Movement and Tagging of the Giant Red Sea Cucumber Parastichopus californicus in Southeastern Alaska

The southeastern Alaska fishery for Parastichopus californicus is growing and information on spatial redistribution for a population would benefit managers in determining appropriate stock assessment times, providing data on population characteristics, and supplying biological reasons for when the fishery should occur. Individual P. californicus were tagged in-situ and tracked every three months over 4-6 days for one year to determine seasonal daily movements. Density was measured monthly for one year at three depths near Juneau, Alaska, to determine seasonal movement trends. A study to determine the effects of tagging was also conducted. Movements ranged from 0 to 34.5 m/h with variation among sites and season. Density and movements were highest in summer and lowest in fall with the majority of animals found at depth transect, 12.2 m. Tagging increased animal movements for up to 48 h from the time of initial tagging. Stock assessments should be conducted in spring and summer to coincide with increased animal densities, and with the fishery occurring in fall and winter, potentially providing refuge for a portion of the population. Overall, results indicate closed or geographically limited populations with little possibility of animal migration or repopulation of over harvested areas.