Body temperature and foraging behaviour of the Eurasian otter (Lutra lutra), in relation to water temperature |
| |
Authors: | H. Kruuk P. T. Taylor G. A. T. Mom |
| |
Affiliation: | Institute of Terrestrial Ecology, Banchory AB31 4BY, Scotland |
| |
Abstract: | The effects of water temperature (Tw) on core body temperature (Tb) and foraging behaviour were studied in four free-ranging and one captive otter Lutra lutra in NE Scotland. The free-ranging animals were observed in and around two freshwater lochs, and measurements were made of Tw (2–16°C), Tb at the beginning and end of swimming bouts, lengths of swimming bouts, and dive times and intervals. Tb ranged from 35.9 to 40.4°C (mean 38.1°C). At the beginning of a period of activity and of a swimming bout. Tb rose significantly; during swimming it fell at a rate of 2.3°C/h, independent of Tw. Dive intervals were longer in colder waters, but this was probably due to other, seasonal environmental changes (perhaps water level). Tw had no significant effect on length of swimming bouts or on Tb. Although otters entered water with increased Tb, they exited when Tb was not significantly different from the mean resting Tb. The data suggest that otters maintain Tb irrespective of Tw, by increasing it before entering water, then either exiting at a given Tb, or at an earlier time determined by other environmental conditions. |
| |
Keywords: | |
|
|