Reproductive biology of the spiny lobster, Panulirus Penicillatus, in the southeastern coastal waters off Taiwan
Published: 2007
Abstract:
Chang, Y. J., Sun, C. L., Chen, Y., Yeh, S. Z., & Chiang, W. C. (2007). Reproductive biology of the spiny lobster, Panulirus Penicillatus, in the southeastern coastal waters off Taiwan. Marine Biology, 151(2), 553-564.
The reproductive biology of spiny lobster, Panulirus penicillatus, was studied based on 2,068 lobsters, ranging from 34.28 to 131.60mm carapace length (CL), sampled in Taitung coastal waters from September 2003 to December 2004. The overall sex ratio approximated 1:1 (χ2=0.02, P>0.05), but the monthly sex ratios in 2004 showed significant differences and males were predominant in sizes larger than 80mmCL. Reproductive activity, assessed using histology, a gonadosomatic index and percentage of ovigerous females, indicated
that the mature females could be found in every month and that the major spawning occurred from May to September. The presence of re-developing/re-ripe ovaries by month and size-specific spawning time suggest that larger mature females (>60mmCL) spawn at least three times a year while smaller new mature females spawn at least once a year. For females, the estimated sizes at 50% physiological and functional maturity were (mean±SE) 56.46±0.56mmCL and 66.63±1.07mmCL. The estimated sizes at functional maturity were between 72 and 74mmCL for males. The number of eggs per spawning event (brood size, BS) was related to CL by the equation YBS=2.4×10-3CL4.18 (r2=0.902, n=12). Female lobsters with CL ranging from 60 to 80mm made the greatest contributions to egg production because of their high brood size and active reproductive activity. A minimum legal size should be established for the fishery to protect egg production potential of lobster population in the southeastern coastal waters off Taiwan.