FISHERY BULLETIN: VOL. 85, NO. 3 



sition of G. fenneri as a function of depth and trap 

 type, and examines aspects of adult life history 

 and reproductive biology of this species in the 

 South Atlantic Bight. 



METHODS 



Cruises were made during the period from 20 

 June 1985 to 21 February 1986 on board the 

 South Carolina Wildlife and Marine Resources 

 Department (SCWMRD) research vessels Oregon 

 and Lady Lisa , and the NOAA ship Chapman. All 

 vessels were equipped with large capacity hy- 

 draulic systems and a heavy duty pot hauler. 



Two commercially available trap designs were 

 used to sample crabs. The Fathoms Plus^ traps 

 are oval (85 cm long x 66 cm wide x 30 cm high) 

 and constructed of injection molded plastic. The 

 trap has two side-entry funnels that can be en- 

 larged by removing more of the plastic funnel's 

 inner lip. The original, oval funnel opening is 10 

 cm X 20 cm. Both funnels were cut out to a maxi- 

 mum opening size of 14 cm x 22 cm. Traps were 

 weighted with chain, making the total weight of 

 each trap 11 kg. The Florida trap is an injection 

 molded, high-impact plastic version of a Florida 

 spiny lobster trap (82 cm long x 61 cm wide x 45 

 cm high). The top of the trap is constructed of 

 wood lathing to provide a biodegradable escape 

 panel. The top entrance funnel has adjustable 

 panels and is 20 cm x 25 cm in the most open 

 position, as fished throughout the study. Two 

 strips of poured concrete in each end of the trap 

 provided ballast, making the total weight of the 

 trap about 22.7 kg. 



Traps were baited with 1.2-1.6 kg of clupeids. 

 Three Florida and three Fathoms Plus traps were 

 alternately attached at 61 m intervals to 365.6 m 

 of groundline. The groundline was constructed of 

 8 mm diameter Iceline, a dacron, polyethylene 

 line that has a high tensile strength relative to its 

 diameter. A small weight consisting of —9.0 kg of 

 chain was attached to one end of the groundline 

 and an anchor ( -25 kg) was attached to the buoy- 

 line end of the gear. Buoy lines were 366 m sec- 

 tions of 8 mm Iceline joined together to achieve at 

 least a 2:1 ratio of line to water depth. Four inflat- 

 able net buoys and a spar buoy with radar reflec- 

 tor were attached to the buoyline. 



Six depth strata were sampled between lat. 

 29°53.1'-32°20.0'N and long. 78°01.5'-79°24.8'W: 



274-366 m (stratum 1), 367-457 m (stratum 2), 

 458-549 m (stratum 3), 550-640 m (stratum 4), 

 641-732 m (stratum 5), and 733-823 m (stratum 

 6). Three sets of six traps each were made approx- 

 imately 1-2 km apart within a depth stratum over 

 a 24-h period. Sampling locations for each set 

 were selected by making fathometer transects of 

 the potential fishing area to determine depth and 

 bottom type. Because of bad weather and logisti- 

 cal constraints all strata did not receive equal 

 effort (Table 1). 



The first trap type on the groundline was ran- 

 domly selected with trap type alternating until 

 six traps (three of each type) were attached. The 

 exception to this arrangement occurred in the 

 deepest stratum (733-823 m) where only the 

 Fathoms Plus trap was used. 



Fishing duration was standardized at 20 hours; 

 however, poor weather conditions and logistical 

 considerations altered this. Average fishing du- 

 ration within strata exceeded 17 hours (Table 

 1). 



Bottom temperature was determined in each 

 depth stratum by reversing thermometers. Bot- 

 tom sediments were sampled by a geological 

 rocket gi'ab for each group of three sets made in 

 an area. Sediments retrieved were frozen on 

 board and examined under a microscope for gross 

 characterization in the laboratory. Sampling 

 depth and location were recorded at deployment 

 of the anchor. 



Decapod crustaceans in each trap were identi- 

 fied, counted, and weighed. Catches from dam- 

 aged traps or those sets that moved due to cur- 

 rents were excluded from analyses of distribution 

 and abundance, but were included in biological 

 studies of size and sex composition. Each golden 

 crab was individually sexed, measured to the 

 nearest millimeter (carapace width, CW, distance 

 between the tips of the fifth lateral spines; cara- 

 pace length, CL, distance from the diastema be- 



Table 1. — Mean, standard deviation, mini- 

 mum, and maximum fishing duration of trap 

 sets, for Geryon fenneri, within six strata sam- 

 pled from August 1985 to March 1986. 



'Reference to trade names does not inply endorsement by the 

 National Marine Fisheries Service, NOAA. 



548 



