Status of Southeast Asia's marine sharks and rays

In Southeast Asia, elasmobranchs are particularly threatened. We synthesized knowledge from the peer-reviewed and gray literature on elasmobranchs in the region, including their fisheries, status, trade, biology, and management. We found that 59% of assessed species are threatened with extinction and 72.5% are in decline; rays were more threatened than sharks. Research and conservation is complicated by the socioeconomic contexts of the countries, geopolitical issues in the South China Sea, and the overcapacity and multispecies nature of fisheries that incidentally capture elasmobranchs. The general paucity of data, funds, personnel, and enforcement hinders management. Reduced capacity in the general fishery sector and marine protected areas of sufficient size (for elasmobranchs and local enforcement capabilities) are among recommendations to strengthen conservation.     

Linking life history to landscape for threatened species conservation in a multiuse region

Landscape-scale conservation that considers metapopulation dynamics will be essential for preventing declines of species facing multiple threats to their survival. Toward this end, we developed a novel approach that combines occurrence records, spatial–environmental data, and genetic information to model habitat, connectivity, and patterns of genetic structure and link spatial attributes to underlying ecological mechanisms. Using the threatened northern quoll (Dasyurus hallucatus) as a case study, we applied this approach to address the need for conservation decision-making tools that promote resilient metapopulations of this threatened species in the Pilbara, Western Australia, a multiuse landscape that is a hotspot for biodiversity and mining. Habitat and connectivity were predicted by different landscape characteristics. Whereas habitat suitability was overwhelmingly driven by terrain ruggedness, dispersal was facilitated by proximity to watercourses. Although there is limited evidence for major physical barriers in the Pilbara, areas with high silt and clay content (i.e., alluvial and hardpan plains) showed high resistance to dispersal. Climate subtlety shaped distributions and patterns of genetic turnover, suggesting the potential for local adaptation. By understanding these spatial–environmental associations and linking them to life-history and metapopulation dynamics, we highlight opportunities to provide targeted species management. To support this, we have created habitat, connectivity, and genetic uniqueness maps for conservation decision-making in the region. These tools have the potential to provide a more holistic approach to conservation in multiuse landscapes globally.     

Effect of semantics in the study of tolerance for wolves

As conservation scholars increasingly recognize the critical role of human thought and behavior in determining the persistence of biodiversity across the globe, a growing line of inquiry regarding the validity and comparability of previous applications of core psychological concepts has emerged. Specifically, inconsistent measurement and use of terms, such as attitudes and acceptance, reveal important questions about previous approaches. Given that these concepts differ by definition, yet have been used interchangeably, we explored what drives differences in people's responses when each concept is operationalized in the context of a contested wildlife species, the gray wolf (Canis lupus). To do so, we used data from a 2014 survey of U.S. residents (n = 1287) to test how measures of six concepts (i.e., acceptance, attitudes, benefits, risks, [prior] behavior, and behavioral intentions) often employed in the conservation social sciences were related with a broad set of possible explanatory variables. Despite moderate to strong correlations between all concepts measured (| Pearson's r | = 0.39–0.65, p < 0.001), results revealed considerable variation in their respective relationships with identical explanatory variables. Specifically, although wildlife value orientation (i.e., domination or mutualism) operated fairly consistently across cognitive and behavioral concepts, the relationship between the six concepts and other factors, such as social trust, identification with various interest groups (i.e., hunter, farmer, or rancher, environmentalist, and animal rights advocate), and political ideology (i.e., liberal vs. conservative), varied considerably. Our findings underscore that differences exist in these measures, which could have serious implications for conservationists integrating social science findings in their decision-making processes if they are unaware of the theoretical underpinnings of and distinctions between core psychological concepts.     

Savviness of prey to introduced predators

The prey naivety hypothesis posits that prey are vulnerable to introduced predators because many generations in slow gradual coevolution are needed for appropriate avoidance responses to develop. It predicts that prey will be more responsive to native than introduced predators and less responsive to introduced predators that differ substantially from native predators and from those newly established. To test these predictions, we conducted a global meta-analysis of studies that measured the wariness responses of small mammals to the scent of sympatric mammalian mesopredators. We identified 26 studies that met our selection criteria. These studies comprised 134 experiments reporting on the responses of 36 small mammal species to the scent of six introduced mesopredators and 12 native mesopredators. For each introduced mesopredator, we measured their phylogenetic and functional distance to local native mesopredators and the number of years sympatric with their prey. We used predator and prey body mass as a measure of predation risk. Globally, small mammals were similarly wary of the scent of native and introduced mesopredators; phylogenetic and functional distance between introduced mesopredators and closest native mesopredators had no effect on wariness; and wariness was unrelated to the number of prey generations, or years, since first contact with introduced mesopredators. Small mammal wariness was associated with predator-prey body mass ratio, regardless of the nativity. The one thing animals do not seem to recognize is whether their predators are native.     

