Unravelling the decision making of foraging vultures: insights from a field experiment
Optimal Foraging Theory (OFT) integrates both the consumer and the resource, yet their simultaneous assessment is uncommon. Vultures represent an ideal model for OFT studies because carrion requires no capture effort and minimal handling, allowing them to focus primarily on food searching. Here, we combined GPS tracking of 61 Iberian griffon vultures (consumers) with photo-trapping monitoring of 49 carcasses (resources) to assess the determinants of vulture foraging and the consequences for carrion consumption in two areas with different carrion abundances. First, we determined the importance of different factors (distance to the resource, hunger and competition) in the decisions of individuals of whether to descend or not on a carcass. Second, we compared carrion consumption patterns (time of carcass discovery and consumption, and maximum number of vultures gathered around the carcass) between areas. We found that distance, rather than hunger, is the primary factor determining whether a vulture descends to a carcass. In parallel, carrion was consumed similarly in areas with different resource availabilities. These findings indicate that vultures tend to eat whenever a nearby opportunity arises, consistent with a type-I functional response.
Authors
- José A. Sánchez‐Zapata (ORCID: https://orcid.org/0000-0001-8230-4953)
- Marcos Moleón (ORCID: https://orcid.org/0000-0002-3126-619X)
- Jorge Martínez Carracedo (ORCID: https://orcid.org/0000-0001-8017-2598)
- Zebensui Morales‐Reyes (ORCID: https://orcid.org/0000-0002-4529-8651)
- Eneko Arrondo (ORCID: https://orcid.org/0000-0003-1728-9800)
- Patrick McAllister (ORCID: https://orcid.org/0000-0002-0243-1555)
- José A. Donázar (ORCID: https://orcid.org/0000-0002-9433-9755)
- Roberto Pascual‐Rico (ORCID: https://orcid.org/0000-0002-7340-1230)
- Martina Scacco (ORCID: https://orcid.org/0000-0003-4821-4051)
- Ainara Cortés‐Avizanda (ORCID: https://orcid.org/0000-0002-9674-6434)
Institutions
- Universitat de Miguel Hernández d'Elx (ES)
- Consejo Superior de Investigaciones Científicas (ES)
- University of Ulster (GB)
- Universidad de La Laguna (ES)
- Universidad de Granada (ES)
- University of Konstanz (DE)
- Max Planck Institute for Ornithology (DE)
- Estación Biológica de Doñana (ES)
- Mediterranean Institute for Advanced Studies (ES)
Publication Details
- Journal
- Royal Society Open Science
- Published
- 2025-04-01
- DOI
- https://doi.org/10.1098/rsos.250085
- Citations
- 3
- Primary Topic
- Animal Behavior and Reproduction
- Type
- article
- Field-Weighted Citation Impact
- 9.08
Funders
- Ministerio de Ciencia, Innovación y Universidades
- Ministerio de Economía y Competitividad
- Generalitat Valenciana
- Junta de Andalucía
- European Regional Development Fund
- Agencia Estatal de Investigación