Modeling larval fish behavior: scaling the sublethal effects of methylmercury to population-relevant endpoints.

Expressing the sublethal effects of contaminants measured on individual fish as cohort and population responses would greatly help in their interpretation. Our approach combines laboratory studies with coupled statistical and individual-based models to simulate the effects of methylmercury (MeHg) on Atlantic croaker larval survival and growth. We used results of video-taped laboratory experiments on the effects of MeHg on larval behavioral responses to artificial predatory stimuli.

Maternal body burdens of methylmercury impair survival skills of offspring in Atlantic croaker (Micropogonias undulatus).

Methylmercury (MeHg), the organic form of mercury, bioaccumulates easily through the food chain. Fish in high trophic levels can accumulate substantial levels of MeHg and transfer it to their developing eggs. Here, the effects of maternally derived MeHg on the planktonic larval stage of Atlantic croaker were investigated.

Ecological performance of red drum (Sciaenops ocellatus) larvae exposed to environmental levels of the insecticide malathion.

Malathion is a highly soluble organophosphate insecticide that is widely used in agriculture and mosquito eradication campaigns. Fish species, such as red drum (Sciaenops ocellatus), that use seagrass beds as nursery areas could be affected by runoff waters contaminated with malathion. We exposed red drum larvae at the size they reach in estuarine nursery areas to environmentally realistic and sublethal levels of malathion (0, 1, and 10 microg/L).

Environmental levels of atrazine and its degradation products impair survival skills and growth of red drum larvae.

Red drum larvae (Sciaenops ocellatus) were exposed to environmentally realistic and sublethal levels of the herbicide atrazine (2-chloro-4-ethylamin-6-isopropylamino-S-triazine) to evaluate its effects on ecologically critical traits: growth, behavior, survival potential, and resting respiration rate. Settlement size larvae (7 mm total length) were given an acute exposure of atrazine at 0, 40, and 80 microg l(-1) for 4 days. Tests of 96 h survival confirmed that these naturally occurring concentrations were sublethal for red drum larvae.