Mother-offspring chemical communication and tadpole aggregation in a Neotropical foam-nesting frog

Abstract

Abstract Communication during parental care represents an advantage for eliciting offspring behaviour and sibling recognition. In aquatic environments, chemical communication is usually the most effective, playing different roles in amphibian parental behaviour. Attending females of some Neotropical anurans (Leptodactylus) lead entire tadpole schools through the water. However, little is known about this aggregation behaviour, such as the type of signal used by attending females or if they are specific between mothers and offspring. Here we conducted behavioural experiments to investigate these questions. Firstly, we tested the effect of visual, tactile, and chemical stimulus of attending females on tadpole aggregation behaviour. Following, we compared the effects of the chemical stimulus from attending females with those from other conspecifics (non-attending females and males) on schooling behaviour. Finally, we tested whether tadpoles prefer related attending females instead of unrelated ones. Our results indicated that only chemical stimulus from attending females, and not visual or tactile, increased tadpoles´ aggregation time. Chemical stimulus from non-attending females and males did not affect tadpoles’ behaviour. Contrary to what we expected, we did not find school preference for related attending females. We were able to demonstrate the presence of chemical signals in mother-tadpole school relationship of Leptodactylus species. Besides, we showed that chemical signals both attract and aggregate tadpoles, which can be crucial for attending females, who guide the entire school through aquatic habitats. Furthermore, our results suggest that tadpoles do not prefer related attending females and may benefit from following unrelated attending female tacking advantage of alloparental care.