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In the past two decades, drifting fish aggregation devices (FADs) have revolutionized pelagic fisheries, and are now responsible for the majority of tuna purse seine catches. Here, we argue that by taking advantage of the same proven aggregative properties, FADs could be used to enhance the benefits provided by blue water marine protected areas (MPAs). Using models of commercially targeted fish populations, we explore the potential benefits that could be achieved if unfished conservation FADs—designed as self‐powered devices capable of remaining semi‐stationary—were deployed within blue water MPAs. By increasing the residence time of exploited species in MPAs, conservation FADs will reduce average mortality rates. By increasing the local density of exploited species, they may also improve the function of ecosystems in blue water MPAs. Conservation FADs could, therefore, amplify the benefits of blue water MPAs. We find this amplification is largest in those contexts where blue water MPAs have attracted the most criticism—when their area is small compared to both the open ocean and the distribution of fish stocks that move through them. [ABSTRACT FROM AUTHOR]

Dispersal emerges as a consequence of how an individual's phenotype interacts with the environment. Not all dispersing individuals have the same phenotype, and variation among individuals can generate complex variation in the distribution of dispersal distances and directions. While active locomotion performance is an obvious candidate for a dispersal phenotype, its effects on dispersal are difficult to measure or predict, especially in small organisms dispersing in wind or currents. Therefore, we analyzed the effects of larval swimming on dispersal and settlement of coral‐reef fish larvae using a high‐resolution biophysical model. The model is, to date, the only biophysical model of marine larval dispersal that has been statistically validated against genetic parentage estimates of larval origin and destination, and incorporates empirically‐estimated larval behaviors and their ontogeny. Larval swimming, in combination with depth, orientation and navigation behaviors, actually reduced dispersal distances compared to those of passive larvae. Swimming had no consistent effects on long distance dispersal, but increased the spread of settlement locations. Swimming speed, in contrast, did not consistently affect median dispersal distances, but faster swimming larvae had greater mean and maximum dispersal distances than slower swimming larvae. Finally, faster larval swimming speeds consistently increased the probability of settlement. Our analysis shows how larval swimming differentially affects multiple properties of dispersal kernels. In doing so, it indicates how selection could favor faster larval swimming to increase settlement and local retention, which may actually result in longer dispersal distances as a by‐product of larvae trying to locate habitat rather than to disperse greater distances. [ABSTRACT FROM AUTHOR]

A shipwreck of the 3rd/2nd decade BC found near Comacchio (prov. Ferrara, Italy) in 1980 contained not only well-preserved technical equipment and commercial goods but also 102 Roman lead ingots. Since then, the origin of the ingots has been intensively discussed. Domergue et al. (2012) connected the epigraphic elements with lead isotope analyses and favored the southeastern Spanish lead ore mines being the source of the lead metal. An origin from the Balkan region (Illyricum) was favored by Dušanić (2008). Due to our investigations, both assumptions cannot be maintained. We present a new interpretation of the lead’s isotope signature which best match data of ore deposits from Chalkidiki, Thasos island, and Pangaion mountains in the northern Aegean region. [ABSTRACT FROM AUTHOR]

Marine fisheries are an essential component of global food security, but many are close to their limits and some are overfished. The models that guide themanagement of these fisheries almost always assume reproduction is proportional to mass (isometry), when fecundity generally increases disproportionately to mass (hyperallometry). Judged against several management reference points, we show that assuming isometry overestimates the replenishment potential of exploited fish stocks by 22% (range: 2% to 78%) for 32 of the world's largest fisheries, risking systematic overharvesting. We calculate that target catches based on assumptions of isometry are more than double those based on assumptions of hyperallometry for most species, such that common reference points are set twice as high as they should be tomaintain the target level of replenishment. We also show that hyperallometric reproduction provides opportunities for increasing the efficacy of tools that are underused in standard fisheries management, such as protected areas or harvest slot limits. Adopting management strategies that conserve large, hyperfecund fish may, in some instances, result in higher yields relative to traditional approaches. We recommend that future assessment of reference points and quotas include reproductive hyperallometry unless there is clear evidence that it does not occur in that species. [ABSTRACT FROM AUTHOR]

Bactrocera tryoni is a polyphagous fruit fly that is predicated to have continuous breeding in tropical and subtropical Australia as temperature and hosts are not limiting. Nevertheless, in both rainforest and tropical agricultural systems, the fly shows a distinct seasonal phenology pattern with an autumn decline and a spring emergence. Temperature based population models have limited predictive capacity for this species and so the driver(s) for the observed phenology patterns are unknown. Using a demographic approach, we studied the age-structure of B. tryoni populations in subtropical Australia in an agricultural system, with a focus on times of the year when marked changes in population abundance occur. We found that the age-structure of the population varied with season: summer and autumn populations were composed of mixed-age flies, while late-winter and early-spring populations were composed of old to very old individuals. When held at a constant temperature, the longevity of adult reference cohorts (obtained from field infested fruits) also showed strong seasonality; the adults of spring and early autumn populations were short-lived, while late autumn and late winter adults were long-lived. While still expressing in modified landscapes, the data strongly suggests that B. tryoni has an endogenous mechanism which would have allowed it to cope with changes in the breeding resources available in its endemic monsoonal rainforest habitat, when fruits would have been abundant in the late spring and summer (wet season), and rare or absent during late autumn and winter (dry season). [ABSTRACT FROM AUTHOR]

Covert rewilding is the secret and illegal translocation of species in the pursuit of conservation objectives. Recent history contains multiple covert rewilding events, frequently occurring after official permission was denied. In order to better understand the phenomenon, I formulate covert rewilding as an optimisation problem, with the goal of creating a population that is too large to be eradicated once it is detected. I then consider a hypothetical covert rewilding of Tasmanian devils Sarcophilus harrisii to the Australian mainland. Three different release locations would allow a covert devil population to remain undetected for years, by which time its size and distribution may preclude eradication. Optimal release locations also represent optimal locations for official surveillance, but a more effective approach to halting covert rewilding could be a more permissive stance towards legal rewilding. [ABSTRACT FROM AUTHOR]

