Conservation implications of harpy eagle Harpia harpyja predation patterns

Abstract

Knowledge of the food habits of threatened taxa is key for their effective conservation, especially in top predators where prey species are frequently also hunted by humans. The harpy eagle Harpia harpyja is the largest living eagle, and is considered Near Threatened by the IUCN. Its main threats are persecution by humans and habitat loss. Predation patterns of this species have been the subject of several descriptive studies, each reflecting the idiosyncrasies of the study area. Systematizing these data permits a transition from descriptive treatments of harpy food habits to a predictive focus, based on defensive prey strategies and foraging theory. This generates information that can enhance management and conservation decisions. Literature data were summarized and standardized, allowing comparison between studies. Results indicate that harpy eagles feed mainly on sloths and other prey with passive antipredator strategies, with sloths accounting for 50% of prey items and biomass consumed. Large monkeys such as howlers (Alouatta spp.) and capuchins (Sapajus and Cebus spp.) are the next most important prey, but combined, primates form only ~20% of the consumed prey biomass. Predation seldom occurs on animals weighing more than 5 kg. This is positive from a conservation point of view, since sloths are not game species, precluding competition between harpy eagles and subsistence hunting.

Juvenile Dispersal of Harpy Eagles (Harpia harpyja) in Ecuador

“…Different aspects of the biology of the Harpy Eagle have been studied, including trophic ecology (Fowler and Cope 1964, Piana 2007, Lenz and dos Reis 2011, Aguiar-Silva et al 2014, Miranda 2016 and breeding behavior (Rettig 1978,Álvarez-Cordero 1996, Muñiz-López 2007, Rotenberg et al 2012. Although there are some studies on its movement ecology (Álvarez-Cordero 1996, Campbell-Thompson et al 2012, Muñiz-López et al 2012, Aguiar-Silva and Sanaiotti 2013, due to the difficulty of observing this species, some aspects of its spatial ecology (e.g., juvenile dispersal) are still poorly known.…”

Penny and penny laid up will be many: large Yellow anacondas do not disregard small prey

“…Prey composition of many vertebrate species have been described, including carnivorous mammals (Cavalcanti & Gese, ), predatory reptiles (Bhupathy, Ramesh & Bahuguna, ) and birds of prey (Miranda, ). Although several trends stand out, theoretical analysis of dietary data are still uncommon.…”

Top‐down limitation of mesopredators by avian top predators: a call for research on cascading effects at the community and ecosystem scale

“…Developing research on the role of top avian predators in tropical ecological networks Studies are being carried out on the ecology of Verreaux's Eagle Aquila verreauxii, Martial Eagle Polemaetus bellicosus and African Crowned Eagle Stephanoaetus coronatus in sub-Saharan Africa (McPherson et al 2016, Murgatroyd et al 2016, van Eeden et al 2017) and the Harpy Eagle Harpia harpyja in South and Central America (Miranda 2015, Miranda et al 2018. Further research is needed on the role of these large eagles on mesopredator habitat use and population dynamics in diverse ecosystems.…”

“…Despite their large trophic spectrum and evidence that mammalian mesopredators are regular prey of both species (Lourenc ßo et al 2011), research has until now only focused on the effects of Eagle-Owl presence on intraguild avian predators. This natural recolonization process could be used as a before-after-control-impact (BACI) experimental design integrating methodological aspects described in the previous section (monitoring mesopredator spatial (Miranda 2015, Miranda et al 2018. Further research is needed on the role of these large eagles on mesopredator habitat use and population dynamics in diverse ecosystems.…”