Marine Biologist

Abstract: Blue crabs were sampled with an otter trawl, minnow seine and trammel net at various locations in the lower Laguna Madre. A net of one millimeter mesh was used to sample larval crabs in the surf. Poor catches of juvenile blue crabs by otter trawl in the first part of the 1963 study period were probably due to an unsuccessful spawn reported in 1962. Indications were that mating occurred from April through July, and during October, 1963. A successful spawn occurred in late fall of 1963, as evidenced by an increase of larvae in beach samples in November, and by the prevalence of small juvenile crabs in the bay in November and early December. Objectives: To determine the seasonal abundance, growth rate, and size of crabs in the Upper Laguna Madre. Procedures: The locations of all crab stations are shown in Figure 1. Samples were taken at Stations C-1 through C-3 with a 10-foot trawl of 1 1/4 inch stretch mesh and 1/4 inch liner. Samples were obtained monthly from January throug