Assisted migration is a controversial conservation measure that aims to protect threatened species by moving part of their population outside its natural range. Although this could save species from extinction, it also introduces a range of risks. The magnitude of the threat to recipient ecosystems has not been investigated quantitatively, despite being the most common criticism leveled at the action. We used an ensemble modeling framework to estimate the risks of assisted migration to existing species within ecosystems. With this approach, we calculated the consequences of an assisted migration project across a very large combination of translocated species and recipient ecosystems. We predicted the probability of a successful assisted migration and the number of local extinctions would result from establishment of the translocated species. Using an ensemble of 1.5×106 simulated 15‐species recipient ecosystems, we estimated that translocated species will successfully establish in 83% of cases if introduced to stable, high‐quality habitats. However, assisted migration projects were estimated to cause an average of 0.6 extinctions and 5% of successful translocations triggered 4 or more local extinctions. Quantifying the impacts to species within recipient ecosystems is critical to help managers weigh the benefits and negative consequences of assisted migration. Article Impact Statement: Assisted migration is controversial conservation initiative because its effects on recipient ecosystems are not easily predicted. [ABSTRACT FROM AUTHOR]

Native biodiversity is threatened by invasive species in many terrestrial and marine systems, and conservation managers have demonstrated successes by responding with eradication or control programs. Although invasive species are often the direct cause of threat to native species, ecosystems can react in unexpected ways to their removal or reduction. Here, we use theoretical models to predict boom‐bust dynamics, where the removal of predatory or competitive pressure from a native herbivore results in oscillatory population dynamics (boom‐bust), which can endanger the native species' population in the short term. We simulate control activities, applied to multiple theoretical three‐species Lotka‐Volterra ecosystem models consisting of vegetation, a native herbivore, and an invasive predator. Based on these communities, we then develop a predictive tool that—based on relative parameter values—predicts whether control efforts directed at the invasive predator will lead to herbivore release followed by a crash. Further, by investigating the different functional responses, we show that model structure, as well as model parameters, are important determinants of conservation outcomes. Finally, control strategies that can mitigate these negative consequences are identified. Managers working in similar data‐poor ecosystems can use the predictive tool to assess the probability that their system will exhibit boom‐bust dynamics, without knowing exact community parameter values. [ABSTRACT FROM AUTHOR]

The eradication of invasive species from islands is an important part of managing these ecologically unique and at‐risk regions. Island eradications are complex projects and mathematical models play an important role in supporting efficient and transparent decision‐making. In this review, we cover the past applications of modeling to island eradications, which range from large‐scale prioritizations across groups of islands, to project‐level decision‐making tools. While quantitative models have been formulated and parameterized for a range of important problems, there are also critical research gaps. Many applications of quantitative modeling lack uncertainty analyses, and are therefore overconfident. Forecasting the ecosystem‐wide impacts of species eradications is still extremely challenging, despite recent progress in the field. Overall, the field of quantitative modeling is well‐developed for island eradication planning. Multiple practical modeling tools are available for, and are being applied to, a diverse suite of important decisions, and quantitative modeling is well placed to address pressing issues in the field. [ABSTRACT FROM AUTHOR]

The age or size structure of a population has a marked influence on its demography and reproductive capacity. While declines in coral cover are well documented, concomitant shifts in the size-frequency distribution of coral colonies are rarely measured at large spatial scales. Here, we document major shifts in the colony size structure of coral populations along the 2300 km length of the Great Barrier Reef relative to historical baselines (1995/1996). Coral colony abundances on reef crests and slopes have declined sharply across all colony size classes and in all coral taxa compared to historical baselines. Declines were particularly pronounced in the northern and central regions of the Great Barrier Reef, following mass coral bleaching in 2016 and 2017. The relative abundances of large colonies remained relatively stable, but this apparent stability masks steep declines in absolute abundance. The potential for recovery of older fecund corals is uncertain given the increasing frequency and intensity of disturbance events. The systematic decline in smaller colonies across regions, habitats and taxa, suggests that a decline in recruitment has further eroded the recovery potential and resilience of coral populations. [ABSTRACT FROM AUTHOR]

Well-managed and enforced no-take marine reserves generate important larval subsidies to neighboring habitats and thereby contribute to the long-term sustainability of fisheries. However, larval dispersal patterns are variable, which leads to temporal fluctuations in the contribution of a single reserve to the replenishment of local populations. Identifying management strategies that mitigate the uncertainty in larval supply will help ensure the stability of recruitment dynamics and minimize the volatility in fishery catches. Here, we use genetic parentage analysis to show extreme variability in both the dispersal patterns and recruitment contribution of four individual marine reserves across six discrete recruitment cohorts for coral grouper (Plectropomus maculatus) on the Great Barrier Reef. Together, however, the asynchronous contributions from multiple reserves create temporal stability in recruitment via a connectivity portfolio effect. This dampening effect reduces the variability in larval supply from individual reserves by a factor of 1.8, which effectively halves the uncertainty in the recruitment contribution of individual reserves. Thus, not only does the network of four marine reserves generate valuable larval subsidies to neighboring habitats, the aggregate effect of individual reserves mitigates temporal fluctuations in dispersal patterns and the replenishment of local populations. Our results indicate that small networks of marine reserves yield previously unrecognized stabilizing benefits that ensure a consistent larval supply to replenish exploited fish stocks. [ABSTRACT FROM AUTHOR]

Species and ecosystems usually face more than one threat. The damage caused by these multiple threats can accumulate nonlinearly: either subadditively, when the joint damage of combined threats is less than the damages of both threats individually added together, or superadditively, when the joint damage is greater than the two individual damages added together. These additivity dynamics are commonly attributed to the nature of the threatening processes, but conflicting empirical observations challenge this assumption. Here, we use a theoretical model to demonstrate that the additivity of threats can change with different magnitudes of threat impacts (effect of a threat on the population parameter, like growth rate). We use a harvested single-species population model to integrate the effects of multiple threats on equilibrium abundance. Our results reveal that threats do not always display consistent additive behavior, even in simple systems. Instead, their additivity depends on the magnitudes of the impacts of two threats, and the population parameter that is impacted by each threat. In our model specifically, when multiple threats have a low impact on the growth rate of a population, they display superadditive dynamics. In contrast, threats that impact the species’ carrying capacity are always additive or subadditive. These dynamics can be understood by reference to the curvature of the relationship between a given population parameter (e.g., growth) and equilibrium population size. Our results suggest that management actions can achieve amplified benefits if they target low-amplitude threats that affect the growth rate, since these will be in a superadditive phase. More generally, our results suggest that cumulative impact theory should focus more than previously on the magnitude of the impact on the population parameter, and should be cautious about attributing additive dynamics to particular threat combinations. [ABSTRACT FROM AUTHOR]

