INFLUENCE OF DELAYED METAMORPHOSIS ON SURVIVAL, GROWTH, AND REPRODUCTION OF THE MARINE POLYCHAETE CAPITELLA-SP-I

In the absence of an appropriate environmental cue, larvae of benthic marine invertebrates typically delay their metamorphosis. Delaying metamorphosis is considered beneficial in promoting placement of offspring into suitable habitats and likely increasing genetic exchange among populations. However, recent studies suggest that delaying metamorphosis can reduce juvenile fitness in some species, by reducing postmetamorphic survivorship or growth rate. The effects of delayed metamorphosis on survival, growth, and reproduction of the marine polychaete Capitella sp. I were tested. The lecithotrophic larvae, which are competent to metamorphose within minutes of their release from the parental brood tube, were forced to delay metamorphosis for up to 216 h at 20-degrees-C. We induced metamorphosis at intervals by adding azoic sediment, and then reared the juveniles in the laboratory for up to 4 wk. Although survival was significantly reduced (P < 0.01) when larvae delayed metamorphosis for > 72 h, delaying metamorphosis had no convincing effect on postmetamorphic growth rate (mu-g tissue.day-1), time to first reproductive activity, or fecundity.