Meeting Abstract

88.1  Friday, Jan. 7  Multiple Mating and Sperm Allocation in an Exploited Decapod Crustacean WELLS, S.L.*; MCCONAUGHA, J.R.; HORTH, L.A.; Old Dominion University; Old Dominion University; Old Dominion University swells@odu.edu

The Chesapeake Bay ecosystem has suffered in recent years due to pollution, overharvesting of resources, and habitat destruction. The blue crab, Callinectes sapidus, population suffered severe fishing mortality (>60%/yr) which resulted in changes in population structure and density for this species. Male and female crabs have modified their reproductive investment, allocation, and behavior in recent years, likely in response to the population changes. Male crab number and size have decreased in the Bay population resulting in a reduction in the amount of sperm produced as well as an increase in the number of encounters with females. The number of sperm transferred to a female in this study was found to vary between females, with order of magnitude differences detected in some cases. There were also significant differences in sperm number when comparing the left and right spermathecae within some individual females. Microsatellite DNA analysis from this study demonstrated that the majority of females sampled have mated with more than one male. Genetic data indicated that there were differences in male donors between right and left spermathecae. In some cases one spermathecae had a single male’s sperm while the other spermathecae had contributions from multiple males. This suggests that there are differences in sperm allocation to individual females which were previously unknown and requires further investigation. The differences observed in sperm allocation, may affect paternity but the exact effects are unknown. Unequal sperm allocation from males has the potential to change the genetic diversity of the population.