental impact assessment, delay in judicial review, forestry, contaminated land, and habitats. It ends with some final thoughts on this year's cases and the year ahead. [ABSTRACT FROM AUTHOR]

Wildlife monitoring plays a key role in species conservation, with growing importance under the threat of climate change. The Northern Pika (Ochotona hyperborea) is a cold-adapted species found in Hokkaido, Japan, presumably vulnerable to such threats. However, its high elusiveness hinders detailed population surveys, and visual detection methods—often used for other pika species—are not applicable to its densely vegetated habitats. In this study, we assessed the efficacy of aural detection methods to survey the occupancy of Northern Pika through their distinct vocalizations. We conducted two types of point-count surveys—auditory observation and playback—during 2021 at 18 sites in and around Daisetsuzan National Park. We then assessed the efficacy of these methods in detecting presence and compared time until first detection of the animal. The Northern Pika was present at 11 of all surveyed sites, with a predominance at higher elevations. Our results suggest that both auditory observation and playback are effective at detecting presence, but playback is more time-efficient. We discuss the advantages and disadvantages of each method given these results. In conclusion, our results demonstrate that both survey methods are applicable for Northern Pika population surveys—even in densely vegetated habitats—representing valid and affordable survey methods that can help to improve current monitoring and conservation efforts, and will be of increasing value given potentially negative effects of climate change on persistence of the species. [ABSTRACT FROM AUTHOR]

Cryptic species and their interactions are challenging to describe owing to the difficulties in observing and sampling their populations. Such methodological hurdles are critical to resolve, especially when important interactions involving poorly described species are detected. The red decorator crab, Schizophrys aspera , is a newfound predator of the corallivorous Pacific crown-of-thorns seastar (CoTS; Acanthaster sp.). We discuss the Indo-Pacific distribution and taxonomy of S. aspera and provide characterization of its cryptic population at sites around Heron Island, Great Barrier Reef, that differ in CoTS densities. Most S. aspera (>95%) were found under coral rubble pieces atop existing rubble, associated with large pieces and chasmic interstices. The three smallest individuals (carapace width: 5–11 mm) were found under rubble overlying sand. Mean density of S. aspera was 0.8 ± 0.2 ind. 100 m−2, which varied among sites. Areas with lower records of CoTS had higher densities of S. aspera (p  = 0.002; R 2 = 0.25), which justifies evaluation of the distribution and impact of this species in context of CoTS outbreaks. We present a method to survey cryptic decapods on coral reefs, along with microhabitat characteristics to help predict S. aspera on reefs prone to CoTS outbreaks and its capacity to act as a natural top-down control mechanism. [ABSTRACT FROM AUTHOR]

The Gulf of Maine hosts the southernmost remaining population of North American Atlantic salmon. Despite extensive hatchery supplementation since the late 1800s, and more recent riverine habitat restoration efforts and fishing restrictions, US-origin Atlantic salmon populations continue to decline and have remained at low abundance over recent decades. Climate change has been identified as a critical threat to the future of US Atlantic salmon. In this study, we synthesized available information on how habitats used by Atlantic salmon across all their life stages will be affected by climate change as well as the suitability of future conditions for salmon's persistence in the region. Maintaining sufficient cool water refugia during increasing summer temperatures in riverine habitats is required for sustaining salmon in the future. Changes in groundwater quantity and temperature, which will depend on future precipitation and temperature, will be critical factors for river temperatures, as will land use and land cover. While Atlantic salmon's freshwater life stages are heavily documented, the marine phase is relatively less studied. Climate models predict basin-scale changes over the next century, but impacts to salmon are difficult to predict. Furthermore, disparate drivers and differential rates of change between freshwater and marine habitats could present an obstacle to the transition between phases in the future. We have a general understanding of migration patterns and prey preferences but lack a clear picture of how salmon respond to habitat and ecosystem-level changes associated with climate change progression. More research to understand freshwater habitat changes and salmon's marine spatiotemporal distribution responses will enhance capacities to evaluate future risks and predict impacts of climate change to US-origin Atlantic salmon. [ABSTRACT FROM AUTHOR]

