Effects of delayed settlement on survival, growth, and reproduction in the spionid polychaete,Polydora ligni

Summary Larvae of the spionid polychaete, Polydora ligni Webster 1879, were forced to delay settlement and metamorphosis for 6 days by withholding suitable substrata. Daily mortality was 2.5% during the competent period of larval development. Starvation increased mortality to 5.4% per day. A high percentage of the control (nondelayed) and fed, delayed larvae metamorphosed (70–81%) and the newly metamorphosed juveniles were the same size in these 2 groups. However, delay combined with starvation greatly reduced metamorphic success (to 15%) and juvenile size. Delay (with feeding) significantly decreased somatic and reproductive growth of post-metamorphic juveniles compared to the nondelayed control group. Costs of delayed settlement and metamorphosis could partially offset the advantages of extending the larval period for benthic habitat selection.