Larval dispersal is a critically important yet enigmatic process in marine ecology, evolution, and conservation. Determining the distance and direction that tiny larvae travel in the open ocean continues to be a challenge. Our current understanding of larval dispersal patterns at management-relevant scales is principally and separately informed by genetic parentage data and biological-oceanographic (biophysical) models. Parentage datasets provide clear evidence of individual larval dispersal events, but their findings are spatially and temporally limited. Biophysical models offer a more complete picture of dispersal patterns at regional scales but are of uncertain accuracy. Here, we develop statistical techniques that integrate these two important sources of information on larval dispersal. We then apply these methods to an extensive genetic parentage dataset to successfully validate a high-resolution biophysical model for the economically important reef fish species Plectropomus maculatus in the southern Great Barrier Reef. Our results demonstrate that biophysical models can provide accurate descriptions of larval dispersal at spatial and temporal scales that are relevant to management. They also show that genetic parentage datasets provide enough statistical power to exclude poor biophysical models. Biophysical models that included species-specific larval behaviour provided markedly better fits to the parentage data than assuming passive behaviour, but incorrect behavioural assumptions led to worse predictions than ignoring behaviour altogether. Our approach capitalises on the complementary strengths of genetic parentage datasets and high-resolution biophysical models to produce an accurate picture of larval dispersal patterns at regional scales. The results provide essential empirical support for the use of accurately parameterised biophysical larval dispersal models in marine spatial planning and management. [ABSTRACT FROM AUTHOR]

Presents a study which observed long-range order of the copper plutonium type in the I-III-VI[sub2] material copper indium selenide. Methods; Results; Discussion.

Introduction Rivaroxaban selectively inhibits factor Xa (FXa), which plays a central role in blood coagulation. In addition, FXa activates protease-activated receptor-2 (PAR-2). We have shown that PAR-2 −/− mice exhibit less cardiac dysfunction after cardiac injury. Material and methods Wild-type (WT) and PAR-2 −/− mice were subjected to left anterior descending artery (LAD) ligation to induce cardiac injury and heart failure. Mice received either placebo or rivaroxaban chow either starting at the time of surgery or 3 days after surgery and continued up to 28 days. Cardiac function was measured by echocardiography pre-surgery and 3, 7 and 28 days after LAD ligation. We also measured anticoagulation, intravascular thrombi, infarct size, cardiac hypertrophy and inflammation at various times. Results Rivaroxaban increased the prothrombin time and inhibited the formation of intravascular thrombi in mice subjected to LAD ligation. WT mice receiving rivaroxaban immediately after surgery had similar infarct sizes at day 1 as controls but exhibited significantly less impairment of cardiac function at day 3 and beyond compared to the placebo group. Rivaroxaban also inhibited the expansion of the infarct at day 28. Rivaroxaban did not significantly affect the expression of inflammatory mediators or a neutrophil marker at day 2 after LAD ligation. Delaying the start of rivaroxaban administration until 3 days after surgery failed to preserve cardiac function. In addition, rivaroxaban did not reduce cardiac dysfunction in PAR-2 −/− mice. Conclusions Early administration of rivaroxaban preserves cardiac function in mice after LAD ligation. [ABSTRACT FROM AUTHOR]

Abstract: Marine protected areas (MPAs) are increasingly integrated into fishery management for coastal systems. Size and spacing rules (SSRs) have been proposed as simple MPA design guidelines, especially in regions where population connectivity data are limited. We assessed whether SSRs allow managers to design effective MPA networks under spatiotemporally varying dispersal patterns using a spatially realistic population model parameterized for a commercially‐exploited fish species on the Great Barrier Reef. SSRs are used to design MPA networks, and population simulations are used to measure the mean and variance of the resulting population size and fishery catch. We show that SSR performance is contingent on the extent of the MPA network, and whether species’ connectivity data can be used to target areas for protection. For example, in the absence of connectivity data, a “many small” MPAs rule provides the least variable management outcome. Synthesis and applications. We demonstrate that the performance and usefulness of size and spacing rules (SSRs) as guidelines for marine protected areas (MPAs) depend on the level of knowledge about larval dispersal, as well as the level of current exploitation in the fishery. These context‐dependent results offer particularly relevant guidance to future MPA design projects in regions with limited connectivity data. [ABSTRACT FROM AUTHOR]

The Late Chalcolithic (4400–3950b.c.) occupation levels from Ovçular Tepesi have yielded a significant assemblage of copper objects and remains of copper production. Together with ore finds, two fragments of nozzle,crucible remains, and a number of small metal artifacts, this assemblage includes the unexpected discovery of three copper axes in an infant burial jar. These axes are the earliest examples of large copper tools known to date in southwestern Asia, whether it is in the Caucasus, Iran, or the Anatolian highlands. More importantly, the fact that these objects were locally produced suggests that significant metallurgical activities were being carried out at Ovçular as early as the second half of the 5th millenniumb.c. After presenting the evidence from Ovçular Tepesi, this paper will proceed to a reassessment of the available archaeological and geochemical data concerning the emergence of extractive metallurgy in the southern Caucasus. [ABSTRACT FROM AUTHOR]

