Abstract
The adult carabid beetle Pterostichus brevicornis tolerates freezing under natural conditions. Laboratory tests confirm that winter beetles tolerate temperatures below -35°C, whereas summer beetles die if frozen at -6.6°C. Winter beetles can be cooled to about -10°C before freezing, and they thaw near -3.5°C. Summer beetles thaw at -0.7°C. To avoid freezing damage even in winter beetles, cooling rates must be near 20°C per hour or less.