A radio telemetry study of movement in the giant Tasmanian freshwater crayfish, Astacopsis gouldi

The movements of eight adult Tasmanian giant crayfish, Astacopsis gouldi, (carapace lengths: 120-191 mm) were recorded using radio telemetry. Transmitters were attached to the animals' carapaces and their positions were fixed at least daily. Tracking durations varied from 14-144 days, depending on the life span of the transmitters. All animals showed substantial periods of inactivity, lasting from 1 to 10 days; in one animal, inactivity appeared to be related to brooding. Activity was not strongly nocturnal, and when active, the animals moved large distances. One animal covered 700m in a single night, and the stream lengths over which animals were active during the 5-month study ranged from 90-2200m. Animals often returned to the same refuge after excursions.