In parallel with economic and social changes, mutualism in human-vulture relations has virtually disappeared worldwide. Here, we describe the mutualistic relationship between humans and the globally threatened Egyptian vulture in Socotra, Yemen. By analyzing both the spatial distribution of vultures and the amount of human byproducts they consume, we show that human activities enable the maintenance of the densest population of this rare scavenger, whereas vultures provide a key regulating service by disposing of up to 22.4% of the organic waste annually produced in towns. Globalization is impacting the archipelago, and therefore policies that better integrate societal needs and biodiversity conservation are urgently needed. We propose a win-win solution that relies on the restructuring of the mutualism, shifting from regulating services toward cultural services. Our study highlights the necessity of reconciling trade-offs between biodiversity conservation and economic development in a framework of global change affecting Middle Eastern countries.

Despite increasing work detailing the presence of foraging specializations across a range of taxa, limited attention so far has been given to the role of spatiotemporal variation in food predictability in shaping individual resource selection. Here, we studied the exploitation of human-provided carrion resources differing in predictability by Canarian Egyptian vultures (Neophron percnopterus majorensis). We focussed specifically on the role of individual characteristics and spatial constraints in shaping patterns of resource use. Using high-resolution GPS data obtained from 45 vultures tracked for 1 year, we show that individual vultures were repeatable in both their monthly use of predictable and semi-predicable resources (feeding station vs. farms) and monthly levels of mobility (home range size and flight activity). However, individual foraging activities were simultaneously characterized by a high degree of (temporal) plasticity in the use of the feeding station in specific months. Individual rank within dominance hierarchy revealed sex-dependent effects of social status on resource preference in breeding adults, illustrating the potential complex social mechanisms underpinning status-dependent resource use patterns. Our results show that predictable food at feeding stations may lead to broad-scale patterns of resource partitioning and affect both the foraging and social dynamics within local vulture populations.

1. Long-lived avian scavengers are threatened worldwide and thus, are common targets of conservation plans. However, scientific evidence of both the factors limiting populations and effectiveness of management actions are greatly needed in order to develop more efficient and successful conservation strategies.2. We assessed the effectiveness of conservation actions applied within a LIFE-Nature project aimed at improving the long-term survival of the critically endangered Canarian Egyptian vulture: including education campaigns for public awareness and control of illegal poisoning and the modification of power lines to reduce the risk of accidents. We formulated a multievent capture-mark-recapture model to obtain estimates of survival for juvenile, subadult and adult birds accounting for probabilities of resight, recovery and losses of metal and colour rings.3. Models supported a substantial enhancement in survival for subadult and adult birds and a moderate improvement for juveniles after the implementation of LIFE actions. Ring loss probabilities became notably high in the middle to long term. 4. Poisoning events became very rare after LIFE was implemented, suggesting a positive effect of environmental education and awareness campaigns. Entanglements and collisions in power lines were also efficiently mitigated. Instead, electrocutions became the most identified cause of death in the post-LIFE stage. Synthesis and applications.Our results highlight the improvement of survival in a threatened island vulture population after the implementation of a European LIFE conservation project. On small islands, with small human populations and few stakeholders, education and awareness campaigns can be especially effective for biodiversity conservation. We also demonstrate the need to complement conservation programmes with long-term monitoring, which is essential to evaluate the effectiveness of actions, especially for long-lived species.

Vultures are one of the most threatened bird groups globally. Although many of the threats faced by vultures have been identified, the impact of human activities on the social life of vultures has received little attention. In this paper, we emphasize the need to integrate vulture sociality into conservation practice. First, we summarize current knowledge on vulture social behavior, and the evolutionary and ecological roots of their breeding systems. We describe the existence of contrasting gradients in social foraging strategies and hierarchical social structures among colonial and territorial breeders associated with species (and population) reliance on carrion differing in size and predictability. We also highlight the potential role of vulture gatherings in maintaining population-level social structures and for mate-finding given high mate-selectivity. Next, based on this social framework, we discuss the impact of human activities on social foraging, territory structures, resource partitioning processes, and mating dynamics. However, little is known about how disruptions of social habits may have contributed to vulture population declines and/or may impede their recovery. Lastly, we provide directions for future research on vulture socio-ecology that may improve current conservation efforts. We encourage researchers and wildlife managers to pay more attention to natural carrion diversity underlying vulture social system diversity, especially when implementing supplementary feeding programs, and to consider the complex mating and settlement dynamics in reintroduction programs. Overall, we stress that understanding the complex social life of vultures is critical to harmonize their conservation with anthropogenic activities.

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