Main aerial top predator of the Andean Montane Forest copes with fragmentation, but may be paying a high cost

ZULUAGA, SANTIAGO; VARGAS, F. H.; ARÁOZ, R.; GRANDE, J. M.

Global Ecology and Conservation

Elsevier

Lugar: Amsterdam; Año: 2022 vol. 37 p. 1 - 12

2351-9894

Large raptors are the most mobile top predators in fragmented landscapes and, consequently, theyare key components of ecosystems. However, large raptors (e.g. eagles), requiring large areas offorested habitat, are also among the most threatened groups of raptors in the world and aredirectly and indirectly affected by habitat loss and fragmentation. The Black-and-chestnut Eagle(Spizaetus isidori) is a forest dependent species with a long period of natal dispersal. Here, we aimto assess home range size, mortality, and habitat selection of juvenile Black-and-chestnut Eaglesduring their natal dispersal in three populations within fragmented landscapes of the Tropical andSubtropical Andean Montane Forests of South America. During the first year of natal dispersal,juveniles occupied large home ranges (mean = 996.3 km2; SD± 606; range = 294–2130 km2).While juvenile eagles made their natal dispersal through fragmented landscapes, they consistentlyselected areas with higher remaining forest cover, medium elevations, and steeper slopes than themean available in the landscape. Our study showed that juvenile eagles can tolerate a certainlevel of fragmentation during the natal dispersal period, although they also face high mortalityduring this same period. Four of the six (67 %) tagged juvenile eagles died during the studyperiod. The high mobility of juvenile eagles may help maintain key ecosystem functions withinfragmented landscapes of South America. In order to maintain viable populations of this toppredator, it is urgent to mitigate non-natural mortality, mainly from direct human persecution, infragmented landscapes.