Abstract: Calls are an important medium for acoustic communication among animals. Analysis of acoustic characteristics is beneficial to understand acoustic communication in frogs. Calling patterns in frogs are speciesspecific and influenced by selection pressures from local environment. From June to October in 2017, the acoustic structure and daily circadian rhythms of calling activity were recorded for 24 individuals of Fejervarya cancrivora that inhabited brackish water and semisaline water. The results showed that F. cancrivora calls were composed of basic syllables, combination calls with the basic syllables, and multisyllabic calls. Furthermore, the calls were frequency modulated. Male individuals called from 20:00-21:00 to 5:00-6:00, with a peak at 2:00-4:00. The numbers of hourly calls of males were not significantly correlated with air temperature or relative humidity (P>0.05). However, the calling behavior ended (5:00-6:00) with rising temperature. F. cancrivora communicated more efficiently via frequency modulation and changes in calling types. The calling behavior of F. cancrivora followed daily circadian rhythms, occurring throughout the night. The beginning and ending time of calling activity was influenced by air temperature. The high relative humidity facilitated the transmission of calls.

Key words: tillage method, soil physicochemical properties, biological characteristics, conservation tillage.