Coastal marine ecosystems can be managed by actions undertaken both on the land and in the ocean. Quantifying and comparing the costs and benefits of actions in both realms is therefore necessary for efficient management. Here, we quantify the link between terrestrial sediment runoff and a downstream coastal marine ecosystem and contrast the cost-effectiveness of marine- and land-based conservation actions. We use a dynamic land- and sea-scape model to determine whether limited funds should be directed to 1 of 4 alternative conservation actions—protection on land, protection in the ocean, restoration on land, or restoration in the ocean—to maximise the extent of light-dependent marine benthic habitats across decadal timescales. We apply the model to a case study for a seagrass meadow in Australia. We find that marine restoration is the most cost-effective action over decadal timescales in this system, based on a conservative estimate of the rate at which seagrass can expand into a new habitat. The optimal decision will vary in different social–ecological contexts, but some basic information can guide optimal investments to counteract land- and ocean-based stressors: (1) marine restoration should be prioritised if the rates of marine ecosystem decline and expansion are similar and low; (2) marine protection should take precedence if the rate of marine ecosystem decline is high or if the adjacent catchment is relatively intact and has a low rate of vegetation decline; (3) land-based actions are optimal when the ratio of marine ecosystem expansion to decline is greater than 1:1.4, with terrestrial restoration typically the most cost-effective action; and (4) land protection should be prioritised if the catchment is relatively intact but the rate of vegetation decline is high. These rules of thumb illustrate how cost-effective conservation outcomes for connected land–ocean systems can proceed without complex modelling. [ABSTRACT FROM AUTHOR]

To counteract global species decline, modern biodiversity conservation engages in large projects, spends billions of dollars, and includes many organizations working simultaneously within regions. To add to this complexity, the conservation sector has hierarchical structure, where conservation actions are often outsourced by funders (foundations, government, etc.) to local organizations that work on-the-ground. In contrast, conservation science usually assumes that a single organization makes resource allocation decisions. This discrepancy calls for theory to understand how the expected biodiversity outcomes change when interactions between organizations are accounted for. Here, we used a game theoretic model to explore how biodiversity outcomes are affected by vertical and horizontal interactions between 3 conservation organizations: a funder that outsourced its actions and 2 local conservation organizations that work on-the-ground. Interactions between the organizations changed the spending decisions made by individual organizations, and thereby the magnitude and direction of the conservation benefits. We showed that funders would struggle to incentivize recipient organizations with set priorities to perform desired actions, even when they control substantial amounts of the funding and employ common contracting approaches to enhance outcomes. Instead, biodiversity outcomes depended on priority alignment across the organizations. Conservation outcomes for the funder were improved by strategic interactions when organizational priorities were well aligned, but decreased when priorities were misaligned. Meanwhile, local organizations had improved outcomes regardless of alignment due to additional funding in the system. Given that conservation often involves the aggregate actions of multiple organizations with different objectives, strategic interactions between organizations need to be considered if we are to predict possible outcomes of conservation programs or costs of achieving conservation targets. [ABSTRACT FROM AUTHOR]

Introduction Mice with a complete absence of tissue factor (TF) die during embryonic development whereas mice with low levels of TF (Low-TF mice) survive to adulthood. Low-TF mice exhibit spontaneous hemorrhage in various organs, including the lung. In contrast, mice can survive without protease-activated receptor (PAR)-4, which is the major thrombin receptor on mouse platelets. We determined the effect of combining a deficiency PAR-4 (primary hemostasis) with a deficiency in TF (secondary hemostasis) on embryonic development and survival of adult mice. Materials and methods Low-TF mice (mTF −/− , hTF +/+ ) were crossed with PAR-4 −/− mice to generate heterozygous mice (mTF +/− , hTF +/− , PAR-4 +/− ). These mice were intercrossed to generate Low-TF mice lacking PAR-4. Mice surviving to wean were genotyped and survival was monitored for 6 months. Results We observed the expected number of Low-TF,PAR-4 −/− mice at wean indicating survival in utero and after birth. However, an absence of PAR-4 was associated with premature death of all Low-TF,PAR-4 −/− mice in the 6 month observational period. This compares with 40% death of the Low-TF,PAR-4 +/+ mice (p = 0.003). Low-TF,PAR-4 +/− mice had an intermediate phenotype with 55% of the mice dying within 6 months. The primary cause of mortality of Low-TF,PAR-4 −/− mice was pulmonary hemorrhage. Conclusions Low-TF,PAR-4 −/− mice survive into adulthood, but combining a deficiency of primary hemostasis (PAR-4 deficiency) with secondary hemostasis (low levels of TF) leads to premature death primarily due to pulmonary hemorrhage. [ABSTRACT FROM AUTHOR]

Marine reserve networks must ensure the representation of important conservation features, and also guarantee the persistence of key populations. For many species, designing reserve networks is complicated by the absence or limited availability of spatial and life-history data. This is particularly true for data on larval dispersal, which has only recently become available. However, systematic conservation planning methods currently incorporate demographic processes through unsatisfactory surrogates. There are therefore two key challenges to designing marine reserve networks that achieve feature representation and demographic persistence constraints. First, constructing a method that efficiently incorporates persistence as well as complementary feature representation. Second, incorporating persistence using a mechanistic description of population viability, rather than a proxy such as size or distance. Here we construct a novel systematic conservation planning method that addresses both challenges, and parameterise it to design a hypothetical marine reserve network for fringing coral reefs in the Keppel Islands, Great Barrier Reef, Australia. For this application, we describe how demographic persistence goals can be constructed for an important reef fish species in the region, the bar-cheeked trout (Plectropomus maculatus). We compare reserve networks that are optimally designed for either feature representation or demographic persistence, with a reserve network that achieves both goals simultaneously. As well as being practically applicable, our analyses also provide general insights into marine reserve planning for both representation and demographic persistence. First, persistence constraints for dispersive organisms are likely to be much harder to achieve than representation targets, due to their greater complexity. Second, persistence and representation constraints pull the reserve network design process in divergent directions, making it difficult to efficiently achieve both constraints. Although our method can be readily applied to the data-rich Keppel Islands case study, we finally consider the factors that limit the method’s utility in information-poor contexts common in marine conservation. [ABSTRACT FROM AUTHOR]

