INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Human induced energy changes affect the abundances of a guild of raptors in Patagonia, Argentina
Autor/es:
BARBAR, FACUNDO
Lugar:
Iguazú, Misiones
Reunión:
Congreso; Ornithological Congress of the Americas; 2017
Institución organizadora:
Asociation of Field Ornithology, Aves Argentinas, Sociedaide Brasileira de Orniologia
Resumen:
The Energetic Equivalence Rule (EER) states that the relationship between abundances of organisms (N) and their masses (M), is based on the available energy in the systems and the species metabolic needs, remaining constant with a value around αEER=-0.75, (N↔M (-0.75)). Humans have altered energy fluxes worldwide through their activities. Particularly, in northwestern Patagonia, small towns and cities emplaced as islands in a pristine environment, provide new resources of energy through rubbish dumps, but also with the introduction of livestock and exotic species. The European hare (Lepus europaeus) is one of the most invasive ones in the area reaching high abundances and serving as a new food-item for many top predators. We evaluate the effect of these human made changes in energy fluxes on the abundances of a raptor guild. We conducted 4000 Km of road transect, counting raptors and livestock during the day and hares during the night, to estimate each species density in the field. On average, we found that the raptor guild followed the EER although with a smaller coefficient than theoretically proposed (αTOT=-0.56±0.062), indicating that Patagonia has higher abundances of bigger raptor species. Forest environments with human settlements tend to favor smaller species (αFOR=-0.96±0.23) while steppe areas with high abundances of hares and livestock favor bigger species (αSTE=-0.52±0.14). Our results highlight that these human effects can alter top predator communities even when these are relatively new. This should be considered as it impacts in the ecology and conservation of several species and their environment.