Meeting Abstract
Larval cloning has been observed in a variety of species of marine invertebrates, but is perhaps best known in echinoderms. Larvae have been noted to clone through a variety of processes and under many different conditions, but the inductive cues for cloning are largely unknown. Prior work suggests that both increases in food availability and the presence of predator cues could be contributing factors to larval cloning. In this project, we examined the effects of food, temperature, and salinity on the frequency of cloning in the larvae of Pisaster ochraceus. We also tested the impacts of predator cues from larval crabs and planktivorous fish on the frequency of cloning in larval P. ochraceus, Dendraster excentricus, Strongylocentrotus purpuratus, and Evasterias troschelii. Food, temperature, and predator cues had little effect on the frequency of cloning in any species. While there were few effects of predator cues on larval cloning, larvae exposed to crab megalopae were smaller in size than those of the control or fish treatment groups. Additionally, in P. ochraceus there was a salinity effect detected, where larvae exposed to lower salinity levels exhibited more frequent cloning. In addition, the clones of P. ochraceus were tracked to determine regeneration time and mortality of different clone types. These results contrast with other studies that have demonstrated an impact of both food availability and predator cues on larval cloning and suggest that other environmental factors, such as salinity, may play a role in inducing cloning in some species. The ultimate effects of larval cloning on recruitment of individuals into a population are largely unknown for any species, but in the future, we plan to test the consequences of cloning on survival and recruitment of larvae and juveniles.
