Department or Program

Environmental Studies


Growth lines annually deposited in the shells of bivalves can serve to estimate growth rate, which are a reflection of environmental conditions, including anthropogenic disturbance, during their life. The freshwater pearl mussel Margaritifera margaritifera reaches ages of 150-200 years, making it an excellent long-term proxy of climate. Samples of M. margaritifera were obtained from the Karpelva watershed, a river in northeast Finnmark, Norway, in the proximity of a Pechenganickel company smelter on the Kola Peninsula in Russia. The growth variability of M. margaritifera was analyzed by averaging the SGI’s of four M. margaritifera samples (EPS=.56) to develop a long-term growth chronology from as early as 1865 to 2012, which was then correlated with environmental parameters with up to a four year lag. No significant correlations were found, yet correlations with environmental variables were overall stronger before 1946. The shells were also tested at two different sites for heavy metals before and after 1946 when the Nickel smelter was established on the Kola Peninsula. Metal concentrations did not significantly differ between time periods or between sites. Concentrations of Fe and Mg, in the case of this study, are the most likely metals to have contributed to a slowed metabolic rate due to interference with Calcium homeostasis. Long-lived adult pearl mussels have been used as a reliable environmental and physiological long-term archive but further assessment regarding its reliability in polluted conditions should be carried out.

Level of Access

Restricted: Embargoed [Bates Community After Expiration]

First Advisor

Will Ambrose

Date of Graduation

Spring 5-2013

Degree Name

Bachelor of Arts

Number of Pages



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