Studies on the Gobies (Pisces: Gobiidae) of Mississippi Sound and Adjacent Waters. I. Gobiosoma

Abstract

Data are provided on relative abundance, seasonal occur- rence, growth rate, ecological preferences, interspecific relationships, meristics and body proportions of Gobiosoma robustum, G. bosci and G. longipala, the known Gobiosoma species of Mississippi Sound. Compari- sons are made between G. longipala and its Atlantic seaboard cognate G. ginsburgi. The 15-month study, including 818 comparable collections at 17 stations productive of this genus, shows G. robustum to be scarce in mid- winter and most (83%) are taken in salinities from 22.3 - 32.3 o/oo. This species has restricted distribution within the Sound but, where present, may occur in considerable numbers. G. bosci exhibits a distinct preference for salinities below 22.3 o/oo and a size-salinity relationship is indicated wherein fish of the medium standard length classes (11.5- 22.0 mm) prefer low salinity (0.3 - 4.7 o/oo) and smaller fish are most common at higher salinities (14.8 - 24.7 o/oo). Though seldom abun- dant in individual collections, G. bosci is the most widely distributed Gobiosoma in Mississippi Sound. G. longipala is usually present in the area during late summer and fall and in moderate salinities (24.8 - 32.2 o/oo). Though widely distributed in- the Sound, it is less numerous than its local congeners and is seldom taken in quantity. G. longipala and G. ginsburgi are, on the basis of present data, considered to be allopatric species.