Investigating the effect of oil spills
on the environment and public health.
revert menu
Funding Source: Year One Block Grant - The Alabama Marine Environmental Science Consortium

Project Overview

Assessing the Impact of the Deepwater Horizon Oil Spill on the Diamondback Terrapin: a Top Carnivore and Keystone Species in the Salt Marshes of Alabama

Principal Investigator
University of Alabama at Birmingham
Department of Biology
Member Institutions
Dauphin Island Sea Lab (DISL), University of Alabama at Birmingham, University of South Alabama


The diamondback terrapin (Malaclemys terrapin) is a top carnivore and keystone species in salt marsh habitats throughout areas of the northern Gulf of Mexico that were impacted by the Deepwater Horizon Oil Spill.  Due to their ecology and physiology, the diamondback terrapin represents an optimal model for documenting the impact of oil contamination on a higher trophic level predator in the salt marsh.  Specifically, they have a limited home range, typically remaining localized in a particular salt marsh, are long-lived, slow growing, and have relatively low reproductive rates. 

Therefore, terrapin populations are extremely sensitive to small decreases in adult and juvenile survival, such as those that could result from oil pollution. Terrapins also consume prey that accumulate PAHs and they metabolize PAHs at a rate that is approximately 10% of the levels reported in birds, mammals, and fish. We have the best documented population of diamondback terrapin in the Gulf of Mexico.  This includes a multi-year database on reproductive output and a multi-year repository of blood and tissue samples which can be analyzed for PAH’s and stress hormones (e.g. corticosteroids). 

During the current project we will evaluate the effects of Deepwater Horizon Oil Spill on the diamondback terrapin in the salt marshes of Alabama by conducting:

1. Range wide surveys of diamondback terrapin in order to obtain blood and tissue samples for PAH analysis and stress hormone analysis

2. Conducting a comprehensive mark-recapture population studies and intensive nesting beach surveys to determine post-oil spill survival and reproductive rates

This research was made possible by a grant from BP/The Gulf of Mexico Research Initiative.