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Abstract In the face of an accelerating extinction crisis, scientists must draw insights from successful conservation interventions to uncover promising strategies for reversing broader declines. Here, we synthesize cases of recovery from a list of 362 species of large carnivores, ecologically important species that function as terminal consumers in many ecological contexts. Large carnivores represent critical conservation targets that have experienced historical declines as a result of direct exploitation and habitat loss. We examine taxonomic and geographic variation in current extinction risk and recovery indices, identify conservation actions associated with positive outcomes, and reveal anthropogenic threats linked to ongoing declines. We find that fewer than 10% of global large carnivore populations are increasing, and only 12 species (3.3%) have experienced genuine improvement in extinction risk, mostly limited to recoveries among marine mammals. Recovery is associated with species legislation enacted at national and international levels, and with management of direct exploitation. Conversely, ongoing declines are robustly linked to threats that include habitat modification and human conflict. Applying lessons from cases of large carnivore recovery will be crucial for restoring intact ecosystems and maintaining the services they provide to humans.

IntroductionChanges in temperature can fundamentally transform how species interact, causing wholesale shifts in ecosystem dynamics and stability. Yet we still have a limited understanding of how temperature-dependence in physiology drives temperature-dependence in species-interactions. For predator-prey interactions, theory predicts that increases in temperature drive increases in metabolism and that animals respond to this increased energy expenditure by ramping up their food consumption to meet their metabolic demand. However, if consumption does not increase as rapidly with temperature as metabolism, increases in temperature can ultimately cause a reduction in consumer fitness and biomass via starvation.MethodsHere we test the hypothesis that increases in temperature cause more rapid increases in metabolism than increases in consumption using the California spiny lobster (Panulirus interruptus) as a model system. We acclimated individual lobsters to temperatures they experience sacross their biogeographic range (11, 16, 21, or 26°C), then measured whether lobster consumption rates are able to meet the increased metabolic demands of rising temperatures.Results and discussionWe show positive effects of temperature on metabolism and predation, but in contrast to our hypothesis, rising temperature caused lobster consumption rates to increase at a faster rate than increases in metabolic demand, suggesting that for the mid-range of temperatures, lobsters are capable of ramping up consumption rates to increase their caloric demand. However, at the extreme ends of the simulated temperatures, lobster biology broke down. At the coldest temperature, lobsters had almost no metabolic activity and at the highest temperature, 33% of lobsters died. Our results suggest that temperature plays a key role in driving the geographic range of spiny lobsters and that spatial and temporal shifts in temperature can play a critical role in driving the strength of species interactions for a key predator in temperate reef ecosystems.