Labour division in a cooperative breeding bird, the Greyish Baywing (Agelaioides badius): an experimental approach involving nest defence

ROJAS RIPARI, JUAN MANUEL; RIOVITTI, BRUNO; BURGUEÑO, MERCEDES; REBOREDA, JUAN CARLOS; DE MÁRSICO, MARÍA CECILIA

Puerto Iguazú

Congreso; Ornithological Congress of the Americas; 2017

Aves Argentinas / Asociación Ornitológica del Plata - Sociedade Brasileira de Ornitologia - Assosiation of Field Ornithologists

Cooperative breeding in birds is a reproductive system in which one or more adults (helpers) assist others in caring dependent young. In such cooperatively breeding species ?helpers? perform a range of alloparental behaviours, including territory maintenance, nest building, egg incubation or maintenance, offspring feeding, predator defence and nest cleaning. In the current study we aim to describe the nest guarding and predator mobbing behaviour on a cooperative breeding passerine, the Greyish Baywing (Agelaioides baduis). In order to achieve this, we conducted a nest defence experiment at the reserve ?El Destino? (Magdalena, Buenos Aires province, Argentina) during 2015-2016 and 2016-2017 breeding seasons. Taxidermised models of predator (Milvago chimango) and control (Mimus saturninus, Paroaria coronarta and Colaptes melanochloros) models were presented on a random sequential fashion for three minutes, with 20 minutes rest in between registering latency to approximation and mobbing behaviour (n=26). Baywings responded faster (Cox regression; p =0.047) and more intensely (Glmm, p