Efficacy of Peeler Pots and Experimental Habitat, Pots for Capture of Premolt Blue Crabs

Abstract

Four designs of peeler pots and habitat pots were tested to determine if construction cost or labor could be minimized without reducing catch rates of peeler (premolt) blue crabs Callinectes sapidus of commercial size (≥75 mm carapace width). Peeler pots had 2.5- or 3.8-cm-mesh wire and two or six adult male blue crabs as bait. Habitat pots were 30 or 45 cm high and either had flagging tape woven among mesh or did not. One pot of each design was deployed at each of five stations in the Wando River, South Carolina, and fished daily (24-hour soak time) from 1 April through 28 June 1980. Overall, habitat pots captured more peelers (0.72/pot-day) than did peeler pots (0.38/pot-day). Peeler-pot catches peaked dramatically during 23–30 April (> 1.6 peelers/pot-day), the week prior to a full moon, and were 97% pubertal-molt females during this peak. Habitat-pot catches were bimodal (16–22 April and 30 May-6 June), and consisted predominately of immature males entering their pubertal molt. Male:female ratios were 1:2.7 for peeler pots and 2.4:1 for habitat pots. The most effective peeler pots for capture of pubertalmolt females were constructed of 2.5-cm-mesh wire and had two bait males. Cannibalism among bait males increased in pots with six bait males, and presence of dead crabs decreased catch rates significantly. Observed differences in catch rates between 2.5- and 3.8-cm-mesh wire were not due to the smaller mesh retaining smaller crabs because premolt crabs (<75 mm total width) were not considered in the analysis. Tape presence did not effectively increase catch rates in habitat pots, but tall pots, with upper and lower chambers, captured significantly more peelers than did short pots with one chamber; the effects of pot height and number of chambers were not distinguished. Catch rates differed significantly among stations, but followed similar patterns for both gear types; the most productive station was an extensive subtidal mud flat. The labor-intensive practice of weaving tape among pot meshes is not recommended, and reducing pot cost by using larger wire mesh for peeler pots or constructing shorter habitat pots does not appear cost-effective. Fishing the best gear designs at the most productive sites and periods would increase catch rates substantially, and both gear types are practical methods of harvesting blue crab peelers in South Carolina estuaries. Received December 21, 1982 Accepted May 21, 1984