Vocal behaviour and ecology of syntopic Balloon Frogs from Central India

Most amphibians call but why do they call? Well, a male frog can call to attract a female or to defend his territory. As a part of the research, a team of scientists in Asia decided to study two elusive and syntopic species of balloon frogs – Marbled Balloon Frog and Indian Balloon Frog, and the findings of the study are published in BMC Zoology. Not much is known about their ecology and behaviour since they are highly secretive and spend most of their life underground. They surface only for a few days to breed. The research is also summarised in this video.

The two elusive syntopic species of Balloon Frogs, Uperodon systoma and U. globulosus

When breeding in same habitat, species may be forced to utilise the same habitat. This may increase the risk of cross breeding, which may result in unsuccessful reproduction. The researchers were interested to find ‘How do these two frog species overcome this problem and breed successfully?’. And they found that the two balloon frog species adapted to diverge in their acoustic behaviour by making a clear segregation in call properties. Helping them to distinguish their calls… making it easier to detect by females.

Acoustic segregation in the call properties of Uperodon systoma and U. globulosus. Our results demonstrated that the advertisement calls of U. systoma are pulsatile with a call rate of3.00 ± 0.97 calls per second while those of U. globulosus are not pulsatile with a lower call rate of 0.53 ± 0.22 calls per second. For both species, the variations in call properties among individuals was higher than that within individual, a pattern consistent with that of other fossorial anurans. The body condition and air temperature did not significantly impact the call properties of either species.

The two balloon frog species also used different calling locations within the same habitat. Creating a calling microhabitat partitioning. These strategies allowed them to breed successfully and help them co-exist!

Breeding microhabitat segregation between Uperodon systoma and U. globulosus. we successfully demonstrated that there is a clear segregation in calling site microhabitat between the two species, where U. globulosus calls floating close to the bank of the waterbody while U. systoma calls floating further away from the bank

Also, both the species have a potential of individual recognition through individual calls as shown in this research study.

The outcome of the Beecher’s index (HS) showed that the calls of U. systoma can be used to identify 14 different individuals and the calls of U. globulosus can be used to identify 26 different individuals.

Conclusion: This study provides the first detailed analysis of the vocal behaviour of elusive marbled balloon frog and Indian Balloon Frog and highlighting the potential for pre-mating isolation, character displacement and assortative mating in these two syntopic species. Leading to the association between acoustic and calling microhabitat niche as an important behavioural and ecological trait.

Prasad V. K., Chuang M-F., Das A., Ramesh K., Yi Y., Dinesh K P. & Borzée A. (2022). Coexisting good neighbours: acoustic and calling microhabitat niche partitioning in two elusive syntopic species of Balloon Frogs, Uperodon systoma and U. globulosus (Anura: Microhylidae) and potential of individual vocal signatures. BMC Zoology. 7:27. DOI: 10.1186/s40850-022-00132-x

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s