Mussel Watch represents the longest running continuous contaminant monitoring program in U.S. coastal and Great Lakes waters and was created in response to concerns over environmental quality of the Nation's coastal and estuarine ecosystems. This project analyzes chemical and biological contaminant trends in sediment and bivalve tissue collected at over 280 coastal sites from 1986 to present. Parameters monitored include sediment and bivalve tissue chemistry for over 100 organic and inorganic contaminants; bivalve histology; and Clostridium perfringens (pathogen) concentrations. This project regularly quantifies PAHs, PCBs, chlorinated pesticides including DDT and its metabolites, TBT and its metabolites, and trace elements.

These data represent environmental DNA detections of freshwater mussels in the Green River, KY, USA; West Virginia long-term water quality monitoring sites, USA; and the Chesapeake Bay and Potomac basin, Maryland, USA. “This research dataset has been reviewed in accordance with U.S. Environmental Protection Agency (U.S. EPA), Office of Research and Development, and approved for release. Mention of brand names or vendors does not constitute an endorsement of products or services by the U.S. EPA.”"

This collection contains 1986-1989 Mussel Watch Data collected under National Status and Trends Program. The samples were collected along the east, west, gulf coast of the United States and two sites in Hawaii. Bivalve samples were analyzed for the presence of the following contaminants: polyaromatic hydrocarbons (PAH's), total DDT's and total chlorinated pesticides, and for trace metal concentrations. There are data from three phases of study, which were analyzed by Battelle Ocean Sciences. Data ranges for the three phases are: Phase 1 contains data for 288 bivalves from 96 locations; 01/07/86-05/13/86. Phase 2 contains data for 297 bivalves collected at 99 locations; 11/11/86-03/28/87. Phase 3 contains data for 321 bivalves from 107 locations; 11/20/87-03/29/88. Bivalve data also includes species, shell length, and gonadal indices. Bivalve data associated with this study (Phases 1-3) is located on the 0-data/ directory under folder number L00434.dir. Folder number L01130.dir contains the Benthic Surveillance Program Data for 1984 thru 1986. This program determines the toxic concentrations in sediments and bottom fish. Samples were collected in the same sites as described above. Sediments were analyzed for the presence of the following contaminants: polyaromatic hydrocarbons (PAH's), total DDT's and total chlorinated pesticides, and for trace metal concentrations. The Benthic sediment/fish data were collected concurrently with bivalve samples. However, Benthic data were only available from Battelle Ocean Sciences for Phase 1 (259 sediments at 87 locations from 01/15/86 - 05/14/86) and Phase 2 (232 sediments at 72 locations from 11/11/86 - 03/28/87) at the time of this submission.

This data release includes the data associated with the manuscript "Freshwater mussel distribution and catchment prioritization for mussel conservation in the Northeastern United States." It describes native freshwater mussel distribution data for Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut as well as catchment priority scores for different conservation activities. The data release also includes some data to enable better understanding of the models used in the associated manuscript such as model standard deviations and model parameter permutation importance values.

