Temperature and humidity conditions in underground burrows of the lesser Japanese mole, Mogera imaizumii (Talpidae)

Iwasa M.A., Abe R.

P. 31-39

In burrowing mammals, the temperature and humidity in burrows are important microenvironmental factors for the metabolism. To characterize the temperature and relative humidity inside the burrows of the lesser Japanese mole, Mogera imaizumii, digital loggers were set to record these microenvironmental characteristics in underground burrows and the aboveground air as a control. The current temperature and relative humidity were more stable in underground than in aboveground considering that smaller daily differences in both temperature and relative humidity were recognized only in the burrows. The inside temperatures showed up to 26.1 ± 1.2°C irrespective of over 30°C in the aboveground and the mean inside relative humidity showed constantly values over 100% irrespective of the range from 42.8 ± 11.7% to 84.2 ± 9.0% in aboveground through a year. To avoid a restraint of radiation of body heat by evaporation in higher temperature and humidity, lower temperature as possible above 23°C as considered to be the lower limit of the thermoneutral zone seems to be more appropriate condition for the mole. The current results showing the temperatures around the limit (25.1 ± 0.6–26.1 ± 1.2°C) with over 100% relative humidity seem to fit to the more appropriate environment, at least in summer. The current findings means that the high humidity with lower temperature saves energy expended by increasing the metabolic rate in M. imaizumii and probably also in other burrowing mammals.DOI: 10.15298/rusjtheriol.23.1.04