| The behavioural patterns and their cireadian rhythms may be adaptive to the peculiar environmental conditions of subtropical brackish waters where Ba-thygobius soporator Valenciennes, 1837 live. Adult fish were caught at the southern Brazilian coast from mangrove rivers and rocky shores in a bay, where temperature and water salinity vary during the day and through the year. Observation on the behaviour of the animals was undertaken in salinity 8.5ppt, 17.0ppt, 25.5ppt and 34.0ppt, each one in temperatures of 18ºC and 28ºC. Temperature and salinity affect the frequency and intensity of some of the behavioural events, more than its pattern or rhythm. Swimming is rare, decreasing along the day and with temperature increase, being even lower at low salinity;... |