Typically, females and males are expected to have characteristic sexual strategies and patterns of size dimorphism, but these generalizations are subject to exceptions. The occurrence of atypical cases has been related to species or populations from environments under strong physical, ecological and/or social constraints. Allocosa marindia and Allocosa senex are two coastal spiders (Lycosidae: Allocosinae) with reversal in sex roles and sexual size dimorphism. Males are larger than females, and females are the mobile sex that initiates courtship. It is unclear whether the occurrence of non-typical sexual traits in Allocosinae spiders is correlated with coastal habitats. Our aim was to study sexual size dimorphism and surface mobility in Allocosinae spiders from different habitats throughout South America. We revised specimens from scientific collections and performed 3-day samplings to collect individuals and determine nocturnal surface mobility. We analysed a total of 1071 Allocosinae adult individuals from 18 species and/or morphotypes. Our results revealed new species inhabiting coastal habitats with reversal in sexual size dimorphism and higher nocturnal surface activity in females; however, not all coastal species shared those characteristics. Future studies will focus on studying other ecological, physiological and/or phylogenetic factors that could be shaping the origin and maintenance of sex role reversal in Allocosinae. [ABSTRACT FROM AUTHOR]

Mutualistic plant-pollinator interactions play a critical role in the diversification of flowering plants. The spatiotemporal correlates of such interactions can be understood in a phylogenetic context. Here, we generate ddRAD-seq data for the highly diverse Vriesea-Stigmatodon lineage to test for correlated trait evolution among pollination syndromes and life form, habitat type, and altitude. Our results show that pollination syndromes are correlated with changes in life form and habitat type. The ancestor of the Vriesea-Stigmatodon lineage was likely bat pollinated, rock dwelling and inhabited open, mid-elevation forests. Transitions from bat to hummingbird pollination are correlated with transitions to the epiphytic life form in shaded habitats, whereas bat pollination is correlated with the rock-dwelling life form and open habitats. Our dated phylogenetic tree reveals independent origins of hummingbird pollination, occurring twice in Vriesea at c. 5.8 and 5.4 Mya. The timing for the shifts in pollination syndrome coincides with geological and environmental transformations across the Serra do Mar Mountain Chain, which increased habitat heterogeneity where Vriesea and their mutualists diversified. The phylogenetic tree reinforces the non-monophyly of taxonomic sections within the genus Vriesea previously defined by flower morphology, indicating that some lineages should be treated as species complexes. This study identifies synergetic drivers of speciation in a tropical biodiversity hotspot. [ABSTRACT FROM AUTHOR]

We investigated the movements of European seabass, Dicentrarchus labrax , to understand habitat use and connectivity to evaluate how individual seabass are protected by the spatiotemporal fisheries restrictions in place. We tagged seabass with acoustic transmitters in a study area in the Port of Zeebrugge (Belgium) in the southern North Sea. The 370,200 detections of 57 seabass in the study area revealed high residency in the period from late March–May to September–November, as well as high site fidelity (70.7%). Whereas the majority of seabass left the area in winter, 13 seabass stayed in the harbour experiencing temperatures as low as 2.8°C. Two groups of seabass were identified having different core movement areas in the inner and outer harbours, although movement between the two areas was possible. The distinct differences in habitat use between these groups resulted in a significantly different level of exposure to fisheries under the same policy framework. By quantifying the level of protection of seabass, based on the spatiotemporal fisheries management in place, our study underlines the importance of taking into account movement behaviour when evaluating conservation measures. [ABSTRACT FROM AUTHOR]

The primary threat to biodiversity is habitat loss and degradation. Private residential land (yards) encompass large proportions of urban, suburban, and rural spaces and is among the most rapidly expanding systems on Earth. Yards also represent a conservation opportunity to provide wildlife habitat, support biodiversity, restore ecosystem function and ecosystem services, and increase local opportunities for people to connect with nature. In the present article, we propose a humanity for habitat stewardship practice by synthesizing the evidence-based yard management actions that can advance the conservation value of yards, with a focus on benefits to biodiversity, climate resiliency, and people. The magnitude and extent of yard management might differ, depending on the region, specific management practices, the yard's size, and the yard's location along the urban to rural gradient. We detail opportunities, challenges, and strategies for encouraging stronger public participation in conservation through yard stewardship to facilitate biodiversity-friendly residential landscapes that benefit wildlife and people. [ABSTRACT FROM AUTHOR]