Effective conservation planning of Iberian amphibians based on a regionalization of climate-driven range shifts

Amphibians are severely affected by climate change, particularly in regions where droughts prevail and water availability is scarce. The extirpation of amphibians triggers cascading effects that disrupt the trophic structure of food webs and ecosystems. Dedicated assessments of the spatial adaptive potential of amphibian species under climate change are, therefore, essential to provide guidelines for their effective conservation. I used predictions about the location of suitable climates for 27 amphibian species in the Iberian Peninsula from a baseline period to 2080 to typify shifting species’ ranges. The time at which these range types are expected to be functionally important for the adaptation of a species was used to identify full or partial refugia; areas most likely to be the home of populations moving into new climatically suitable grounds; areas most likely to receive populations after climate adaptive dispersal; and climatically unsuitable areas near suitable areas. I implemented an area prioritization protocol for each species to obtain a cohesive set of areas that would provide maximum adaptability and where management interventions should be prioritized. A connectivity assessment pinpointed where facilitative strategies would be most effective. Each of the 27 species had distinct spatial requirements but, common to all species, a bottleneck effect was predicted by 2050 because source areas for subsequent dispersal were small in extent. Three species emerged as difficult to maintain up to 2080. The Iberian northwest was predicted to capture adaptive range for most species. My study offers analytical guidelines for managers and decision makers to undertake systematic assessments on where and when to intervene to maximize the persistence of amphibian species and the functionality of the ecosystems that depend on them.     

Effects of Amazonian flying rivers on frog biodiversity and populations in the Atlantic rainforest

Given the speed at which humans are changing the climate, species with high degrees of endemism may not have time to avoid extinction through adaptation. We investigated through teleconnection analysis the origin of rainfall that determines the phylogenetic diversity of rainforest frogs and the effects of microclimate differences in shaping the morphological traits of isolated populations (which contribute to greater phylogenetic diversity and speciation). We also investigated through teleconnection analysis how deforestation in Amazonia can affect ecosystem services that are fundamental to maintaining the climate of the Atlantic rainforest biodiversity hotspot. Seasonal winds known as flying rivers carry water vapor from Amazonia to the Atlantic Forest, and the breaking of this ecosystem service could lead Atlantic Forest species to population decline and extinction in the short term. Our results suggest that the selection of morphological traits that shape Atlantic Forest frog diversity and their population dynamics are influenced by the Amazonian flying rivers. Our results also suggest that the increases of temperature anomalies in the Atlantic Ocean due to global warming and in the Amazon forest due to deforestation are already breaking this cycle and threaten the biodiversity of the Atlantic Forest hotspot.     

Boosting large-scale river connectivity restoration by planning for the presence of unrecorded barriers

Conservation decisions are invariably made with incomplete data on species’ distributions, habitats, and threats, but frameworks for allocating conservation investments rarely account for missing data. We examined how explicit consideration of missing data can boost return on investment in ecosystem restoration, focusing on the challenge of restoring aquatic ecosystem connectivity by removing dams and road crossings from rivers. A novel way of integrating the presence of unmapped barriers into a barrier optimization model was developed and applied to the U.S. state of Maine to maximize expected habitat gain for migratory fish. Failing to account for unmapped barriers during prioritization led to nearly 50% lower habitat gain than was anticipated using a conventional barrier optimization approach. Explicitly acknowledging that data are incomplete during project selection, however, boosted expected habitat gains by 20–273% on average, depending on the true number of unmapped barriers. Importantly, these gains occurred without additional data. Simply acknowledging that some barriers were unmapped, regardless of their precise number and location, improved conservation outcomes. Given incomplete data on ecosystems worldwide, our results demonstrate the value of accounting for data shortcomings during project selection.     

Integrating Paleobiology,Archeology, and History to Inform Biological Conservation

The search for novel approaches to establishing ecological baselines (reference conditions) is constrained by the fact that most ecological studies span the past few decades, at most, and investigate ecosystems that have been substantially altered by human activities for decades, centuries, or more. Paleobiology, archeology, and history provide historical ecological context for biological conservation, remediation, and restoration. We argue that linking historical ecology explicitly with conservation can help unify related disciplines of conservation paleobiology, conservation archeobiology, and environmental history. Differences in the spatial and temporal resolution and extent (scale) of prehistoric, historic, and modern ecological data remain obstacles to integrating historical ecology and conservation biology, but the prolonged temporal extents of historical ecological data can help establish more complete baselines for restoration, document a historical range of ecological variability, and assist in determining desired future conditions. We used the eastern oyster (Crassostrea virginica) fishery of the Chesapeake Bay (U.S.A.) to demonstrate the utility of historical ecological data for elucidating oyster conservation and the need for an approach to conservation that transcends disciplinary boundaries. Historical ecological studies from the Chesapeake have documented dramatic declines (as much as 99%) in oyster abundance since the early to mid‐1800s, changes in oyster size in response to different nutrient levels from the sixteenth to nineteenth centuries, and substantial reductions in oyster accretion rates (from 10 mm/year to effectively 0 mm/year) from the Late Holocene to modern times. Better integration of different historical ecological data sets and increased collaboration between paleobiologists, geologists, archeologists, environmental historians, and ecologists to create standardized research designs and methodologies will help unify prehistoric, historic, and modern time perspectives on biological conservation. Integración de Paleobiología, Arqueología e Historia para Informar a la Biología de la Conservación     

