Population structure of Thenus orientalis and T. indicus (Decapoda: Scyllaridae) in northeastern Australia

Abstract

Thenus indicus and T. orientalis have mutually exclusive distributions. Both species populations were characterised by contagious distributions. Mean density of T. indicus was 1.78 (±0.15) lobsters ha-1, while that of T. orientalis was 2.02 (±0.13). In both populations, depth and sediment type were significantly correlated with abundance. T. indicus was most abundant in depths of 10-30m and where sediments were characterised by a preponderance of fine sands and silt. T. orientalis was most abundant in depths of 40-50m and where sediments were composed primarily of medium-coarse sands. In both species, mean size varied significantly throughout the year as a function of growth and recruitment. Male and female T. indicus were equally abundant, while male T. orientalis were significantly more abundant than females. -from Author