Improving Mussel Monitoring

Mussels collected from a nearshore monitoring plot.

NPS/Jim Pfeiffenberger

Alaska has tens of thousands of miles of coastline that are only accessible by boat or plane and only during short periods of the summer due to remoteness and weather conditions. Recognizing that change is inevitable, technologies for monitoring the status of nearshore marine ecosystems in remote areas are necessary for managing and maintaining healthy coastal communities. One approach for assessing ecosystem status is the use of indicator species, including intertidal bivalves (e.g., mussels). Bay mussels (Mytilus trossulus) are ubiquitous throughout nearshore communities in the Gulf of Alaska and northeast Pacific and are a primary food source for marine and terrestrial predators. Changes in bay mussel populations due to abiotic or biotic factors may result in alterations of the entire intertidal community structure.

In recent years, there have been major advances in assays to evaluate the physiological condition of mussels using biomarkers (biological metrics that quantify a physiological response including detection of proteins or their activity) and gene transcription (measurement of alterations in transcription of specific genes) to elucidate changes at the molecular level in response to environmental changes and contaminant exposure. The goal of this study was to work toward an approach that combines biomarker and genetic methods to assess the condition of nearshore ecosystems, including those in areas that are remote and logistically difficult to access.

Physiological and gene transcription assays to assess responses of mussels to environmental changes

Abstract

Coastal regions worldwide face increasing management concerns due to natural and anthropogenic forces that have the potential to significantly degrade nearshore marine resources. The goal of our study was to develop and test a monitoring strategy for nearshore marine ecosystems in remote areas that are not readily accessible for sampling. Mussel species have been used extensively to assess ecosystem vulnerability to multiple, interacting stressors. We sampled bay mussels (Mytilus trossulus) in 2015 and 2016 from six intertidal sites in Lake Clark and Katmai national parks and preserves, in south-central Alaska. Reference ranges for physiological assays and gene transcription were determined for use in future assessment efforts. Both techniques identified differences among sites, suggesting influences of both large-scale and local environmental factors and underscoring the value of this combined approach to ecosystem health monitoring.

Counihan, K., L. Bowen, B. Ballachey, H. Coletti, T. Hollmen, B. Pister, and T. L. Wilson. 2019. Physiological and gene transcription assays to assess responses of mussels to environmental changes. PeerJ 7:e7800 https://doi.org/10.7717/peerj.7800