The highly interactive nature of predator-prey relationship is essential for ecosystem conservation; predators have been extirpated, however, from entire ecosystems all over the Earth. Reintroductions comprise a management technique to reverse this trend. Species Distribution Models (SDM) are preemptive tools for release-site selection, and can define levels of habitat quality over the species distribution. The Atlantic Forest of South America has lost most of its apex predators, and Harpy Eagles Harpia harpyja —Earth’s largest eagle—are now limited to few forest pockets in this domain. Harpy Eagles are supposedly widespread in the Amazon Forest, however, where habitat loss and degradation is advancing at a rapid pace. We aim to describe the suitability of threatened Amazonian landscapes for this eagle. We also aim to assess the suitability of remaining Atlantic Forest sites for Harpy Eagle reintroductions. Here we show that that considerable eagle habitat has already been lost in Amazonia due to the expansion of the “Arc of Deforestation”, and that Amazonian forests currently represent 93% of the current distribution of the species. We also show that the Serra do Mar protected areas in southeastern Brazil is the most promising region for Harpy Eagle reintroductions in the Atlantic Forest. Reintroduction and captive breeding programs have been undertaken for Harpy Eagles, building the technical and biological basis for a successful restoration framework. Our distribution range for this species represents a 41% reduction of what is currently proposed by IUCN. Furthermore, habitat loss in Amazonia, combined with industrial logging and hunting suggest that the conservation status of this species should be reassessed. We suggest researchers and conservation practitioners can use this work to help expand efforts to conserve Harpy Eagles and their natural habitats.

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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.

Human-wildlife conflict is a widespread problem that threatens both animals and local livelihoods. When this conflict involves predators, the additional risks to human life worsen the problem. The perceptions of human-predator conflict have been investigated multiple times, usually to generate data for conflict resolution. However, such efforts have largely involved mammals from the order Carnivora. In this work, we tested hypotheses about the feeding habits of two species of constricting anacondas from the genus Eunectes and human perception of risks and attitudes associated with such habits. In particular, we investigated the consequences for the snake after predation on domestic or wild animals. We also tested the relationship between human killing of anacondas and local development indicators -a proxy for general education level. Data were obtained from internet videos using a standardized method for information retrieval. A total of 330 videos of human-anaconda encounters were recovered from ten different South American countries. We found that visual evidence of a recent meal (distended abdomen) and predation on domestic animals did not affect the probability of the anaconda being killed, but this probability increased as the Human Development Index (HDI) diminished and as anaconda size increased. Although retaliatory killing is described as one of main causes of animal mortality following human-wildlife conflicts, our results suggest that killing of anacondas are not retaliatory or related to economic losses, but preventive, because these snakes are seen as life-threatening animals. Adding social context information on human-predator conflicts, together with taxon-free research on this subject can improve our knowledge about human-wildlife conflict. Further research could focus on the actual impacts (direct or indirect) of anacondas on stakeholders, and on the role of other nonmammalian predators in human-wildlife conflicts (whether actual or perceived).Key words: Boidae, livestock predation, Eunectes murinus, Eunectes notaeus, human-wildlife conflict. ResumenEl conflicto entre humanos y animales silvestres es un problema de alcance global que amenaza a los animales y a los estilos de vida locales. Cuando este conflicto incluye predadores, el riesgo adicional impuesto para las vidas humanas agrava el problema. Las percepciones sobre el conflicto predadores-humanos han sido investigadas múltiples veces, con objetivos generalmente relacionados a la obtención de datos para la resolución del conflicto. Pero estos esfuerzos han sido dedicados casi exclusivamente a mamíferos del orden Carnivora. En este trabajo nosotros testeamos hipótesis relacionadas con los hábitos alimentarios de dos especies de anacondas constrictoras del género Eunectes, así como la percepción humana de riesgo y actitudes de estos hábitos. Nosotros también testeamos las relaciones entre mortalidad inducida por humanos y el nivel de desarrollo local -como una aproximación del nivel general de educación. Nosotros obtuvimos los datos...

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Apex predators are threatened globally, and their local extinctions are often driven by failures in sustaining prey acquisition under contexts of severe prey scarcity. The harpy eagle Harpia harpyja is Earth’s largest eagle and the apex aerial predator of Amazonian forests, but no previous study has examined the impact of forest loss on their feeding ecology. We monitored 16 active harpy eagle nests embedded within landscapes that had experienced 0 to 85% of forest loss, and identified 306 captured prey items. Harpy eagles could not switch to open-habitat prey in deforested habitats, and retained a diet based on canopy vertebrates even in deforested landscapes. Feeding rates decreased with forest loss, with three fledged individuals dying of starvation in landscapes that succumbed to 50–70% deforestation. Because landscapes deforested by > 70% supported no nests, and eaglets could not be provisioned to independence within landscapes > 50% forest loss, we established a 50% forest cover threshold for the reproductive viability of harpy eagle pairs. Our scaling-up estimate indicates that 35% of the entire 428,800-km2 Amazonian ‘Arc of Deforestation’ study region cannot support breeding harpy eagle populations. Our results suggest that restoring harpy eagle population viability within highly fragmented forest landscapes critically depends on decisive forest conservation action.

Apex predators are in widespread decline, in many occasions as a consequence of the demise of their prey. Harpy Eagles (Harpia harpyja) are the largest extant eagles on Earth and keystone predators in the tropical forests they inhabit. Although Harpy Eagle prey composition has been described by a number of studies, diet data from primary forests are rare on the literature. Here, I describe the diet of Harpy Eagles living in the Central Suriname Reserve primary forests and review literature data to provide an accessible reference to all known reports of Harpy Eagle prey species. In Central Suriname Nature Reserve, Harpy Eagles made frequent use of game prey such as large primates, large birds, and terrestrial animals, besides what is considered their staple prey, sloths. Nine new prey species were recorded, most of them game animals. This totals 102 prey species when summed with literature data. This information provides new insights into the autecology of Harpy Eagles in Neotropical forests, enabling a better understanding of the ecological effects of apex predator.

Quantifying habitat use is important for understanding how animals meet their requirements for survival and provides useful information for conservation planning. Currently, assessments of range-wide habitat use that delimit species distributions are incomplete for many taxa. The harpy eagle (Harpia harpyja) is a raptor of conservation concern, widely distributed across Neotropical lowland forests, that currently faces threats from increasing habitat loss and fragmentation. Here, we use a logistic regression modelling framework to identify habitat resource selection and predict habitat suitability based on a new method developed from the International Union for the Conservation of Nature Area of Habitat range metric. From the habitat use model, we performed a gap analysis to identify areas of high habitat suitability in regions with limited coverage in the Key Biodiversity Area (KBA) network. Range-wide habitat use indicated that harpy eagles prefer areas of 70-75 % evergreen forest cover, low elevation, and high vegetation heterogeneity. Conversely, harpy eagles avoid areas of >10 % cultivated landcover and mosaic forest, and topographically complex areas. Our habitat use model identified a large continuous area across the pan-Amazonia region, and a habitat corridor from the Chocó-Darién ecoregion of Colombia running north along the Caribbean coast of Central America. Little habitat was predicted across the Atlantic Forest biome, which is now severely degraded. The current KBA network covered ∼18 % of medium to high suitability harpy eagle habitat exceeding the target representation (10 %). Four major areas of high suitability habitat lacking coverage in the KBA network were identified in the Chocó-Darién ecoregion of Colombia, western Guyana, and north-west Brazil. We recommend these multiple gaps of habitat as new KBAs for strengthening the current KBA network. Modelled area of habitat estimates as described here are a useful tool for large-scale conservation planning and can be readily applied to many taxa.