Management strategies to reduce the risks to human life and property from wildfire commonly involve burning native vegetation. However, planned burning can conflict with other societal objectives such as human health and biodiversity conservation. These conflicts are likely to intensify as fire regimes change under future climates and as growing human populations encroach farther into fire-prone ecosystems. Decisions about managing fire risks are therefore complex and warrant more sophisticated approaches than are typically used. We applied a multicriteria decision making approach (MCDA) with the potential to improve fire management outcomes to the case of a highly populated, biodiverse, and flammable wildland-urban interface. We considered the effects of 22 planned burning options on 8 objectives: house protection, maximizing water quality, minimizing carbon emissions and impacts on human health, and minimizing declines of 5 distinct species types. The MCDA identified a small number of management options (burning forest adjacent to houses) that performed well for most objectives, but not for one species type (arboreal mammal) or for water quality. Although MCDA made the conflict between objectives explicit, resolution of the problem depended on the weighting assigned to each objective. Additive weighting of criteria traded off the arboreal mammal and water quality objectives for other objectives. Multiplicative weighting identified scenarios that avoided poor outcomes for any objective, which is important for avoiding potentially irreversible biodiversity losses. To distinguish reliably among management options, future work should focus on reducing uncertainty in outcomes across a range of objectives. Considering management actions that have more predictable outcomes than landscape fuel management will be important. We found that, where data were adequate, an MCDA can support decision making in the complex and often conflicted area of fire management. [ABSTRACT FROM AUTHOR]

Protected area networks are designed to restrict anthropogenic pressures in areas of high biodiversity. Resource users respond by seeking to replace some or all of the lost resources from locations elsewhere in the landscape. Protected area networks thereby perturb the pattern of human pressures by displacing extractive effort from within protected areas into the broader landscape, a process known as leakage. The negative effects of leakage on conservation outcomes have been empirically documented and modeled using homogeneous descriptions of conservation landscapes. Human resource use and biodiversity vary greatly in space, however, and a theory of leakage must describe how this heterogeneity affects the magnitude, pattern, and biodiversity impacts of leakage. We combined models of household utility, adaptive human foraging, and biodiversity conservation to provide a bioeconomic model of leakage that accounts for spatial heterogeneity. Leakage had strong and divergent impacts on the performance of protected area networks, undermining biodiversity benefits but mitigating the negative impacts on local resource users. When leakage was present, our model showed that poorly designed protected area networks resulted in a substantial net loss of biodiversity. However, the effects of leakage can be mitigated if they are incorporated ex-ante into the conservation planning process. If protected areas are coupled with nonreserve policy instruments such as market subsidies, our model shows that the trade-offs between biodiversity and human well-being can be further and more directly reduced. [ABSTRACT FROM AUTHOR]

Islands are global hotspots of both biodiversity and extinction. Invasive species are a primary threat, and the majority of islands have been invaded by more than one. Multispecies eradications are essential for conserving the biodiversity of these islands, but experience has shown that eradicating species at the wrong time can be disastrous for endemic species., Managers not only have to decide how to eradicate each invasive species, they need to determine when to target each species, and how to control multiple species with a limited budget. We use dynamic control theory to show that, when resources are limited, species should be eradicated in a particular order (an eradication schedule). We focus on a common invaded island ecosystem motif, where one invasive predator consumes two prey species (one endemic, one invasive), and managers wish to eradicate both invasives while ensuring the persistence of the endemic species. We identify the optimal eradication schedule for this entire class of problem. To illustrate the application of our solution, we also analyse a particular case study from California's Channel Islands., For any island ecosystem that shares this motif, managers should begin by allocating all of their resources towards invasive predator control. Only later should resources be shifted towards controlling the invasive prey. This shift should ideally be gradual, but an abrupt shift is very close to optimal. The Channel Islands case study confirms these findings. Targeting both species simultaneously is substantially suboptimal., We reach the robust conclusion that the same eradication schedule should be applied to any island with this ecosystem motif, even if the ecosystem contains different species to the Channel Islands case study., Synthesis and applications. Although very numerous, the world's invaded island ecosystems could be described by a limited range of invaded ecosystem motifs. By calculating robust optimal eradication schedules for each motif, the approach defined in this study could offer rapid decision-support for a large number of future conservation projects where specific data are scarce. [ABSTRACT FROM AUTHOR]

When protected areas reduce threats within their boundaries, they often displace a portion of these threats into adjacent areas through a process known as ‘leakage’, undermining conservation objectives. Using theoretical models and a case study of terrestrial mammals in Indonesia, we develop the first theoretical explanation of how leakage impacts conservation actions, and highlight conservation strategies that mitigate these impacts. Although leakage is a socio-economic process, we demonstrate that its negative impacts are also affected by the distribution of species, with leakage having larger impacts in landscapes with homogeneous distribution of species richness. Moreover, leakage has a greater negative effect when conservation strategies are implemented opportunistically, even creating the potential for perversely negative consequences from protected area establishment. Leakage thereby increases the relative benefits of systematic conservation planning over opportunism, especially in areas with high leakage and heterogeneously distributed species. Although leakage has the potential to undermine conservation actions, conservation planning can minimize this risk. [ABSTRACT FROM AUTHOR]

Conservation outcomes are principally achieved through the protection of intact habitat or the restoration of degraded habitat. Restoration is generally considered a lower priority action than protection because protection is thought to provide superior outcomes, at lower costs, without the time delay required for restoration. Yet while it is broadly accepted that protected intact habitat safeguards more biodiversity and generates greater ecosystem services per unit area than restored habitat, conservation lacks a theory that can coherently compare the relative outcomes of the two actions. We use a dynamic landscape model to integrate these two actions into a unified conservation theory of protection and restoration. Using nonlinear benefit functions, we show that both actions are crucial components of a conservation strategy that seeks to optimise either biodiversity conservation or ecosystem services provision. In contrast to conservation orthodoxy, in some circumstances, restoration should be strongly preferred to protection. The relative priority of protection and restoration depends on their costs and also on the different time lags that are inherent to both protection and restoration. We derive a simple and easy-to-interpret heuristic that integrates these factors into a single equation that applies equally to biodiversity conservation and ecosystem service objectives. We use two examples to illustrate the theory: bird conservation in tropical rainforests and coastal defence provided by mangrove forests. [ABSTRACT FROM AUTHOR]

