Influence of Age-Specific Mortality on the Life History Traits of Two Estuarine Copepods

Abstract

Llfe history traits -including day of first reproduction, lifetime reproductive output, and total lifespanwere determined in the laboratory for 2 estuarine copepods: Scottolana canadensis (Willey) and O~thona colcarva Bowman. The day of first reproduction was earlier for 0. colcarva than for S. canadensis, but the latter had a much longer reproductive lifespan and a greater reproductive output in terms of nauplii produced per female. The copepods exhibited intrinsic rates of increase ranging from 0.01-0.19 d-' for 0. colcarva (15"-25 "C) and 0.05-0.15 d ' for S. canadensis (20"-25 "C).