Conservation Letters最新文献

What factors render a species more vulnerable to extinction? In reptiles, foraging mode is a fundamental ecological dimension: some species actively search for immobile prey, whereas others ambush mobile prey. Foraging mode is linked to diet, morphology, movement ecology, and reproductive output, and hence plausibly might affect vulnerability to threatening processes. Our analyses of data on 1543 taxa revealed links between foraging mode and (IUCN) conservation status, but in opposite directions in the two main squamate groups. Ambush-foraging snakes were more threatened and with declining populations than were active searchers, whereas lizards showed the reverse pattern. This divergence may be linked to differing consequences of foraging mode for feeding rates and reproductive frequency in snakes versus lizards. Our findings underscore the need for taxon-specific conservation management, particularly in groups such as reptiles that have been neglected in global conservation prioritization.

Australia is a global leader in land clearing and biodiversity loss. The overwhelming majority of land clearing within Australia and, globally, is driven by agricultural conversion. The importance of agricultural lands also leads to the concentration of habitat protection in landscapes that do not support productive land uses, which might contribute to species conservation in marginal habitat. Using an integrated agricultural capability map and threatened vertebrate fauna range maps, we show that observed biases in protected area location have varied impacts at the species level. Specifically, threatened vertebrate fauna with habitat capable of supporting high-value productive lands received less protection and experienced greater habitat loss. Similarly, almost all species assessed received protection in the portions of their ranges less conducive to productive land uses. Finally, we identify regions of Australia at risk of future land clearing and the species likely to bear the brunt of the impacts. Our results demonstrate the importance of protecting land capable of supporting productive uses to conserve the most affected threatened species.

Agricultural commodity production is a major driver of tropical deforestation and biodiversity loss. Natural rubber from Hevea brasiliensis, a valuable commodity without viable substitutes, has recently been included in the European Union (EU) deforestation regulation that aims to halt imports of goods containing embedded deforestation. Sustained growth in demand for rubber is driven by increasing tire production, caused by rising transport flows and personal car ownership. We show that average natural rubber yields remain static, meaning 2.7–5.3 million ha of additional plantations could be needed by 2030 to meet demand. A systematic literature search identified 106 case studies concerning transitions to and from rubber, revealing that substantial rubber plantation area expansion since 2010 has occurred at the expense of natural forest. Eliminating deforestation from rubber supply chains requires support for millions of smallholder growers to maintain or increase production from existing plantations, without land or water degradation. Supply chain traceability efforts offer opportunities to deliver such support. While the inclusion of rubber in EU legislation is a positive step, it is critical to ensure that smallholders are not marginalized to avoid exacerbating poverty, and that other markets follow suit to avoid displacement of rubber-driven deforestation to unregulated markets.

Climate change is threatening marine systems, and its widespread and dynamic effects are creating challenges for designing and managing marine protected areas (MPAs). The majority of recommendations for climate-resilient MPAs focus on enhancing ecological resilience to disturbance and updating management strategies to respond as changes occur. Here, we assess how existing recommendations for climate resilience are applied in real-world MPA management, using criteria from five key management components: objectives, assessments, design, monitoring, and management. Our review evaluates 172 management plans for 555 MPAs across 52 countries and written in nine languages. We find that MPA management plans contain many underlying scientific and management principles for promoting resilience to climate change, even when “climate change” or related terms are not specifically included: plans include long-term objectives (93.6%), threat-reduction strategies (99.4%), monitoring programs (97.7%), and adaptive management (93%). However, there is substantial variation in the degree to which plans explicitly incorporate climate change into their strategies, from not mentioning it at all (21.5%) to developing detailed climate change-specific action plans (20.9%), with most somewhere in between. In addition to identifying common gaps across management plans, we also provide practical examples of activities MPA managers are undertaking to address climate change.

Illegal fishing, unregulated bycatch, and market demand for certain products (e.g., fins) are largely responsible for the rapid global decline of shark and ray populations. Controlling trade of endangered species remains difficult due to product variety, taxonomic ambiguity, and trade complexity. The genetic tools traditionally used to identify traded species typically target individual tissue samples, and are time-consuming and/or species-specific. Here, we performed high-throughput sequencing of trace DNA fragments retrieved from dust and scraps left behind by trade activities. We metabarcoded “shark-dust” samples from seven processing plants in the world's biggest shark landing site (Java, Indonesia), and identified 61 shark and ray taxa (representing half of all chondrichthyan orders), more than half of which could not be recovered from tissue samples collected in parallel from the same sites. Importantly, over 80% of shark-dust sequences were found to belong to CITES-listed species. We argue that this approach is likely to become a powerful and cost-effective monitoring tool wherever wildlife is traded.

Our planet is facing increasing challenges: climate change, biodiversity loss, pandemics, poverty, and many other problems closely linked to a deteriorating environment. Meanwhile, one of our most important assets, rangers working in protected and conserved areas responsible for managing large tracts of the planet's lands and waters, are often underutilized, underrecognized and underequipped. They are generally left out of the debate about conservation and sustainable development policy, despite being central to the success of those policies. This paper outlines the need for global leaders across multiple sectors to recognize the profession of rangers as essential planetary health workers and to position rangers more effectively within global conservation and environmental policy mechanisms. It introduces the challenges facing rangers, the emerging diversity of roles within the ranger profession and the important contribution of rangers to conservation and sustainable development. It presents policy and implementation avenues to improve recognition and professionalization of rangers as key executors of conservation and development policy, particularly considering the recent Global Biodiversity Framework ambitions.

Interventions of the host–pathogen dynamics provide strong tests of relationships, yet they are still rarely applied across multiple populations. After American bullfrogs (Rana catesbeiana) invaded a wildlife refuge where federally threatened Chiricahua leopard frogs (R. chiricahuensis) were reintroduced 12 years prior, managers launched a landscape-scale eradication effort to help ensure continued recovery of the native species. We used a before-after-control-impact design and environmental DNA sampling of 19 eradication sites and 18 control sites between fall 2016 and winter 2020–2021 to measure community-level responses to bullfrog eradication, including for two pathogens. Dynamic occupancy models revealed successful eradication from 94% of treatment sites. Native amphibians did not respond to bullfrog eradication, but the pathogens amphibian chytrid fungus (Batrachochytrium dendrobatidis) and ranaviruses were coextirpated with bullfrogs. Our spatially replicated experimental approach provides strong evidence that management of invasive species can simultaneously reduce predation and disease risk for imperiled species.