Modeling mammal response to fire based on species’ traits

Fire has shaped ecological communities worldwide for millennia, but impacts of fire on individual species are often poorly understood. We performed a meta-analysis to predict which traits, habitat, or study variables and fire characteristics affect how mammal species respond to fire. We modeled effect sizes of measures of population abundance or occupancy as a function of various combinations of these traits and variables with phylogenetic least squares regression. Nine of 115 modeled species (7.83%) returned statistically significant effect sizes, suggesting most mammals are resilient to fire. The top-ranked model predicted a negative impact of fire on species with lower reproductive rates, regardless of fire type (estimate = –0.68), a positive impact of burrowing in prescribed fires (estimate = 1.46) but not wildfires, and a positive impact of average fire return interval for wildfires (estimate = 0.93) but not prescribed fires. If a species’ International Union for Conservation of Nature Red List assessment includes fire as a known or possible threat, the species was predicted to respond negatively to wildfire relative to prescribed fire (estimate = –2.84). These findings provide evidence of experts’ abilities to predict whether fire is a threat to a mammal species and the ability of managers to meet the needs of fire-threatened species through prescribed fire. Where empirical data are lacking, our methods provide a basis for predicting mammal responses to fire and thus can guide conservation actions or interventions in species or communities.     

Importance of conserving large and old trees to continuity of tree-related microhabitats

Protecting structural features, such as tree-related microhabitats (TreMs), is a cost-effective tool crucial for biodiversity conservation applicable to large forested landscapes. Although the development of TreMs is influenced by tree diameter, species, and vitality, the relationships between tree age and TreM profile remain poorly understood. Using a tree-ring-based approach and a large data set of 8038 trees, we modeled the effects of tree age, diameter, and site characteristics on TreM richness and occurrence across some of the most intact primary temperate forests in Europe, including mixed beech and spruce forests. We observed an overall increase in TreM richness on old and large trees in both forest types. The occurrence of specific TreM groups was variably related to tree age and diameter, but some TreM groups (e.g., epiphytes) had a stronger positive relationship with tree species and elevation. Although many TreM groups were positively associated with tree age and diameter, only two TreM groups in spruce stands reacted exclusively to tree age (insect galleries and exposed sapwood) without responding to diameter. Thus, the retention of trees for conservation purposes based on tree diameter appears to be a generally feasible approach with a rather low risk of underrepresentation of TreMs. Because greater tree age and diameter positively affected TreM development, placing a greater emphasis on conserving large trees and allowing them to reach older ages, for example, through the establishment of conservation reserves, would better maintain the continuity of TreM resource and associated biodiversity. However, this approach may be difficult due to the widespread intensification of forest management and global climate change.     

Recovery efficiency of the hydrofluorocarbon (HFC‐134a) by activated carbons of different physicochemical properties

The adsorption characteristics of 1,1,1,2‐tetrafluoroethane (HFC‐134a) on activated carbon were investigated to evaluate the recovery efficiency of HFC‐134a by six activated carbons (two granular activated carbons (GAC1 and GAC2), one high‐surface area activated carbon (HAC), and three activated carbon fibers (ACF10, ACF15, and ACF20)). HFC‐134a adsorption on the activated carbons increased with increase in the specific surface area and pore volume of the activated carbon. The differential heat of the HFC‐134a adsorption decreased with increase in the percentage of the micropore volume to the total pore volume. The adsorption model of HFC‐134a on the activated carbon could be based on the Langmuir model. The constant a of the Langmuir plot of HAC and ACF20 is smaller than GAC1 or GAC2 and ACF10 or ACF15, respectively. The constant W_s of HAC has the largest value. The constant a was correlated to the heat of adsorption. It is concluded that the largest amount of HFC‐134a was adsorbed on HAC, and the least amount of interaction occurred between HFC‐134a and the HAC. The amount of HFC‐134a adsorbed on the activated carbons over time was applied to the Sameshima equation. The adsorption rate constant of HFC‐134a on HAC was the largest. The HAC could be suitable for the recovery of HFC‐134a.     

