Species sensitivity assessment of petroleum hydrocarbons to six species of Atlantic scleractinian corals Conference Paper uri icon

abstract

  • 2019 Proceedings - 42nd AMOP Technical Seminar on Environmental Contamination and Response. All rights reserved. Coral reefs are keystone coastal ecosystems that are at risk of exposure to petroleum hydrocarbons from a range of sources, including oil spill incidents and chronic runoff, and are usually one of the highest valued natural resources for protection in Net Environmental Benefit Analysis (NEBA)/Spill Impact Mitigation Assessment (SIMA) of response methods and environmental damage. Previous research evaluating hydrocarbon impacts to corals has resulted in no clear characterization of sensitivity, as work has generally focused on higher-level effects, compounded by significant variability in experimental methodology. This represents an important knowledge gap in oil spill preparedness and response as it relates to the potential impact of oil spills to the coral animal and its photosymbiont zooxanthellae. This research was therefore designed to address this gap, using a standardized toxicity testing protocol to evaluate effects of the petroleum/dispersant system on scleractinian corals. The relative sensitivity of six Atlantic scleractinian coral species to hydrocarbon exposure was assessed with 48-h assays using 1-methylnaphthalene, phenanthrene, toluene, and MC252 oil. Effects were evaluated based on physical coral condition, mortality, photosynthetic efficiency, growth rate, and histological condition. The threatened staghorn coral Acropora cervicornis was found to be the most sensitive to single hydrocarbon exposure, and Siderastrea siderea the least sensitive. No mortality or bleaching was observed in Porites divaricata exposed to passively-dosed MC252 oil at 324.1 g/L TPAH, the highest concentration tested. Overall, the acute and subacute endpoints indicate that corals are comparatively more resilient to narcotic chemical exposure than other coastal marine species, possibly due to the lipid-rich nature of coral tissue and their ability to secrete mucus. Thus, these endpoints may be substantially affected by seasonal changes (temperature, light) in coral lipid content. The results of this study provide a framework for the prediction of oil impacts and impact thresholds on the coral animal and related habitats, significantly improving modeling and predictability of the effects of spill responses in coastal tropical environments.

published proceedings

  • Proceedings - 42nd AMOP Technical Seminar on Environmental Contamination and Response

author list (cited authors)

  • Abigail Renegar, D., Turner, N. R., Bera, G., Knap, A., & Schuler, P.

complete list of authors

  • Abigail Renegar, D||Turner, NR||Bera, G||Knap, A||Schuler, P

publication date

  • January 2019