Range-wide habitat use of the Harpy Eagle indicates four major tropical forest gaps in the Key Biodiversity Area network

Quantifying habitat use is important for understanding how animals meet their requirements for survival and provides 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 habitat loss and fragmentation. Here, we use penalized logistic regression to identify species-habitat associations and predict habitat suitability based on a new International Union for the Conservation of Nature range metric, termed Area of Habitat. From the species-habitat 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 species richness. Conversely, Harpy Eagles avoid areas of >10% cultivated landcover and mosaic forest, and topographically complex areas. Our species-habitat model identified a large continuous area of potential habitat across the pan-Amazonia region, and a habitat corridor from the Choco-Darien 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 Harpy Eagle habitat exceeding a target biodiversity area representation of 10%, based on species range size. Four major areas of high suitability habitat lacking coverage in the KBA network were identified in north and west Colombia, western Guyana, and north-west Brazil. We recommend these multiple gaps of habitat as new KBAs for strengthening the current KBA network. Modeled area of habitat estimates as described here is a useful tool for large-scale conservation planning and can be readily applied to many taxa. Lay Summary center dot Quantifying habitat use is key to understanding animals' requirements for survival and can inform spatial conservation planning by mapping species range limits. center dot Species that inhabit remote, hard-to-survey areas lack sufficient location data and there is a need to be able to predict into poorly sampled areas to estimate the potential area of habitat. center dot Using species distribution models, we identified Harpy Eagle range limits, habitat area, and key biodiversity area coverage across the species range. center dot Harpy Eagles prefer areas of 70-75% evergreen forest cover, high vegetation species richness, and low elevation. center dot Key biodiversity areas covered 18% of highly suitable Harpy Eagle habitat but with key gaps in coverage in north and west Colombia, western Guyana, and north-west Brazil. center dot Our method of calculating habitat area estimates based on a predictive spatial model is a useful tool for large-scale conservation planning and can be readily applied to many taxa.

Automated summary

Quantifying habitat use is essential for understanding animal survival requirements and conservation planning. The study focused on the Harpy Eagle, a raptor species facing threats from habitat loss. It identified the species-habitat associations and predicted habitat suitability based on the Area of Habitat metric. The study recommended new Key Biodiversity Areas (KBAs) to strengthen the current KBA network, as several important areas of high habitat suitability were lacking coverage.