How Food Distribution Affects Social Behavior in Migratory Birds
Author Information
Author(s): Ainara Cortés-Avizanda, Pablo Almaraz, Martina Carrete, José A. Sánchez-Zapata, Antonio Delgado, Fernando Hiraldo, José A. Donázar
Primary Institution: Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, Sevilla, Spain
Hypothesis
The spatial distribution of our focal species will closely follow that of clumped resources in Europe, whereas in sub-Saharan Africa the species will be widespread, only showing aggregated distributions linked to pulsed resources.
Conclusion
Bird sociality at feeding grounds is closely linked to the pattern of spatial distribution and predictability of trophic resources, which are ultimately induced by human activities.
Supporting Evidence
- Birds were detected at predictable feeding sources in Europe, with maximum counts of 143 black kites.
- Food availability was significantly higher in African transects, with 91.9% detecting livestock.
- Stable isotope analysis showed dietary overlap in summering areas but not in wintering areas.
Takeaway
Birds that migrate between Europe and Africa change how they group together based on where food is available. In Europe, they gather around predictable food sources, while in Africa, they spread out more.
Methodology
The study used constrained zero-inflated Generalized Additive Models to analyze the spatial distribution of two migratory bird species in relation to food availability.
Limitations
The study may not account for all environmental factors affecting bird distribution and sociality.
Participant Demographics
The study focused on two species of migratory birds: the black kite and the Egyptian vulture.
Statistical Information
P-Value
p<0.0001
Statistical Significance
p<0.0001
Digital Object Identifier (DOI)
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