1. School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria, Australia
2. Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood Highway, Burwood, Victoria, Australia
3. Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, Seewiesen, Germany
4. Departamento de Recursos Naturales y Gestión Ambiental, Estación Experimental Agropecuaria Paraná, Instituto Nacional de Tecnología Agropecuaria (INTA) and CONICET, Oro Verde, Entre Ríos, Argentina