Seasonal variation of thermal safety margin of Rhinella arenarum.

SANABRIA E.; QUIROGA L.; CORTEZ R.; MARINERO V.; MORENO D.; CATALDO A.

Mendoza

Congreso; Biology Society XXVIII Annual Scientific Meeting; 2010

SBC

Body temperature in amphibians regulates a wide range of physiological processes. We studied the variation in thermal safety margins of R. arenarum between dry and wet seasons in the Monte desert. Recorded in the laboratory the critical thermal maximum (CTMax) and in the field the operating temperatures (To), body temperatures (Tc), high ambient temperatures (Ta-max), minimum (Ta-min) in the dry (DS) and wet (WS) season. We collected by hand 35 individuals (18 in WS and 17 DS). The CTMax was obtained by exposing the samples to a heat source, with a rate of temperature increase of 1 ºC per minute. We found that this parameter varies significantly between seasons (U = 31, p