Tissue factor (TF) is the primary activator of the coagulation cascade. Under normal conditions, endothelial cells (ECs) and blood cells, such as monocytes, do not express TF. However, bacterial lipopolysaccharide (LPS) induces TF expression in monocytes and this leads to disseminated intravascular coagulation during endotoxemia and sepsis. A variety of stimuli induce TF expression in ECs in vitro, although it is unclear how much TF is expressed by the endothelium in vivo. LPS induction of TF gene expression in monocytic cells and ECs is mediated by various intracellular signaling pathways and the transcription factors NF-κB, AP-1 and Egr-1. In contrast, vascular endothelial cell growth factor (VEGF) induces TF gene expression in ECs via the transcription factors NFAT and Egr-1. Similarly, oxidized phospholipids (such as 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphorylcholine) induce TF expression in ECs and possibly monocytes via NFAT and Egr-1. Thromboxane A2 (TXA2) can now be added to the list of stimuli that induce TF gene expression in both monocytes and ECs. Interestingly, inhibition of the TX-prostanoid (TP) receptor also reduces TF expression in with tumor necrosis factor (TNF)-α stimulated ECs and LPS stimulated monocytes, which suggests that TP receptor antagonist may be useful in reducing pathologic TF expression in the vasculature and blood. [ABSTRACT FROM AUTHOR]

Traditionally, physiologists have estimated the ability of organisms to withstand lower partial pressures of oxygen by estimating the partial pressure at which oxygen consumption begins to decrease (known as the critical PO2 or Pc). For almost 30years, the principal way in which Pc has been estimated has been via piecewise 'broken stick' regression (BSR). BSR was a useful approach when more sophisticated analyses were less available, but BSR makes a number of unsupported assumptions about the underlying form of the relationship between the rate of oxygen consumption and oxygen availability. The BSR approach also distils a range of values into a single point with no estimate of error. In accordance with more general calls to fit functions to continuous data, we propose the use of nonlinear regression (NLR) to fit various curvilinear functions to oxygen consumption data in order to estimate Pc. Importantly, our approach is back-compatible so that estimates using traditional methods in earlier studies can be compared with data estimates from our technique. When we compared the performance of our approach relative to the traditional BSR approach for real world and simulated data, we found that under realistic circumstances, NLR was more accurate and provided more powerful hypothesis tests. We recommend that future studies make use of NLR to estimate Pc, and also suggest that this approach might be more appropriate for a range of physiological studies that use BSR currently. [ABSTRACT FROM AUTHOR]

Much of the theory on offspring size focuses on the effects of habitat quality on the relationship between offspring size and fitness. Habitat spacing may be another important factor that affects selection on offspring size when offspring disperse prior to colonization and accrue deferred costs that are mediated by offspring size., We developed a theoretical model, based on a well-known optimality model, of how selection on offspring size changes with dispersal distance. The model assumes that offspring fitness depends on both offspring size and dispersal duration and that dispersal time and distance are positively related. Such assumptions are based on thousands of marine invertebrate species with non-feeding larvae, but our model also applies more generally to any organism where offspring size modifies the energetic costs of dispersal, and there is a positive relationship between dispersal duration and distance., Our model predicts that, even when habitat quality does not vary, more isolated habitats may favour the production of fewer, larger offspring if smaller offspring incur greater deferred costs of dispersal. We then empirically demonstrate that offspring size and dispersal duration have interactive effects on post-settlement survival in a marine invertebrate ( Bugula neritina), and such size-dependent deferred costs of dispersal are of a magnitude sufficient enough to potentially favour larger offspring in isolated habitats., Together, our results indicate that the spatial pattern of suitable habitat could impose very different selective regimes on offspring size compared with the effects of habitat quality. Furthermore, our predictions contrast to those predicted for seed size and dispersal in plants, where the production of smaller, more numerous seeds is often a more efficient way for mothers to access distant, suitable habitat. [ABSTRACT FROM AUTHOR]

Although ecological assemblages frequently depart from neutral model predictions, these discrepancies have not been unambiguously attributed to neutral theory's core assumption: that community structure is primarily the result of chance variation in birth, death, speciation, and dispersal, rather than the manifestation of demographic differences among species. Using coral communities in Barbados from four time periods during the Pleistocene, we demonstrate that the neutral theory cannot explain coral community similarity distributions, species' regional abundance distributions, or their local occupancy. Furthermore, discrepancies between the neutral theory and the observed communities can be attributed to violation of the core assumption of species equivalence. In particular, species' variable growth rates are driving departures from neutral predictions. Our results reinforce an understanding of reef coral community assembly that invokes trade-offs in species' demographic strategies. The results further suggest that conservation management actions will fail if they are based on the neutral assumption that different coral species are equally able to create live coral cover in the shallow-water reef environment. These findings highlight the importance of developing biodiversity theory that can parsimoniously incorporate species differences in coral reef communities, rather than further elaborating neutral theory. [ABSTRACT FROM AUTHOR]

Malleefowl Leipoa ocellata populations across Australia are declining and the range of the species is contracting. Despite a century of research much uncertainty remains about which factors are driving this decline. Consequently, it is also unclear which conservation actions will reduce the species’ extinction risk. In particular, we lack a quantitative understanding of malleefowl population dynamics. Here we use estimates derived from the literature to provide the first parametrization of a population viability analysis (PVA) for malleefowl. This model creates a quantitative framework for synthesizing existing information and comparing potential management strategies, and will help guide research activities by identifying critical aspects of the malleefowl’s life history. We model population dynamics as stochastic events that depend on individual characteristics, weather conditions and local management actions. Our PVA indicates that an isolated population of 32 adult birds would almost certainly decline to extinction over a 20-year period. Translocating and releasing captive-bred juveniles slows this rate of decline and intensively baiting for foxes can reverse it. Adult mortality rates have the greatest influence on population viability, and land managers should therefore prioritize conservation actions that target adult survivorship over actions that benefit earlier life stages. Quantitative research on the malleefowl should focus on the demographics of the adult life stage, their dispersal and the impacts of fire and grazing. Our analysis highlights the role of PVA models in assessing the cost-effectiveness of alternative management actions, and framing future research priorities for threatened species. [ABSTRACT FROM PUBLISHER]

