Observations on the life cycle of Procambarus acutus acutus in South Carolina culture ponds
2004
Procambarus acutus acutus population structure and reproductive development was evaluated during the dry-culture (Aug¡Sep) and the wet-culture phases (Nov-Jun) in 0.1-ha culture ponds. Two cohorts of crayfish, carryover (CO) crayfish and young-of-the-year (YOY) crayfish were present in the ponds. Young-of-the year crayfish grew throughout the 233-day wet-culture phase, averaging 0.19-mm total length (TL)/day, while CO crayfish growth occurred only during 3 of the 8-monthly sampling periods. The fastest growth occurred in fall (Nov-Dec) and spring (Apr-May) for YOY, and in March for CO crayfish. Form-I males were present in each of the wet- and dry-culture samples. Females excavated from burrows during the dry-culture phase possessed significantly greater gonadosomatic indices (GSIs) and less hepatopancreas moisture (HM) than females sampled during the wet-culture phase. Larger females, designated as CO individuals, burrowed earlier and exhibited more advanced gonad development than the smaller YOY females. Individuals of both designated cohorts oviposited eggs; however, attached young were observed only on the excavated CO crayfish. Pleopod eggs per female increased linearly with crayfish TL; however, those crayfish held in cups in the laboratory oviposited significantly more eggs than the females excavated from burrows. Crayfish held in cups oviposited 96% of the eggs in their ovaries. The life cycle traits of P. a. acutus limit the harvest to one recruitment wave in South Carolina culture ponds.
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