The effect of male size and spermatophore characteristics on reproduction in the caribbean spiny lobster, panulirus argus
Conference
Butler, MJ, Heisig-Mitchell, JS, Macdiarmid, AB et al. (2011). The effect of male size and spermatophore characteristics on reproduction in the caribbean spiny lobster, panulirus argus
. 15 69-84.
Butler, MJ, Heisig-Mitchell, JS, Macdiarmid, AB et al. (2011). The effect of male size and spermatophore characteristics on reproduction in the caribbean spiny lobster, panulirus argus
. 15 69-84.
The average size of spiny lobsters (Decapoda; Palinuridae) has decreased dramatically worldwide as a result of the over-fishing of large individuals. Average male size is usually diminished more than that of females because of sexual dimorphism and this can impact reproductive success through sperm limitation. Using laboratory mating experiments and field comparisons of fished and unfished populations, we studied differences in spermatophore characteristics that may influence reproductive success in the Caribbean spiny lobster, Panulirus argus, in the Florida Keys, Florida (U.S.A.). We found that large males produce larger spermatophores with more sperm, resulting in operational sperm:egg ratios (range: 21-37:1) that were 40% lower in fished areas. Our experiments show that female mating receptivity is suspended upon receipt of a spermatophore and that this behavior is controlled by a combination of chemical and physical stimuli provided by the spermatophore. The distribution of sperm within spermatophores indicates that the fertilization of multiple clutches from one spermatophore is unlikely, as confirmed by laboratory observations. These results highlight the importance of spermatophore characteristics on fertilization success in spiny lobsters and suggest that reduced male size in the wild may limit reproductive success.
