Breeding biology of Neotropical Accipitriformes: current knowledge and research priorities

Abstract

Despite the key role that knowledge on breeding biology of Accipitriformes plays in their management and conservation, survey of the state-of-the-art and of information gaps spanning the entire Neotropics has not been done since 1995. We provide an updated classification of current knowledge about breeding biology of Neotropical Accipitridae and define the taxa that should be prioritized by future studies. We analyzed 440 publications produced since 1995 that reported breeding of 56 species. Tere is a persistent scarcity, or complete absence, of information about the nests of eight species, and about breeding behavior of another ten. Among these species, the largest gap of breeding data refers to the former "Leucopternis" hawks. Although 66% of the 56 evaluated species had some improvement on knowledge about their breeding traits, research still focus disproportionately on a few regions and species, and the scarcity of breeding data on many South American Accipitridae persists. We noted that analysis of records from both a citizen science digital database and museum egg collections signifcantly increased breeding information on some species, relative to recent literature. We created four groups of priority species for breeding biology studies, based on knowledge gaps and threat categories at global level. Group I (great scarcity of information, plus higher categories of threat): Leptodon forbesi, Cryptoleucopteryx plumbea, and Buteogallus lacernulatus; Group II (breeding data have recently increased, but threat categories are high): Spizaetus isidori, Accipiter gundlachi, Buteogallus coronatus, Pseudastur occidentalis, and Buteo ventralis; Group III ("Near Treatened" species with still scarce breeding information): Accipiter poliogaster, Accipiter collaris, Buteogallus aequinoctialis, and Pseudastur polionotus; and Group IV (other priority cases): Buteo ridgwayi, Buteo galapagoensis, four eagles (Morphnus guianensis, Harpia harpyja, Spizaetus ornatus and Buteogallus solitarius), Leptodon cayanensis, Accipiter superciliosus, Buteogallus schistaceus, and the three Leucopternis hawks (L. semiplumbeus, L. melanops and L. kuhli). We also discuss the way that novel breeding data can show in what manners different species and populations are responding to environmental changes.