REPRODUCTIVE BIOLOGY OF THE FEMALE DEEP-SEA RED CRAB, 

 GERYON QUINQUEDENS, FROM THE CHESAPEAKE BIGHT 1 2 



Paul A. Haefner, Jr. 3 



ABSTRACT 



Collections of the deep-sea red crab, Geryon quinquedens, were made at depths from 270 to 1,300 m in 

 the vicinity of Norfolk Canyon in the northwest Atlantic Ocean in November 1974, September 1975, 

 and January 1976. The gross morphology and histology of ovary development are described. The size 

 range in which relative growth of the abdomen changes is associated with maturation of the vulvae, 

 copulation and insemination, gonad development, and egg extrusion. Females become sexually mature 

 within the intermolt size range 65-75 mm carapace length (80-91 mm carapace width). Most intermolt 

 females s*76 mm carapace length show signs of copulation and insemination, and their ovaries are in 

 intermediate to advanced stages of development. Few females <75 mm are ovigerous. 



Historically the red crab, Geryon quinquedens 

 Smith, has been seldom utilized commercially 

 (Schroeder 1959; McRae 1961). Explorations have 

 established that red crabs can readily be captured 

 by pot or trap fishing in many regions along the 

 eastern United States. The commercial potential 

 of this crab has spurred investigations of the 

 general biology and distribution (Le Loeuff et al. 

 1974; Haefner and Musick 1974; Wigley et al. 

 1975; Gray 4 ; Dias and Machado 5 ; Ganz and 

 Herrmann 6 ) as well as technological and economic 

 aspects of harvesting and processing (Meade and 

 Gray 1973; Holmsen and McAllister 1974). 



The present study was prompted by recognition 

 that biological data on sexual maturity are re- 

 quired for proper management of red crab stocks. 

 This paper presents data on collections from 

 Chesapeake Bight and deals with various aspects 

 of reproductive biology of the female crab: ovary 

 development, size composition of catch, size of 



'Research cruises supported by National Science Foundation 

 Grant GA-37561, J. A. Musick, principal investigator, and by the 

 University of Virginia Institutional Grant Program for P. A. H. 

 participation. 



Contribution No. 777, Virginia Institute of Marine Science, 

 Gloucester Point, VA 23062. 



'Virginia Institute of Marine Science, Gloucester Point, VA 

 23062. 



"Gray, G. W., Jr. 1969. Investigation of the basic life history of 

 the red crab (Geryon quinquedens). R.I. Div. Conserv. P.L. 88- 

 309, Proj. 3-46-R Completion Rep., 36 p. 



5 Dias, C. A., and J. S. Machado. 1974. Preliminary report on 

 the distribution and relative abundance of deep-sea red crab 

 (Geryon sp.) off Angola. Sci. Pap. No. 26, 12 p. In Scientific papers 

 presented to the second session of the International Commission 

 for the Southeast Atlantic Fisheries (Madrid, December 1973). 

 Publ. Mimeogr. M. E. Bioceanol. Pescas, Angola 12, 75 p. 



6 Ganz, A. R., and J. F. Herrmann. 1975. Investigations into 

 the southern New England red crab fishery. R.I. Dep. Nat. 

 Resour. Div. Fish. Wildl. Mar. Fish. Sect., 78 p. 



ovigerous individuals, abdomen width-carapace 

 length relationship, development of vulvae, and 

 evidence of copulation and insemination. 



METHODS 



Red crabs were collected at depths from 270 to 

 1,300 m in Norfolk Canyon and vicinity (lat. 

 36°32'-37°10'N; long. 74°10'-74°46'W) in Novem- 

 ber 1974 (RV James M. Gilliss 74-04), September 



1975 (RV James M. Gilliss 75-08), and January 



1976 (RV James M. Gilliss 76-01). Based on the 

 recommendations of Gray (see footnote 4), all 

 female crabs were measured for short carapace 

 length (CL, distance from the diastema between 

 the rostral teeth to the posterior edge of the 

 carapace, along the midline); width of the fifth 

 abdominal segment was recorded for 190 crabs. 

 Carapace length may be converted into carapace 

 width (CW) by using the equation CW = 11.04 + 

 1.06CL, r = 0.98, based on measurements of 268 

 female crabs. 



Pleopods and vulvae were examined to deter- 

 mine if mating and egg extrusion had occurred. 

 Eggs or egg remnants or their absence on 

 pleopods, variations in the size, shape and physi- 

 cal condition of vulvae, and the relative size of 

 seminal receptacles were noted. Selected samples 

 of the spermathecal fluid were withdrawn directly 

 from incisions in the receptacle and examined mi- 

 croscopically for presence of sperm or spermato- 

 phores. 



Ovaries were initially classified to relative size 

 following the scheme used for the rock crab, 

 Cancer irroratus (Haefner 1976). The scheme for 



Manuscript accepted June 1976. 



FISHERY BULLETIN: VOL. 75, NO. 1, 1977. 



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