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Different modes of reproduction were examined in the context of entire life cycles for seven starfish species so that adult survival could be compared with reproductive output and first year survival. Data were assembled from the literature and included two asexual species, Linckia multifora and Nepanthia belcheri; two brooders, Asterina phylactica acid Leptasterias hexactis; one species with benthic eggs that does not brood, Asterina gibbosa; one species with lecithotrophic development in the plankton, Patiriella pseudoexigua; and one planktotrophic species, Pisaster ochraceus. A negative correlation was found between first-year survival and adult survival rates which also correlated with mode of reproduction: highest adult survival and lowest first-year survival was found for P. ochraceus, the planktotrophic species, and lowest adult survival was coupled with highest first-year survival in asexual species. A matrix model was developed to explore the metapopulation consequences of different modes of reproduction. Asexual species are similar to species with planktonic larvae that also have long-lived adults in that both are well insulated from the vagaries of planktonic life, one by avoiding the plankton all together and the other by having very low transition probabilities for the first year of life but high transition probabilities for retention of adults in the population. Species with short-lived adults and planktonic development of larvae are more closely tied to changes in first-year survival rates with respect to over-all dynamics of metapopulations. |
