Allee effects have important implications for many aspects of basic and applied ecology. The benefits of aggregation of conspecific individuals are central to Allee effects, which have led to the widely held assumption that social species are more prone to Allee effects. Robust evidence for this assumption, however, remains rare. Furthermore, previous research on Allee effects has failed to adequately address the consequences of the different levels of organisation within social species’ populations. We review available evidence of Allee effects and model the role of demographic and behavioural factors that may combine to dampen or strengthen Allee effects in social species. We use examples across various species with contrasting social structure, including carnivores, bats, primates and eusocial insects. Building on this, we provide a conceptual framework that allows for the integration of different Allee effects in social species.
Shared ecological knowledge about the impacts of biological invasions can facilitate the collective action necessary to achieve desired management outcomes. Since its introduction to an island archipelago in South America, the North American beaver has caused major changes to the ecosystem. We examined landowners’ mental models of how beavers impact ecosystem services in riparian areas to understand the potential to implement a large-scale eradication program. We used ethno- graphic interviews to characterize individual landowners’ perceptions about beaver-caused changes to ecosystems and landowners’ wellbeing, and examined the degree to which they are shared. While the eradication initiative focuses on ecosystem integrity, landowners considered impacts on provisioning ser- vices to be most salient. Landowners did not have a highly shared causal model of beaver impacts, which indicates a diverse knowledge system. This lack of consensus on how beavers impact riparian areas provides some optimism for garnering support for eradication, and also offers insights into challenges with mental modeling methodologies.
Nearly forty years old, the US Endangered Species Act (ESA) remains a landmark act in conservation and one of the world’s most comprehensive laws designed to prevent species extinctions and support recovery efforts for imperiled species. A controversial law and often subject to political attack, the ESA is successful overall but not without difficulties. Those who enforce the ESA, for example, struggle to achieve viable recovery goals for many species.
This forward-thinking, innovative volume provides a roadmap for designing species conservation programs on the ground so they are effective and take place upstream of regulation, which will contribute to a reduction in lawsuits and other expenses that arise after a species is listed. Proactive Strategies for Species Protection is a guidebook for anyone anywhere interested in designing programs that incentivize environmental stewardship and species conservation.
This volume brings together ecologists, foresters, social scientists, lawyers, ranchers, government officials, and others to create a legal, scientific, sociological, financial, and technological foundation for designing solutions that incentivize conservation action for hundreds of at-risk species—prior to their potential listing under the ESA. Proactive Strategies for Protecting Species explores the perspectives, opportunities, and challenges around designing and implementing pre-listing programs and approaches to species conservation.
Research on seafood fraud is a nascent topic. A recent study makes the claim that “mislabeling results in the sale of items of better conservation status and nearly equivalent price.” However the study has a number of issues that questions its main conclusions. First, based on the data and results that are presented, there appear to be errors and some of the conclusions are not supported. Second, there may be a bias in the analyses that favors the conclusions. Third, details are lacking regarding the analyses, challenging their verification. ACS published a letter in the journal Conservation Letters describing the issues. Seafood fraud results from natural and human systems interacting in complex ways, which is likely resulting in place-based consequences. We argue that in order to characterize the system dynamics and provide insights into the financial and ecological implications of seafood fraud, a more careful and cautious approach is required.
Biodiversity offsets are becoming increasingly common across a portfolio of settings: national policy, voluntary programs, international lending, and corporate business structures. Given the diversity of ecological, political, and socio-economic systems where offsets may be applied, place-based information is likely to be most useful in designing and implementing offset programs, along with guiding principles that assure best practice. We reviewed the research on biodiversity offsets to explore gaps and needs. While the peer-reviewed literature on offsets is growing rapidly, it is heavily dominated by ecological theory, wetland ecosystems, and U.S.-based research. Given that majority of offset policies and programs are occurring in middle- and low-income countries, the research gaps we identified present a number of risks. They also present an opportunity to create regionally based learning platforms focused on pilot projects and institutional capacity building. Scientific research should diversify, both topically and geographically, in order to support the successful design, implementation, and monitoring of biodiversity offset programs.
Territorial use rights in fisheries (TURFs) are becoming a widely promoted tool to enhance the sustainability of small-scale fisheries. In 1991, Chile established a national coastal TURF policy that gave legal authority to assign exclusive access rights to artisanal fisher organizations. In 2014, there were several hundred TURFs decreed to fisher organizations in different biophysical and socioeconomic settings. To date, research assessing TURF implementation has generally been based on a few case studies and have had mixed results. Here, we present results from a survey of 535 fishers from 55 different artisanal fisher organizations. e survey consisted of three open-ended questions that explore users’ perceptions of the main problems, benefits, and improvements concerning assigned TURFs. Main key problems, as perceived by fishers, include increased costs associated with surveillance and poaching, and the variability and sometimes lack of financial returns. Despite strong price drops in exported species, TURFs have provided incentives for innovation and stewardship, and fishers are generally unwilling to relinquish them...
Ants are one of the most cosmopolitan invasive taxa: dozens of species have invaded islands and continental areas around the globe. Invasive ants continue to colonize new ecosystems having direct and indirect negative impacts on natural and managed ecosystems. Thus, in many cases, eradication is often a desirable management action. While invasive ant eradications have increased over the past 15 years, the success rate of ant eradications is low compared to other invasive species. With colleagues from CISRO Australia and University College of London, ACS reviewed ant eradications worldwide in order to assess the practice and identify knowledge gaps and challenges.