Population Studies of the Blue Crabs of the Galveston

Abstract: Trawls, seines, and trammel nets were used to sample the Galve^s^ ton Bay crab populations. The data collected were used in determining the seasonal abundance of the crabs as compared to previous years sampling. Blue crab populations in 1962 appeared to be larger than in 1961. The female population lagged behind the male in abundance all months in 1962, except April, October, and December. The movement of adult crabs appeared to be governed by their search for food, reproductive cycle, and seasonal temperatures. Juveniles remained in the bay all seasons, moving toward the primary bay as they grew. Growth rate of the juvenile crabs was 0.4 millimeter per day„ Objective: To sample the blue crab populations with various collecting devices in an attempt to determine their seasonal abundance, migration patterns, and growth rate as related to environmental conditions. Procedures: Blue crab populations were sampled semi-monthly at permanent stations in the Galveston Bay complex (Figure 1). Either a 10 foot traw