Applications of Life Table Response Experiments to the Evaluation of Toxicant Effects at the Population Level with the Polychaete Dinophilus gyrociliatus

Heavy metals are among the most widespread pollutants in harbor environments andcoastal habitats subject to anthropogenic impact, and their harmful effects have beendemonstrated on various species of polychaetes, depending on the metal and its rolein physiological processes (Reish and Gerlinger, 1997; Reish, 1998). An evaluation ofthe impact of contaminants at both individual and population levels can be obtainedthrough life table response experiments, a method for estimating the effect of pollutantson biological ' tness (Caswell, 2000). This approach has been recently adopted tostudy the biological effects of pollutants on marine environments utilizing the polychaetesCapitella capitata, Streblospio benedicti, and Dinophilus gyrociliatus as bioindicatorspecies (Levin et a l., 1996; Hansen et a l., 1999; Mauri et al., 2002, 2003).In this chapter, we compare the sensitivity of some population parameters such as thepopulation growth rate, λ, the life expectancy, e0, and the net growth rate, R0, estimatedfor cohorts of D. gyrociliatus exposed to zinc and chromium.