by Joe Bartoszek, Ph.D., Resource Contaminant Specialist, Washington Fish and Wildlife Office
The western pearlshell, once abundant in the Hanford Reach of the Columbia River in southeastern Washington, can no longer be found. Although the cause for their disappearance is not known, the long-lived mussel (some individuals have been aged at more than 100 years) may have suffered from releases of contaminants from the Hanford Department of Energy site.
Pearlshell mussel collected from the Eel River, CA. (Photo: Dr. Chris Barnhart)
The Hanford Natural Resource Trustees would like to understand what happened to mussels in the river by testing potential sensitivity to contaminants released from the site, particularly hexavalent chromium (the contaminant made famous in the Erin Brockovich movie).
On an expedition to the Eel River in Northern California, Dr. Jeanette Howard of The Nature Conservancy collected and sent some western pearlshell mussels to Dr. Chris Barnhart at Missouri State University for rearing. With knowledge gained last year, Dr. Barnhart will be able to supply the USGS testing laboratory in Columbia, MO with juvenile western pearlshell mussels for toxicity tests.
In preliminary tests last year, the western pearlshell was found to be slightly less sensitive to hexavalent chromium than the commonly tested freshwater mussel, the fatmucket. The western pearlshell sensitivity to hexavalent chromium seemed to increase at higher temperatures. We hope to learn more details this year in our testing.