Determination of the Spawning Season of Bigmouth Sleeper in Puerto Rico by Examination of Gonad Maturation and Reproductive Hormone Cycles
Bigmouth sleepers, Gobiomorus dormitor, are diadromous fish that have potential for hatchery production as both food and sport fish and for conservation purposes. Understanding of bigmouth sleeper maturation and seasonal hormone cycling are necessary in order to realize hatchery production. Therefore, seasonal trends in gonadosomatic index (GSI) and plasma vitellogenin, estradiol, progesterone and total testosterone concentrations were examined in wild and captive populations in Puerto Rico during the presumed spawning season. The spawning season for wild river populations of bigmouth sleepers was protracted over several months, but peaks in male testosterone (6.5 ng/mL) and female vitellogenin (11.3 ng/mL), estradiol (3.3 ng/mL), and GSI (9.5—12.0%) demonstrated that the bigmouth sleeper spawning season occurred primarily in July and August in southwestern Puerto Rico. Captive female broodstock held in shallow hatchery ponds demonstrated accelerated maturation, presumably due to warmer water temperatures in the ponds. Therefore, induced and natural spawning attempts using captive female bigmouth sleeper broodstock should be conducted from June through July. However, advanced gonadal maturation and increased testosterone production in captive males was minimal. Hence, induced spawning for captive rearing purposes should use wild broodstock captured during the peak of the natural spawning season in July and August.
Harris, N. J., J. Neal, T. D. Sink and P. W. Perschbacher.
Determination of the Spawning Season of Bigmouth Sleeper in Puerto Rico by Examination of Gonad Maturation and Reproductive Hormone Cycles.
Gulf and Caribbean Research
Retrieved from http://aquila.usm.edu/gcr/vol24/iss1/6