Reproductive Biology of the Blue Crab, Callinectes amnicola (De Rocheburne) in the Lagos Lagoon, Nigeria

Nijerya’nın Lagos Gölü’ndeki Callinectes amnicola’nın (De Rocheburne) cinsiyet oranı, fakondite, olgunlaşma gelişimi ve oogenezi araştırılmıştır. Erkek/dişi oranı 1:0,96’dır. Fekondite, 478.400 ile 4.480.500 yumurta arasında tahmin edilmiş olup ortalama, 780.480 yumurtadır. Yumurtaların çapı 0,25 ile 0,35 mm arasında değişmektedir ve ortalama çap 0,29 mm’dir. Yengecin fekonditesi ve ağırlığı (r = 0,247) arasında düşük pozitif korelasyon görülmüştür. Olgunluk, dişiler için 6,2 ve 16,5 cm karapas genişliği arasında elde edilmiş olup, bu değer erkekler için 7,3 ve 15,3 cm karapas genişliğindedir. Yüzde elli olgunluk ($TL_ {50}$) erkeklerde 10,8 cm, dişilerde ise 11,0 cm karapas genişliğinde elde edilmiştir. Gonadlar için beş olgunluk aşaması tespit edilmiştir. Oositler için üç temel gelişimsel aşama gözlenmiştir. Olgun ve olgunlaşmamış yengeçler yıl boyunca gölden elde edilmiş ve böylelikle bu türün mart ve haziran arasında pik yaparak ürediğine işaret etmiştir.

Anahtar Kelimeler:

Nigeria, üreme, doku bilimi, eşeylik organları, kıyı gölü, gelişme dönemleri, eşey oranı, döllenme gücü

Lagos Lagünündeki (Nijerya) Mavi Yengeçlerin, Callinectes amnicola (De Rocheburne) üreme biyolojisi

Sex ratio, fecundity, maturation development and oogenesis of Callinectes amnicola (De Rocheburne) in the Lagos Lagoon, Nigeria were investigated. The male/female ratio was 1:0.96. Fecundity estimates ranged between 478,400 and 4,480,500 eggs with a mean of 780,480 eggs. The diameter of the eggs varied between 0.25 and 0.35 mm with a mean of eggs 0.29 mm. A low positive correlation existed between fecundity and weight (r = 0.247) of the crab. Maturity was attained between 6.2 and 16.5 cm carapace width (CW) for the females and between 7.3 and 15.3 cm CW for the males. Fifty percent maturity ($TL_ {50}$) was attained at 10.8 cm CW in the males and 11.0 cm CW in the females. Five maturity stages of gonads were identified. Three major developmental stages of oocytes were observed. Immature and mature crabs were obtained in the lagoon throughout the year indicating that this species breeds throughout the year with a peak between March and June.

Keywords:

Nigeria, reproduction, histology, gonads, lagoons, developmental stages, sex ratio, fecundity,

PDF

___

Bagenal, T.B. 1978. Aspect of fish fecundity. In: S.D. Gerking, (Ed.), Method of Assessment of Ecology of Freshwater Fish Production, Blackwell Scientific Publications, Blackwell, Oxford: 75-101.
Campbell, A. and Eagle, M.D. 1983. Size at maturity and fecundity of rock crabs, Cancer irroratus from the Bay of Fundy and south western Nova Scotia. Fisheries Bulletin, 81: 352-362.
Chindah, A.C., Tawari, C.C. and Ifechukwude, K.A. 2000. The food and feeding habits of the swimming crab, Callinectes amnicola (Portunidae) of the New Calabar River, Nigeria. Journal of Applied Science and Environmental Management, 4: 51-57.
Ezenwa, B.I.O. and Kusemiju, K. 1985. Seasonal changes in the gonads of the catfish Chrysichthys nigrodigitatus (Lacepede) in Badagry Lagoon, Nigeria. Biologia Africana, 2: 15-23.
Guillory, V. and Hein, S. 1997. Sexual maturity in blue crabs, Callinectes sapidus. Proceeding of Coastal Fishing, Louisiana’s Blue Crab Resource La. St. University Academy of Science, 59: 5–7.
Guillory, V., Prejean, E., Bourgeois, M., Burdon, J. and Merrell, J. 1996. A biological and fisheries profile of the blue crab, Callinectes sapidus. LA. Department of Wildlife and Fisheries Management Plan Series, 8 (1): 210 pp.
Hankin, D.G., Diamond, N., Mohr, M. and Lanelli, J. 1985. Molt increments, annual molting probabilities, fecundity and survival rates of adult female Dungeness crabs in northern California. In: Proceedings of the symposium on Dungeness crab biology and management, Lowell Wakefield Fish Symp. Ser. Alaska Sea Grant Rep. Fairbank: 85–88.
Hartnoll, R.G. 1985. Growth, sexual maturity and reproductive output. In: A.M. Wenner (Ed.), Factors in adult growth, Crustacean Issues, Rotterdam: Balkema, 3: 101–128.
Hines, A.H. 1982. Allometric constraints and variables of reproductive efforts in brachyuran crabs. Marine Biology, 69: 309-320
Kwei, E.A. 1978. Size composition, growth and sexual maturity of Callinectes latimanus (Rath) in two Ghanaian lagoons. Zoological Journal of the Linnaean Society, 64 (2): 151–157.
Lawal-Are, A.O. and Kusemiju, K. 2000. Size composition, growth pattern and feeding habits of the blue crab, Callinectes amnicola (De Rocheburne) in the Badagry Lagoon, Nigeria. Journal of Science Research and Development, 5: 169-176.
Marcus, O. and Kusemiju, K. 1984. Some aspects of the reproductive biology of the clupeid Ilisha africana (Bloch) off the Lagos coast, Nigeria. Journal of Fish Biology, 25(6): 679-689.
Millikin, M.R. 1979. Blue crab larval culture: methods and management. Marine Fisheries Review, 40(11): 10- 17.
Nedelec, C. 1982. Definition and classification of fishing gear categories. FAO Fish Technical Paper, No 222: Rome, 57 pp.
Nikolsky, G.V. 1963. The ecology of fishes. Academic Press, London and New York.
Ofori- Danson, P.K. 1990. Reproductive ecology of the trigger fish, Ballistes capriscus from the Ghanianain coastal waters. Tropical Ecology, 31 (1): 1–11.
Parsons, R. 1988. Statistical analysis. A decision – making approach. Second edition, Harper and Row Publishers, New York.
Shields, J.D. 1992. The reproductive, ecology and fecundity of Cancer crabs. In: A.M. Wenner and A.M. Kurts (Eds.), Crustacean egg production. Crustacean issues 7. Balkema, Rotterdam
Shields, J.D. Okazaki, R.K. and Kurts, A.M. 1990. Fecundity and the Reproductive Potential of the Yellow Rock Crab Cancer anthonyi. Fishery Bulletin, US, 89: 299-305
Solarin, B.B., Udolisa, R.E., Omotoyo, N.O., Lebo, P.E. and Ambrose, E. 2003. Hook, line and sinker - The small scale fishing gear in Nigeria. ICSF Chennai, India / Brussels, Belgium. Samudra, 35: 41–46.
Van-Montfrans, J., Epifanio, C.E., Knott, D.M., Lipcius, R.N., Mense, D.J., Metcalf, K.S., Olmi III, E.J., Orth, R.J., Posey, M.H., Wenner, E.L. and West, T.L. 1995. Settlement of blue crab megalopae in western Atlantic estuaries. Bulletin Marine Science, 57(3): 834-854.