The coexistence of multiple species on a smaller number of limiting resources is an enduring ecological paradox. The mechanisms that maintain such biodiversity are of great interest to ecology and of central importance to conservation. We describe and prove a unique and robust mechanism for coexistence: Species that differ only in their dispersal abilities can coexist, if habitat patches are distributed at irregular distances. This mechanism is straightforward and ecologically intuitive, but can nevertheless create complex coexistence patterns that are robust to substantial environmental stochasticity. The Great Barrier Reef (GBR) is noted for its diversity of reef fish species and its complex arrangement of reef habitat. We demonstrate that this mechanism can allow fish species with different pelagic larval durations to stably coexist in the GBR. Further, coexisting species on the GBR often dominate different subregions, defined primarily by cross-shelf position. Interspecific differences in dispersal ability generate similar coexistence patterns when dispersal is influenced by larval behavior and variable oceanographic conditions. Many marine and terrestrial ecosystems are characterized by patchy habitat distributions and contain coexisting species that have different dispersal abilities. This coexistence mechanism is therefore likely to have ecological relevance beyond reef fish. [ABSTRACT FROM AUTHOR]

During vascular development, endothelial cells are exposed to a variety of rapidly changing factors, including fluctuating oxygen levels. We have previously shown that ankyrin repeat and suppressor of cytokine signalling box protein 4 (ASB4) is the most highly differentially expressed gene in the vascular lineage during early differentiation and is expressed in the embryonic vasculature at a time when oxygen tension is rising because of the onset of placental blood flow. To further our understanding of the regulation of ASB4 expression in endothelial cells, we tested the effect of various stressors for their ability to alter ASB4 expression in the immortalized murine endothelial cell lines MS1 and SVR. ASB4 expression is decreased during hypoxic insult and shear stress, whereas it is increased in response to tumour necrosis factor alpha (TNF- α). Further investigation indicated that nuclear factor kappa B (NF- κB) is the responsible transcription factor involved in the TNF- α-induced upregulation of ASB4, placing ASB4 downstream of NF- κB in the TNF- α signalling cascade and identifying it as a potential regulator for TNF- α's numerous functions associated with inflammation, angiogenesis and apoptosis. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

There has been a dramatic increase in the number of conservation organizations worldwide. It is now common for multiple organizations to operate in the same landscape in pursuit of different conservation goals. New objectives, such as maintenance of ecosystem services, will attract additional funding and new organizations to conservation. Systematic conservation planning helps in the design of spatially explicit management actions that optimally conserve multiple landscape features (e.g., species, ecosystems, or ecosystem services). But the methods used in its application implicitly assume that a single actor implements the optimal plan. We investigated how organizational behavior and conservation outcomes are affected by the presence of autonomous implementing organizations with different objectives. We used simulation models and game theory to explore how alternative behaviors (e.g., organizations acting independently or explicitly cooperating) affected an organization's ability to protect their feature of interest, and investigated how the distribution of features in the landscape influenced organizations' attitudes toward cooperation. Features with highly correlated spatial distributions, although typically considered an opportunity for mutually beneficial conservation planning, can lead to organizational interactions that result in lower levels of protection. These detrimental outcomes can be avoided by organizations that cooperate when acquiring land. Nevertheless, for cooperative purchases to benefit both organizations' objectives, each must forgo the protection of land parcels that they would consider to be of high conservation value. Transaction costs incurred during cooperation and the sources of conservation funding could facilitate or hinder cooperative behavior. [ABSTRACT FROM AUTHOR]

Barriers are used to achieve diverse objectives in conservation and biosecurity. In conservation management, fences are often erected to exclude introduced predators and to contain diseased animals or invasive species. Planning an efficient conservation fence involves a number of decisions, including the size and design of the enclosure. We formulated the first general framework for building a fence that minimizes long-term management costs by balancing the expense of constructing a more secure barrier against the costs of coping with more frequent failures. The approach systematically considers the range of potential solutions to a well-defined fencing problem and results in a solution that maximizes conservation return on investment. We illustrated this method by designing efficient fences to address two different conservation goals: exclusion of invasive predators from populations of threatened eastern barred bandicoots (Perameles gunnii ) and maintenance of isolated populations of healthy Tasmanian devils (Sarcophilus harrisii ). A systematic approach to conservation fencing allows the best fence design to be chosen quantitatively and defensibly. It also facilitates conservation decisions at a strategic level by allowing fencing to be compared transparently with alternative conservation management actions. [ABSTRACT FROM AUTHOR]

Marine Protected Areas are usually static, permanently closed areas. There are, however, both social and ecological reasons to adopt dynamic closures, where reserves move through time. Using a general theoretical framework, we investigate whether dynamic closures can improve the mean biomass of herbivorous fishes on reef systems, thereby enhancing resilience to undesirable phase-shifts. At current levels of reservation (10–30%), moving protection between all reefs in a system is unlikely to improve herbivore biomass, but can lead to a more even distribution of biomass. However, if protected areas are rotated among an appropriate subset of the entire reef system (e.g. rotating 10 protected areas between only 20 reefs in a 100 reef system), dynamic closures always lead to increased mean herbivore biomass. The management strategy that will achieve the highest mean herbivore biomass depends on both the trajectories and rates of population recovery and decline. Given the current large-scale threats to coral reefs, the ability of dynamic marine protected areas to achieve conservation goals deserves more attention. [ABSTRACT FROM AUTHOR]

Conservation management actions and decisions are often defined by the location of ecological boundaries, for example, the present range of invasive or threatened species. The position of these boundaries can be cryptic, and managers must therefore directly sample sites, an expensive and time-consuming process. While accurate boundary location techniques have been considered by ecological theorists, the issue of cost-effective, or optimal boundary location has not. We propose a general framework for boundary location which incorporates both cost-efficiency and uncertainty. To illustrate its application, we use it to help locate an infectious disease front in the endangered Tasmanian devil population. The method ensures optimal spatial sampling by maximizing the expected information gained from each sample. When resources are limited, our method provides more accurate estimates of the boundary location than traditional sampling protocols. Using a formal decision theory sampling design encourages economically efficient actions, and provides defensible and transparent rationale for management actions. [Copyright &y& Elsevier]

