Shared territorial defence in the suboscine Aphrastura spinicauda

Abstract

Territorial behaviour is an active and typically aggressive behaviour used to defend resources. Here, we investigated the presence of shared territorial defence behaviour during conspecific intrusions in the Thorn-tailed Rayadito (Aphrastura spinicauda), a suboscine species that generally does not maintain long-term pair bonds. We found that, compared to females, males displayed more alarm calling during their response, approached closer and were also more physically aggressive towards conspecific intruders. Despite these differences, the defence behaviour of males and females was highly correlated during territorial responses to simulated intruders. To our knowledge, this is the first report of coordinated or joint territorial defence in a South American suboscine that generally only maintains short-term pair bonds.