The Blue Crab Fishery in Mississippi

Abstract

Analysis of 670 trawl, seine and marsh net samples collected from July 1971 through June 1973 provided data on the distribution and abundance of blue crabs in Mississippi Sound. Highest average catches were associated with salinities between 5.0 and 15.0 ppt (parts per thousand) and temperatures between 20.0 and 25.OoC. Young crabs congregated in dredged navigational channels and in the marshes that fringe the bays and coastline. Maximum numbers were captured over soft mud bottoms. Peak numbers of zoeae occurred in the summer and fall. Megalopae were collected in all months. Early crab stages appeared throughout the year. Width-frequency distributions suggested rapid growth. Crabs tagged and released in Lake Borgne, La. during the fall of 1971 moved into Mississippi Sound in the vicinity of Cat Island to overwinter. Recoveries of crabs released in the St. Louis Bay, Biloxi Bay and Pascagoula River estuarine systems indicated little movement between estuaries during the spring and summer. Identified parasites included a new microphallid trematode. Commercial landings of blue crabs averaged 1,712,000 pounds for the 20-year period 1953-1972. Catch per unit of effort (pounds/pot day) was low during the spring and fall, peaking in the summer. Rises in the catch per unit of effort closely followed the migration of female crabs into Mississippi Sound.