The reproductive biology and residency patterns of over 800 stone crabs (Menippe mercenaria, M. adina, and their hybrid) were examined during an eight month tagging study at artificial, concrete block reefs constructed near intertidal oyster reefs and subtidal seagrass beds in Franklin and Wakulla Co., Florida. Characteristics of adult crabs occurring intertidally in the summer include a male-biased sex ratio (5M: 1F), a prevalence of M. adina and hybrids, a high frequency (71%) of molting males, and low sperm content (nine million) in males. Subtidally in the summer, the adult sex ratio was female-biased (1M: 9F), the Menippe-complex forms occurred at equivalent frequencies, and male sperm content was higher (18 million). In the fall, sex ratios became more uniform in both habitats, the intertidal male molting frequency declined (7%), and male sperm levels increased (19 million sperm). Mating among the Menippe-complex forms appeared random in both habitats. / A test of the effect of precopulatory guarding on sperm production in stone crabs revealed guarding males contained significantly more sperm (90-100 million) than non-guarding males exposed to pre-molt females or pre-molt males (40-50 million sperm). The sperm level for males held with intermolt females (20 to 30 million sperm) was consistent with background sperm levels from the field study. Male sperm number and the amount of sperm transferred to females were positively correlated. / The influence of sexual selection and predation on postcopulatory guarding durations in stone crabs was also examined. Males guarded significantly longer (126 h beyond the female's molt) when another male stone crab was present than when an intermolt female (84 h) or a blue crab (83 h) were present. In predation trials with the longest postcopulatory guarding durations, the females survived the treatment, whereas females were eaten by the blue crabs in the trials with the shortest guarding durations. The cul-de-sac morphology of the female sperm storage organ is such that sperm pre-emption is likely to occur upon multiple inseminations. Sexual selection appears important in maintaining postcopulatory mate guarding in stone crabs. / Source: Dissertation Abstracts International, Volume: 48-12, Section: B, page: 3486. / Thesis (Ph.D.)--The Florida State University, 1987.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76209 |
| Contributors | WILBER, DARA HEMBREE., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 146 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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