CHANGES IN GRASS SHRIMP POPULATIONS IDENTIFIED AS MEASURING TOOL FOR COASTAL SEDIMENT CONTAMINATION, AND FOR MEASURING ESTUARINE HEALTH

Dec. 29, 2006 — The NOAA National Centers for Coastal Ocean Science announced a direct link between estuarine sediment contaminant levels and grass shrimp populations. The study performed at three sites in coastal South Carolina showed grass shrimp population densities and shrimp size were depressed in areas with the greatest concentrations of contaminants. (Click NOAA image for larger view of male and female grass shrimp. Please credit “NOAA.”)

"Grass shrimp are widely distributed throughout the tidal marsh system and are an
ecologically important species," said Peter Key, research fishery biologist with the NOAA Ocean Service. "These shrimp are important to the health of commercially valued fish and crustaceans and their decline could impact the estuarine food chain."

"This type of basic research is critically important to NOAA and to coastal resource managers in making informed environmental decisions as we seek to promote wise use of our coastal resources," said John H. Dunnigan, director of the NOAA Ocean Service. "One of NOAA's critical missions is to understand and protect these resources."

Surface sediments were collected for the measurement of chemical contamination, and shrimp were collected using push-netting—wide-mouthed nets pushed along the water's edge to catch shrimp—at three known contaminated estuarine tidal creeks, using as a reference point a fourth site that has displayed no history of industrial influence.

Contaminants may enter estuaries through a variety of pathways, including surface
runoff, industrial waste and atmospheric deposits. When estuarine sediment contamination levels become significantly high, negative impacts to estuarine ecosystems, flora and fauna, can occur.

This latest research is part of ongoing research using grass shrimp (Palaemonetes
species) as an indicator of human impacts on estuaries and the coastal environment. Earlier testing coupled with ecological monitoring and biomarkers—indicators of contaminant exposure—identified that this common crustacean may help coastal managers make informed environmental decisions in use as a model indicator species.

"The goal of this research is to use an integrated approach, including chemical contaminant analysis, sediment quality guidelines and grass shrimp population assessments to assess contaminant impacts in estuaries," said Mike Fulton, a NOAA research fishery biologist.

Grass shrimp is widely distributed along the East and Gulf coasts of the United States in tidal marsh systems. These shrimp are ecologically important estuarine crustaceans that are studied from both toxicological and ecological perspectives. Due to its high natural densities and ease of culture in laboratories, Palaemonetes species have become a "sentinel species" in coastal ecosystems research studies.

In 2007 NOAA, an agency of the U.S. Commerce Department, celebrates 200 years of science and service to the nation. Starting with the establishment of the U.S. Coast and Geodetic Survey in 1807 by Thomas Jefferson much of America's scientific heritage is rooted in NOAA. The agency is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and information service delivery for transportation, and by providing environmental stewardship of the nation's coastal and marine resources. Through the emerging Global Earth Observation System of Systems (GEOSS), NOAA is working with its federal partners, more than 60 countries and the European Commission to develop a global monitoring network that is as integrated as the planet it observes, predicts and protects.

Relevant Web Sites
NOAA National Centers for Coastal Ocean Science

NOAA Ocean Portal

Media Contact:
Daniel Parry, NOAA Ocean Service, (301) 713-3066