Life History of Tug Valley Crayfish Cambarus hatfieldi Loughman, Fagundo, Lau, Welsh & Thoma 2013 (Decapoda: Astacoidea: Cambaridae) in Southwestern West Virginia, USA

Abstract

Life history data for Cambarus hatfieldi Loughman, Fagundo, Lau, Welsh, & Thoma, 2013 were collected from March through December 2018 from Dry Fork at War, West Virginia, USA. Cambarus hatfieldi is syntopic with Cambarus callainus Thoma, Loughman & Fetzner, 2014 through part of its range, with the latter having been listed as threatened by United States Fish & Wildlife Service under the Endangered Species Act in 2016. No ovigerous females with pleopodal eggs were collected; however, mean ovarian egg diameter peaked in July, which correlated with ovigerous females from the West Liberty Crayfish Collection which were collected in August 2009 at nearby Barrenshe Creek. Mature male total carapace length (TCL) ranged from 29.3 to 52.6 mm and mature female TCL ranged from 29.7 to 48.1 mm. Morphometric analysis provided evidence of form change in female C. hatfieldi. Relative abundance of form I males to form II males was greater in March, April, May, October and December; declining below form II going into the summer. Six size classes, or cohorts, were determined by analysis of peaks on monthly histograms of TCL. Cambarus hatfieldi young of the year (YOY) appear to enter the population around October, with delayed growth until Spring.