Lethal Effects of Water Quality on Threatened California Salamanders but Not on Co‐Occurring Hybrid Salamanders

Biological invasions and habitat alteration are often detrimental to native species, but their interactions are difficult to predict. Interbreeding between native and introduced species generates novel genotypes and phenotypes, and human land use alters habitat structure and chemistry. Both invasions and habitat alteration create new biological challenges and opportunities. In the intensively farmed Salinas Valley, California (U.S.A.), threatened California tiger salamanders (Ambystoma californiense) have been replaced by hybrids between California tiger salamander and introduced barred tiger salamanders (Ambystoma tigrinum mavortium). We conducted an enclosure experiment to examine the effects habitat modification and relative frequency of hybrid and native California tiger salamanders have on recruitment of salamanders and their prey, Pacific chorus frogs (Pseudacris regilla). We tested whether recruitment differed among genetic classes of tiger salamanders (hybrid or native) and pond hydroperiod (seasonal or perennial). Roughly 6 weeks into the experiment, 70% (of 378 total) of salamander larvae died in 4 out of 6 ponds. Native salamanders survived (n = 12) in these ponds only if they had metamorphosed prior to the die‐offs. During die‐offs, all larvae of native salamanders died, whereas 56% of hybrid larvae died. We necropsied native and hybrid salamanders, tested water quality, and queried the California Department of Pesticide Regulation database to investigate possible causes of the die‐offs. Salamander die‐offs, changes in the abundance of other community members (invertebrates, algae, and cyanobacteria), shifts in salamander sex ratio, and patterns of pesticide application in adjacent fields suggest that pesticide use may have contributed to die‐offs. That all survivors were hybrids suggests that environmental stress may promote rapid displacement of native genotypes. Efectos Letales de la Calidad del Agua sobre Salamandras de California Amenazadas pero no sobre Salamandras Híbridas Concurrentes     

Poaching Risks in Community‐Based Natural Resource Management

Poaching can disrupt wildlife‐management efforts in community‐based natural resource management systems. Monitoring, estimating, and acquiring data on poaching is difficult. We used local‐stakeholder knowledge and poaching records to rank and map the risk of poaching incidents in 2 areas where natural resources are managed by community members in Caprivi, Namibia. We mapped local stakeholder perceptions of the risk of poaching, risk of wildlife damage to livelihoods, and wildlife distribution and compared these maps with spatially explicit records of poaching events. Recorded poaching events and stakeholder perceptions of where poaching occurred were not spatially correlated. However, the locations of documented poaching events were spatially correlated with areas that stakeholders perceived wildlife as a threat to their livelihoods. This result suggests poaching occurred in response to wildlife damage occurred. Local stakeholders thought that wildlife populations were at high risk of being poached and that poaching occurred where there was abundant wildlife. These findings suggest stakeholders were concerned about wildlife resources in their community and indicate a need for integrated and continued monitoring of poaching activities and further interventions at the wildlife‐agricultural interface. Involving stakeholders in the assessment of poaching risks promotes their participation in local conservation efforts, a central tenet of community‐based management. We considered stakeholders poaching informants, rather than suspects, and our technique was spatially explicit. Different strategies to reduce poaching are likely needed in different areas. For example, interventions that reduce human‐wildlife conflict may be required in residential areas, and increased and targeted patrolling may be required in more remote areas. Stakeholder‐generated maps of human‐wildlife interactions may be a valuable enforcement and intervention support tool. Riesgos de Cacería Furtiva en el Manejo de Recursos Naturales Basado en Comunidades     

