Using Citizen Science Data to Investigate the Diet of the Mountain Caracara (Phalcoboenus megalopterus) and White-throated Caracara (Phalcoboenus albogularis)

Abstract

The Mountain Caracara (Phalcoboenus megalopterus) and White-throated Caracara (Phalcoboenus albogularis) are two sister species each with a limited distribution along the Andes from Ecuador to Tierra del Fuego. They occur in remote areas and are among the least known caracaras, and their diet has been little studied, particularly for the White-throated Caracara. We investigated the diet of these two caracaras by analyzing photographs provided by citizen scientists and obtained from the Macaulay Library (eBird) and iNaturalist platforms. We obtained 43 photographs for Mountain Caracara and 42 photographs for White-throated Caracara that could be used to identify food items. Photographs of the Mountain Caracara showed the species mainly feeding on carrion, often of domestic animals, followed by human foods and garbage. Photographs of the White-throated Caracara showed this species mainly feeding on carrion and garbage. However, we did find photographs of both caracaras feeding on wild species including camelids, rodents, birds, lizards, and some invertebrates. Further research should investigate possible effects of human-derived items in the diet of these caracaras, such as malnutrition due to consumption of inappropriate foods, and effects of ingestion of plastics and toxic substances.