Regional Ontogeny of New England Salt Marsh Die‐Off

Coastal areas are among the world's most productive and highly affected ecosystems. Centuries of human activity on coastlines have led to overexploitation of marine predators, which in turn has led to cascading ecosystem‐level effects. Human effects and approaches to mediating them, however, differ regionally due to gradients in biotic and abiotic factors. Salt marsh die‐off on Cape Cod, Massachusetts (U.S.A.), triggered by a recreational‐fishing‐induced trophic cascade that has released herbivorous crabs from predator control, has been ongoing since 1976. Similar salt marsh die‐offs have been reported in Long Island Sound and Narragansett Bay (U.S.A.), but the driving mechanism of these die‐offs has not been examined. We used field experiments to assess trophic interactions and historical reconstructions of 24 New England marshes to test the hypotheses that recreational fishing and predator depletion are a regional trigger of salt marsh die‐off in New England and that die‐offs in Long Island Sound and Narragansett Bay are more recent than those on Cape Cod. Predator depletion was the general trigger of marsh die‐off and explained differences in herbivorous crab abundance and the severity of die‐off across regions. Die‐offs in Long Island Sound and Narragansett Bay are following a trajectory similar to die‐off on Cape Cod, but are approximately 20 years behind those on Cape Cod. As a result, die‐off currently affects 31.2% (SE 2.2) of low‐marsh areas in Long Island Sound and Narragansett Bay, less than half the severity of die‐off on Cape Cod. Our results contribute to the growing evidence that recreational fishing is an increasing threat to coastal ecosystems and that studying the effects of human activity at regional scales can provide insight into local effects and aid in early detection and potential remediation. Ontogenia Regional de un Incremento en la Mortandad en una Marisma Salada de Nueva Inglaterra     

双酚A和壬基酚对河蚬呼吸代谢和抗氧化酶活性的影响

为了研究双酚A（Bisphenol A,BPA）和壬基酚（Nonylphenol,NP）对河蚬（Corbicula fluminea）呼吸代谢能力和抗氧化酶活性的影响,探讨BPA和NP对河蚬的毒性作用。以河蚬为受试生物,采用半静态染毒法,研究了BPA和NP对河蚬的单一毒性等级、联合毒性作用类型和对河蚬耗氧率、排氨率以及抗氧化酶系统中SOD、CAT活性的影响。结果显示：① BPA、NP对河蚬的半致死质量浓度（96 h-LC50）分别为6.34和1.09 mg＆#183;L-1,毒性顺序为NP＞BPA,二者均为高毒物质;② BPA-NP对河蚬毒性作用类型为协同作用;③亚急性毒性指标耗氧率、排氨率以及超氧化物歧化酶（SOD）、过氧化氢酶（CAT）对BPA、NP及二者混合物均比较敏感,在本试验的质量浓度范围内（BPA：0.63、0.79、1.59、3.17 mg＆#183;L-1;NP：0.109、0.136、0.271、0.542 mg＆#183;L-1;BPA＋NP：（0.0782＋0.029）、（0.0978＋0.0363）、（0.196＋0.0725）、（0.391＋0.145） mg＆#183;L-1）,河蚬耗氧率、排氨率以及两种酶活性变化均呈现先下降后上升再下降的趋势,其中在BPA、NP和二者混合物的质量浓度较低时,河蚬的耗氧率和排氨率、SOD和CAT活性只有微小降低,随着质量浓度的升高,河蚬耗氧率和排氨率、两个酶活性相对均有所升高,而在质量浓度极高时其耗氧率和排氨率以及两个酶活性才又受到显著性或极显著性的抑制。实验结果显示河蚬耗氧率、排氨率和SOD、CAT活性对水体中酚类内分泌干扰物反应敏感,具有较好的一致性和规律性,耗氧率、排氨率和SOD、CAT活性与其他敏感性指标一起可以作为酚类内分泌干扰物污染的一项早期监测指标。     

Effects of Weighting Schemes on the Identification of Wildlife Corridors Generated with Least‐Cost Methods

The importance of movement corridors for maintaining connectivity within metapopulations of wild animals is a cornerstone of conservation. One common approach for determining corridor locations is least‐cost corridor (LCC) modeling, which uses algorithms within a geographic information system to search for routes with the lowest cumulative resistance between target locations on a landscape. However, the presentation of multiple LCCs that connect multiple locations generally assumes all corridors contribute equally to connectivity, regardless of the likelihood that animals will use them. Thus, LCCs may overemphasize seldom‐used longer routes and underemphasize more frequently used shorter routes. We hypothesize that, depending on conservation objectives and available biological information, weighting individual corridors on the basis of species‐specific movement, dispersal, or gene flow data may better identify effective corridors. We tested whether locations of key connectivity areas, defined as the highest 75th and 90th percentile cumulative weighted value of approximately 155,000 corridors, shift under different weighting scenarios. In addition, we quantified the amount and location of private land that intersect key connectivity areas under each weighting scheme. Some areas that appeared well connected when analyzed with unweighted corridors exhibited much less connectivity compared with weighting schemes that discount corridors with large effective distances. Furthermore, the amount and location of key connectivity areas that intersected private land varied among weighting schemes. We believe biological assumptions and conservation objectives should be explicitly incorporated to weight corridors when assessing landscape connectivity. These results are highly relevant to conservation planning because on the basis of recent interest by government agencies and nongovernmental organizations in maintaining and enhancing wildlife corridors, connectivity will likely be an important criterion for prioritization of land purchases and swaps. Efectos de los Esquemas de Ponderación sobre la Identificación de Corredores para Vida Silvestre Generados con Métodos Menos Costosos