Reduced effect of Tasmanian devil facial tumor disease at the disease front

Pathogen-driven declines in animal populations are increasingly regarded as a major conservation issue. The Tasmanian devil (Sarcophilus harrisii) is threatened with extinction by devil facial tumor disease, a unique transmissible cancer. The disease is transmitted through direct transfer of tumor cells, which is possible because the genetic diversity of Tasmanian devils is low, particularly in the major histocompatibility complex genes of the immune system. The far northwest of Tasmania now holds the last remaining disease-free wild devil populations. The recent discovery of unique major histocompatibility complex genotypes in the northwestern region of Tasmania has raised the possibility that some animals may be resilient to the disease. We examined the differences in the epidemiology and population effects of devil facial tumor disease at 3 well-studied affected sites in eastern Tasmania and 1 in western Tasmania (West Pencil Pine). In contrast to the 3 eastern sites, there has been no rapid increase in disease prevalence or evidence of population decline at West Pencil Pine. Moreover, this is the only onsite at which the population age structure has remained unaltered 4 years after the first detection of disease. The most plausible explanations for the substantial differences in population effects and epidemiology of the disease between eastern and western sites are geographic differences in genotypes or phenotypes of devils and functional differences between tumor strains in the 2 regions. We suggest that conservation efforts focus on identifying whether either or both these explanations are correct and then, if resistance alleles exist, to attempt to spread the resistant alleles into affected populations. Such assisted selection has rarely been attempted for the management of wildlife diseases, but it may be widely applicable.     

Challenges to interdisciplinary research in ecosystem-based management

Despite its necessity, integration of natural and social sciences to inform conservation efforts has been difficult. We examined the views of 63 scientists and practitioners involved in marine management in Mexico's Gulf of California, the central California coast, and the western Pacific on the challenges associated with integrating social science into research efforts that support ecosystem-based management (EBM) in marine systems. We used a semistructured interview format. Questions focused on how EBM was developed for these sites and how contextual factors affected its development and outcomes. Many of the traditional challenges linked with interdisciplinary research were present in the EBM projects we studied. However, a number of contextual elements affected how mandates to include social science were interpreted and implemented as well as how easily challenges could be addressed. For example, a common challenge is that conservation organizations are often dominated by natural scientists, but for some projects it was easier to address this imbalance than for others. We also found that the management and institutional histories that came before EBM in specific cases were important features of local context. Because challenges differed among cases, we believe resolving challenges to interdisciplinary research should be context specific.     

Inadvertent advocacy

Policy advocacy is an issue regularly debated among conservation scientists. These debates have focused on intentional policy advocacy by scientists, but advocacy can also be unintentional. I define inadvertent policy advocacy as the act of unintentionally expressing personal policy preferences or ethical judgments in a way that is nearly indistinguishable from scientific judgments. A scientist may be well intentioned and intellectually honest but still inadvertently engage in policy advocacy. There are two ways to inadvertently engage in policy advocacy. First, a scientist expresses an opinion that she or he believes is a scientific judgment but it is actually an ethical judgment or personal policy preference. Second, a scientist expresses an opinion that he or she knows is an ethical judgment or personal policy preference but inadvertently fails to effectively communicate the nature of the opinion to policy makers or the public. I illustrate inadvertent advocacy with three examples: recovery criteria in recovery plans for species listed under the U.S. Endangered Species Act, a scientific peer review of a recovery plan for the Northern Spotted Owl (Strix occidentalis caurina), and the International Union for Conservation of Nature's definition of threatened. In each example, scientists expressed ethical judgments or policy preferences, but their value judgments were not identified as such, and, hence, their value judgments were opaque to policy makers and the public. Circumstances suggest their advocacy was inadvertent. I believe conservation scientists must become acutely aware of the line between science and policy and avoid inadvertent policy advocacy because it is professional negligence, erodes trust in scientists and science, and perpetuates an ethical vacuum that undermines the rational political discourse necessary for the evolution of society's values. The principal remedy for inadvertent advocacy is education of conservation scientists in an effort to help them understand how science and values interact to fulfill the mission of conservation science.     

Assessing citizen contributions to butterfly monitoring in two large cities

Citizen science may be especially effective in urban landscapes due to the large pool of potential volunteers. However, there have been few evaluations of the contributions of citizen scientists to knowledge of biological communities in and around cities. To assess the effectiveness of citizen scientists' monitoring of species in urban areas, we compared butterfly data collected over 10 years in Chicago, Illinois (U.S.A.), and New York City, New York (U.S.A.). The dates, locations, and methods of data collection in Chicago were standardized, whereas data from New York were collected at any location at any time. For each city, we evaluated whether the number of observers, observation days (days on which observations were reported), and sampling locations were associated with the reported proportion of the estimated regional pool of butterfly species. We also compared the number of volunteers, duration of volunteer involvement, and consistency of sampling efforts at individual locations within each city over time. From 2001 to 2010, there were 73 volunteers in Chicago and 89 in New York. During this period, volunteers observed 86% and 89% of the estimated number of butterfly species present in Chicago and New York, respectively. Volunteers in New York reported a greater proportion of the estimated pool of butterfly species per year. In addition, more species were observed per volunteer and observation day in New York, largely due to the unrestricted sampling season in New York. Chicago volunteers were active for more years and monitored individual locations more consistently over time than volunteers in New York. Differences in monitoring protocol--especially length of sampling season and selection protocol for monitoring locations--influenced the relationship between species accrual and sampling effort, which suggests these factors are important in volunteer-based species-monitoring programs.