title: Simulating the effects of fluctuating dissolved oxygen on growth, reproduction, and survival of fish and shrimp.
abstract: Individuals are commonly exposed to fluctuating levels of stressors, while most laboratory experiments focus on constant exposures. We develop and test a mathematical model for predicting the effects of low dissolved oxygen (hypoxia) on growth, reproduction, and survival using laboratory experiments on fish and shrimp. The exposure-effects model simulates the hourly reductions in growth and survival, and the reduction in reproduction (fecundity) at times of spawning, of an individual as it is exposed to constant or hourly fluctuating dissolved oxygen (DO) concentrations. The model was applied to seven experiments involving fish and shrimp that included constant and fluctuating DO exposures, with constant exposures used for parameter estimation and the model then used to simulate the growth, reproduction, and survival in the fluctuating treatments. Cumulative effects on growth, reproduction, and survival were predicted well by the model, but the model did not replay the observed episodic low survival days. Further investigation should involve the role of acclimation, possible inclusion of repair effects in reproduction and survival, and the sensitivity of model predictions to the shape of the immediate effects function. Additional testing of the model with other taxa, different patterns of fluctuating exposures, and different stressors is needed to determine the model's generality and robustness.
authors.affiliation: Duquesne University, Department of Mathematics and Computer Science, 440 College Hall, 600 Forbes Avenue, Pittsburgh, PA 15219, United States. Electronic address: neilan@mathcs.duq.edu.
authors.forename: Rachael
authors.initials: R
authors.lastname: Miller Neilan
authors.affiliation: 2135 Energy, Coast and Environment Building, Department of Oceanography and Coastal Science, Louisiana State University, Baton Rouge, LA 70803, United States.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Rose
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002138:Calibration; D003198:Computer Simulation; D033364:Decapoda / Q000187:drug effects / Q000254:growth & development*; D005298:Fertility / Q000187:drug effects; D005399:Fishes / Q000254:growth & development*; D008954:Models, Biological; D010100:Oxygen / Q000494:pharmacology*; D012098:Reproduction / Q000187:drug effects*; D012995:Solubility; D016019:Survival Analysis
chemical_list: D010100:Oxygen
keywords: Exposure-effects; Hypoxia; Intermittent; Model