Invasion of the acoustic niche: variable responses by native species to invasive American bullfrog calls

Author(s)

Medeiros, Camila Ineu ; Both, Camila ; Grant, Taran ; Hartz, Sandra Maria

• Document type: Journal article
• Source: Biological Invasions; v. 19, n. 2, p. 675-690, FEB 2017.
• Web of Science Citations: 5

Abstract

Biological invasions are a major threat to biodiversity. Invasive species that use acoustic communication can affect native species through interference in the acoustic niche. The American Bullfrog Lithobates catesbeianus is a highly invasive anuran that is widely distributed in the Brazilian Atlantic Rainforest. Adult male bullfrogs emit loud advertisement calls at frequencies that overlap with the calls of several native species of frogs. Given that spectral overlap is a major factor in acoustic masking, the purpose of this study was to test the effects of the acoustic invasion of L. catesbeianus on native frogs that have calls with and without spectral overlap with the invader. In field experiments, we exposed calling males of two overlapping species and two non-overlapping species to recorded bullfrog vocalizations, white noise, and the vocalization of another native frog species. To identify effects, we compared calls recorded before, during, and after exposure. Our results showed that native species altered their calls in response to the bullfrog calls. However, we also observed similar responses to white noise and heterospecific native calls. Both the invasive and heterospecific calls were emitted at low frequencies, which suggests that the observed responses might be specific to low-frequency calls. Our results provide evidence that the introduction of new sounds can cause native species to modify their calls, and that responses to exogenous sounds are species- and stimulus-specific. (AU)

• FAPESP's process: 12/10000-5 - A multi-disciplinary approach to the study of amphibian diversification
• Grantee: Taran Grant
• Support Opportunities: Research Grants - Young Investigators Grants