Land acquisition is a common approach to biodiversity conservation but is typically subject to property availability on the public market. Consequently, conservation plans are often unable to be implemented as intended. When properties come on the market, conservation agencies must make a choice: purchase immediately, often without a detailed knowledge of its biodiversity value; survey the parcel and accept the risk that it may be removed from the market during this process; or not purchase and hope a better parcel comes on the market at a later date. We describe both an optimal method, using stochastic dynamic programming, and a simple rule of thumb for making such decisions. The solutions to this problem illustrate how optimal conservation is necessarily dynamic and requires explicit consideration of both the time period allowed for implementation and the availability of properties. [ABSTRACT FROM AUTHOR]

The optimal allocation of conservation resources between biodiverse conservation regions has generally been calculated using stochastic dynamic programming, or using myopic heuristics. These solutions are hard to interpret and may not be optimal. To overcome these two limitations, this paper approaches the optimal conservation resource allocation problem using optimal control theory. A solution using Pontryagin's maximum principle provides novel insight into the general properties of efficient conservation resource allocation strategies, and allows more extensive testing of the performance of myopic heuristics. We confirmed that a proposed heuristic (minimize short-term loss) yields near-optimal results in complex allocation situations, and found that a qualitative allocation feature observed in previous analyses (bang-bang allocation) is a general property of the optimal allocation strategy. [ABSTRACT FROM AUTHOR]

Abstract: Almost all metapopulation modelling assumes that connectivity between patches is only a function of distance, and is therefore symmetric. However, connectivity will not depend only on the distance between the patches, as some paths are easy to traverse, while others are difficult. When colonising organisms interact with the heterogeneous landscape between patches, connectivity patterns will invariably be asymmetric. There have been few attempts to theoretically assess the effects of asymmetric connectivity patterns on the dynamics of metapopulations. In this paper, we use the framework of complex networks to investigate whether metapopulation dynamics can be determined by directly analysing the asymmetric connectivity patterns that link the patches. Our analyses focus on “patch occupancy” metapopulation models, which only consider whether a patch is occupied or not. We propose three easily calculated network metrics: the “asymmetry” and “average path strength” of the connectivity pattern, and the “centrality” of each patch. Together, these metrics can be used to predict the length of time a metapopulation is expected to persist, and the relative contribution of each patch to a metapopulation''s viability. Our results clearly demonstrate the negative effect that asymmetry has on metapopulation persistence. Complex network analyses represent a useful new tool for understanding the dynamics of species existing in fragmented landscapes, particularly those existing in large metapopulations. [Copyright &y& Elsevier]

Priorities for conservation investment at a global scale that are based on a single taxon have been criticized because geographic richness patterns vary taxonomically. However, these concerns focused only on biodiversity patterns and did not consider the importance of socioeconomic factors, which must also be included if conservation funding is to be allocated efficiently. In this article, we create efficient global funding schedules that use information about conservation costs, predicted habitat loss rates, and the endemicity of seven different taxonomic groups. We discover that these funding allocation schedules are less sensitive to variation in taxon assessed than to variation in cost and threat. Two-thirds of funding is allocated to the same regions regardless of the taxon. compared with only one-fifth if threat and cost are not included in allocation decisions. Hence, if socioeconomic factors are considered, we can be more confident about global-scale decisions guided by single taxonomic groups. [ABSTRACT FROM AUTHOR]

Our view of sperm competition is largely shaped by game-theoretic models based on external fertilizers. External fertilization is of particular interest as it is the ancestral mode of reproduction and as such, relevant to the evolution and maintenance of anisogamy (i.e., large eggs and tiny, numerous sperm). Current game-theoretic models have been invaluable in generating predictions of male responses to sperm competition in a range of internal fertilizers but these models are less relevant to marine broadcast spawners, the most common and archetypal external fertilizers. Broadcast spawners typically have incomplete fertilization due to sperm limitation and/or polyspermy (too many sperm), but the effects of incomplete (<100% fertilization rates) fertilization on game-theoretic predictions are unclear particular with regards to polyspermy. We show that incorporating the effects of sperm concentration on fertilization success changes the predictions of a classic game-theoretic model, dramatically reversing the relationship between sperm competition and the evolutionarily stable sperm release strategy. Furthermore, our results suggest that male and female broadcast spawners are likely to be in conflict at both ends of the sperm environment continuum rather than only in conditions of excess sperm as previously thought. Across the majority of the parameter space we explored, males release either too little to too much sperm for females to achieve complete fertilization. This conflict could result in a coevolutionary race that may have led to the evolution of internal fertilization in marine organisms. [ABSTRACT FROM AUTHOR]

Many interacting predator–prey populations have a natural tendency to exhibit persistent limit-cycles or damped oscillations, especially in the presence of environmental stochasticity. The restriction of populations into small conservation reserves reduces the scale of ecosystems, and can induce cycling in previously stable predator–prey relationships. During the course of these cycles, the abundance of both predator and prey regularly decrease to low levels. At these times, environmental and demographic stochasticity may cause the extinction of one of the populations. Could culling one or both species at critical times reduce their probability of extinction? We use stochastic dynamic programming to determine the optimal management strategy for oscillation-prone species pairs. Remarkably, if the interventions are enacted at the appropriate time, infrequent culling of a small number of individuals significantly reduces the probability of extinction of the predator. Our approach can be applied to many different ecosystems, and can incorporate more complex system dynamics without a significant increase in computational time. [Copyright &y& Elsevier]

The world''s first dual-fuel, high-temperature fuel cell entered service with the German utility Vattenfall in Berlin in September. The HotModule molten carbonate power plant – manufactured and supplied by Munich-based MTU CFC Solutions – runs on natural gas, methanol or both. The installation is the latest in a number of field trials of MTU''s 250 kWe HotModule units, as the company continues to make progress towards its target of series production in 2006. [Copyright &y& Elsevier]