Growth of the Deep-Water Mud Shrimp Solenocera Melantho De Man, 1907 (Decapoda, Penaeoidea, Solenoceridae) in Kagoshima Bay, Southern Japan

Abstract

The deep-water mud shrimp Solenocera melantho is commercially important as the main target species for small-scale trawlers in Kagoshima Bay, southern Japan. A total of 4,837 specimens were collected from the central area of the bay from January 1993 to June 1994. Length frequency analysis was used to examine the growth and longevity of S. melantho. Both males and females were first recruited in winter with modal sizes of around 15 mm carapace length. Growth was best described by the Pauly & Gaschutz growth equation as Lt = 33.09{1 - exp[-0.857(t/12 + 0.525) - (0.538/2π) sin(2π (t/12 - 0.404))]} for males and Lt = 45.76{1- exp[-0.777(t/12 + 0.401) - (0.452/2π) sin(2π (t/12 - 0.583))]} for females, where Lt is carapace length (mm) at age t (months). Females grow faster and reach larger sizes earlier than males of the same age group. Growth rates and the occurrence of soft-shelled individuals in both sexes were highest between winter and spring, and lowest during the spawning season between summer and early winter (June to December). The longevity of both malc and female S. melantho was estimated to be around 37 months. The allometric relationship between body weight and carapace length was represented by significantly different equations between sexes.