Peep, Squeal and Claim: Complex Territorial Call Emission Across Social Contexts in a Neotropical Torrent Frog

ABSTRACT

Acoustic signals are central to torrent frog social behavior, and while sexual selection and adaptation to stream noise have been well studied through advertisement calls, territorial calls remain comparatively overlooked. We detailed the complex structure of male territorial calls of Hylodes perere (Anura: Hylodidae) in a protected area of the Atlantic Rainforest, southeastern Brazil and described their context of emission. We tested whether their parameters correlate with male body size, as well as temperature and stream geophony, all known to influence advertisement calls. Territorial calls were either simple or complex, composed of notes A (a short peep‐like sound) and B (a longer squeal‐like sound). Simple calls were predominant (86.8%); note A was present in 80.8% of the calls, while note B was present in 32.4% of them. Males emitted territorial calls mainly during daytime and in the presence of nearby males, in many instances accompanied by visual signals. Territorial calls were also emitted in the presence of a female. Body size correlated negatively with the duration of simple‐A calls, and temperature correlated negatively with the duration of complex calls. However, stream geophony did not influence parameters of territorial calls. Our results underscore that territorial calls are a crucial component of the species' behavioral repertoire, linked with environmental temperature but not stream noise, indicating different selective mechanisms compared with advertisement calls.