Rusty crayfish (Orconectes rusticus) movement within and between habitats in Trout Lake, Vilas County, Wisconsin

Abstract

The exotic rusty crayfish, Orconectes rusticus, has invaded northern Wisconsin watersheds and is causing severe ecological alterations. We investigated the processes of rusty crayfish dispersal and movement within Trout Lake, Vilas County, Wisconsin, using a mark and recapture technique. We examined the effects of crayfish size, gender, and original location on distance traveled. Some O. rusticus moved up to 221 m in 2 d, but most crayfish remained in their original habitat (distances ranged from 0–58 m). Distances traveled were similar for both male and female crayfish. Crayfish size did not affect the patterns of movement. Crayfish did not travel greater distances over time, which may be an artifact of 2 groups of crayfish: those that stayed in their local habitat and those that moved far distances. Comparisons with published dispersal and movement data suggest that large movements are observed occasionally in both lotic and lentic habitats. For rusty crayfish, these movements have important implications for invasion rates.