First nesting record of Stripe-breasted Starthroat (Heliomaster squamosus) in Argentina

Abstract

The Stripe-breasted Starthroat (Heliomaster squamosus) is distributed in Brazil. In Argentina, there are three records of the species believed to be vagrant individuals, and none of these records mention aspects of their reproduction. Here, we report for the first time the nesting of the Stripe-breasted Starthroat (H. squamosus) in Argentina. We provide behavioral characteristics, nest details, and the discovery site, as well as photographic material of the reproductive event. The nest was found in a specimen of Eucalyptus sp. near the administration office of El Palmar National Park, Entre Rios, Argentina. In subsequent visits to the site in late 2022, we observed a female individual, which could apparently be the same one, carrying nesting material and in an incubating position in the nest. This is the southernmost record of nesting for the species in South America and the first for the country. Although interspecific reproduction can occur in Trochilidae, we do not rule out a possible expansion of the species' breeding range.