Population ecology and conservation of long-lived avian scavengers

Many avian scavenger populations are vanishing worldwide. Understanding the causes of these declines and tackling them on the basis of scientific evidence is a primary goal of for managers and ecologists. Our target species is the Egyptian vulture (Neophron percnopterus) whose populations dropped dramatically during the 20th century in India,the Circunmediterranean and the Middle East (>50% Over the last three generations) plus ongoing declines through much of the rest of its African range. The species is currently considered as “Globally Endangered” with a total world population below 30000 individuals. We develop long-term monitoring programs in regions where the species has divergent trends. These programs which essentially involves the annual monitoring of territories and individualized marking, numerous studies have been carried out focusing on basic ecology, demography, foraging ecology and behaviour.

Canarian Egyptian vultures

Since 1998 we monitor the relict Egyptian vulture population living in the Eastern Canary islands (Fuerteventura and Lanzarote). This is a multidisciplinary project integrating research lines in demography, behavioural ecology, toxicology and genetics. Relying on continuous ringing, 90% of the population is now individually identified. In the short and medium future, our main interest is aimed to the movement ecology and to deep into individual foraging strategies for which 47 birds have been marked with GPS radiotransmitters. Thanks to the close relationship with local authorities evidence-based conservation measures are applied within adaptive management schemes. As a result, this endemic subspecies once reduced to only 20 breeding territories is currently expanding reaching more than 77 occupied breeding places and 360 individuals in 2019.

During the development of the Project three PHD. Thesis have been finished and more than fifteen papers published.

Featured publications:

van Overveld, T., García-Alfonso, M., Dingemanse, N.J., Bouten, W., Gangoso, L., de la Riva, M., Serrano, D. y Donázar, J.A. 2018. Food predictability and social status drive individual resource specializations in a territorial vulture. Scientific Reports 8, Article number: 15155 (2018).

García-Alfonso, M., Morales-Reyes, Z., Gangoso, L., Bouten, W., Sánchez-Zapata, J.A., Serrano, D., Donázar, J.A. 2018. Probing into farmers’ perceptions of a globally endangered ecosystem service provider. Ambio 48:900-912.

Badia-Boher, J.A., Sanz-Aguilar, A., de la Riva, M., Gangoso, L., van Overveld, T., García-Alfonso, M., Pérez-Luzardo, O., Suarez-Pérez, A., Donázar, J.A. 2019. Evaluating European LIFE conservation projects: improvements in survival of an endangered vulture. Journal of Applied Ecology 56:1210-1219.

van Overveld, T., Gangoso, L., García-Alfonso, M., Bouten, W., de la Riva, M., Donázar, J.A. 2020. Seasonal grouping dynamics in a territorial vulture: ecological drivers and social consequences. Behavioural Ecology and Sociobiology.

Links:

• https://canarianegyptianvulture.com/

• https://www.lifegyptianvulture.it/es/el-proyecto/

Egyptian vultures in the Ebro valley.

This project is carried out since 1986 in the Bardenas Reales Natural Park and neighbouring areas of the Ebro valley in Northern Spain. In this region the species has declined by around 70% in the last 40 years. We have deepened into the role that the availability of trophic resources and unnatural mortality have had in this precipitous decline of the population. Interests also focus on the effect that novel human pressures, fundamentally, the growing tourism in protected areas, can have for the viability of the population of the target species and other large birds of prey as well as for and the functionality of ecological processes like the cosume of livestock carcasses.

Featured publications:

Cortés-Avizanda, A., Colomer, M.A., Margalida, A., Ceballos, O., Donázar, J.A. 2015. Modeling the consequences of the demise and potential recovery of a keystone-species: wild rabbits and avian scavengers in Mediterranean landscapes. Scientific Reports 5, 17033; doi: 10.1038/srep17033.

Sanz-Aguilar, A., Cortés-Avizanda, A., Serrano, D., Blanco, G., Ceballos, O., Grande, J.M., Tella, J.L., Donázar, J.A. 2017. Sex- and age-dependent patterns of survival and breeding success in a long-lived endangered avian scavenger. Sci. Rep. 7, 40204; doi: 10.1038/srep40204.

Donázar, J.A., Ceballos, O., Cortés-Avizanda, A. 2018. Tourism in protected areas: Disentangling road and traffic effects on intra-guild scavenging processes. Science of Total Environment 630:600-608.

Blanco, G., Cortés-Avizanda, A., Frías, Ó., Arrondo, E., Donázar, J.A. 2019. Livestock farming practices modulate vulture diet-disease interactions, Global Ecology and Conservation.

Donázar, J.A., Cortés-Avizanda, A., Ceballos, O. E. Arrondo, J.M. Grande, D. Serrano. 2020. Epizootics and sanitary regulations drive long-term changes in fledgling body condition of a threatened vulture. Ecological Indicators 113.