Effect of localized oil spills on Atlantic loggerhead population dynamics
- 1 Department of Mathematics, Oregon State University, Corvallis, USA
- 2 Department of Mathematics, California State University Bakersfield, Bakersfield, USA
- 3 Department of Mathematics, Luther College, Decorah, USA
- 4 Department of Mathematics, Arizona State University, Tempe, USA
- 5 Department of Mathematics, The University of South Dakota, Vermillion, USA
Abstract
The purpose of this study is to analyze the population dynamics of loggerhead sea turtles (Caretta caretta) affected by localized oil spills. Methods include development of a spatial, stage-classified matrix model parameterized for the following primary loggerhead populations: Gulf of Mexico, western North Atlantic Ocean, and Florida peninsula. Oil spills are simulated deterministically in each population's nesting region, with 1) oil-induced mortality ranging from 25% to 100% and 2) stage classes affected either proportionally or equally. A transient sensitivity analysis was performed to determine the parameters most influential to the population growth rate. Results suggest that increased protection and understanding of young sea turtles found in the Sargasso Sea is essential to the survival of the species. In addition, findings provide insights into the population dynamics of the At- lantic loggerhead turtles and identify conservation measures appropriate in each oil spill case.
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