The Minnesota Department of Natural Resources (MNDNR) has been quantitatively sampling a mussel bed in West Newton Chute (a side channel in Navigation Pool 5 of the Upper Mississippi River, UMR) annually since 2008. Briefly, ~200 systematically-placed 0.25 m2 quads are sampled annually; divers excavate substrates to a depth of ~15 cm and place material into a 6 mm mesh bag. Mussels are identified to species, aged via external annuli, measured for shell length, and sexed. From 2008-2016, this mussel bed contained 12-16 live species, had densities that ranged from 4-10/m2, and juveniles (≤ 5 years old) comprised 3-18% of the assemblage. Because this assemblage was well characterized, it represented an excellent location to estimate vital rates (i.e., survival and growth) in mussels. Our objectives were to estimate patterns in survival and growth across four species of mussels and over time within a mussel bed, and to assess if these patterns changed across patches with varying mussel densities. The counts of live mussels in quadrats sampled by the MNDNR during surveys from 2008-2011 was compiled and interpolated using an inverse distance weighted (IDW) algorithm in ArcGIS. The IDW surface of mussel density was classified by quartiles and the highest quartile was delineated as the core areas of the bed and the lowest quartile was delineated as the peripheral areas of the bed. This resulted in four polygons—two with relatively high mussel densities (core, labelled A1-A5 and B1-B5) and two with relatively low mussel densities (periphery, labelled C1-C5 and D1-D5). Five study plots (5 m x 5 m) were randomly selected within each polygon. Plot C5 was inaccessible, so we used plot C5a. Plots were aligned with the direction of river flow and demarcated into four quarters by driving nine pieces of PVC pipe into the substrate in a 3 x 3 array. To obtain mussels to PIT tag, we haphazardly searched West Newton Chute in August 2012 and obtained 578 mussels, including both common (Amblema plicata, Obliquaria reflexa) and less common (Cyclonaias pustulosa, Pleurobema sintoxia) species. Shells were scrubbed to remove existing zebra mussels. A 20- or 23-mm PIT tag was attached near the umbo of each mussel with cyanoacrylate glue to enable recovery of individual mussels in subsequent years. One end of a 36-cm piece of buoyant fishing line (color coded by species) was glued near the posterior edge of each shell to facilitate recovery. We randomly allocated 9-10 A. plicata and O. reflexa and 4-5 C. pustulosa and P. sintoxia into each plot. Mussels were placed into a randomly chosen quarter of each plot. The age, shell length, and PIT tag identification number of each mussel was recorded prior to placement within a plot. We returned to WNC to recover tagged mussels in August 2013, August 2014, July 2015, and July 2016. Once each plot was found, a diver placed a 2.5 m x 2.5 m PVC frame over each plot quarter to facilitate a thorough search. The diver systematically searched each plot quarter using an 18-cm loop antenna that was connected, via a 15.2 m cord, to a PIT-tag reader located in an attending boat. Surface to diver communication was used to notify the diver when a marked mussel had been found. During recovery efforts, divers searched within each plot and then searched the periphery of each plot (~1-2 m outside each plot) for any marked mussels that might have moved out of the plot. All recovered mussels were identified by PIT tag, recorded as alive or dead, measured for age and shell length, and any attached zebra mussels were removed and counted. If the PIT tag was damaged or missing, we replaced it with a new one and recorded the new PIT tag ID number.

The Minnesota Department of Natural Resources (MNDNR) has been quantitatively sampling a mussel bed in West Newton Chute (a side channel in Navigation Pool 5 of the Upper Mississippi River, UMR) annually since 2008. Briefly, ~200 systematically-placed 0.25 m2 quads are sampled annually; divers excavate substrates to a depth of ~15 cm and place material into a 6 mm mesh bag. Mussels are identified to species, aged via external annuli, measured for shell length, and sexed. From 2008-2016, this mussel bed contained 12-16 live species, had densities that ranged from 4-10/m2, and juveniles (≤ 5 years old) comprised 3-18% of the assemblage. Because this assemblage was well characterized, it represented an excellent location to estimate vital rates (i.e., survival and growth) in mussels. Our objectives were to estimate patterns in survival and growth across four species of mussels and over time within a mussel bed, and to assess if these patterns changed across patches with varying mussel densities. The counts of live mussels in quadrats sampled by the MNDNR during surveys from 2008-2011 was compiled and interpolated using an inverse distance weighted (IDW) algorithm in ArcGIS. The IDW surface of mussel density was classified by quartiles and the highest quartile was delineated as the core areas of the bed and the lowest quartile was delineated as the peripheral areas of the bed. This resulted in four polygons—two with relatively high mussel densities (core, labelled A1-A5 and B1-B5) and two with relatively low mussel densities (periphery, labelled C1-C5 and D1-D5). Five study plots (5 m x 5 m) were randomly selected within each polygon. Plot C5 was inaccessible, so we used plot C5a. Plots were aligned with the direction of river flow and demarcated into four quarters by driving nine pieces of PVC pipe into the substrate in a 3 x 3 array. To obtain mussels to PIT tag, we haphazardly searched West Newton Chute in August 2012 and obtained 578 mussels, including both common (Amblema plicata, Obliquaria reflexa) and less common (Cyclonaias pustulosa, Pleurobema sintoxia) species. Shells were scrubbed to remove existing zebra mussels. A 20- or 23-mm PIT tag was attached near the umbo of each mussel with cyanoacrylate glue to enable recovery of individual mussels in subsequent years. One end of a 36-cm piece of buoyant fishing line (color coded by species) was glued near the posterior edge of each shell to facilitate recovery. We randomly allocated 9-10 A. plicata and O. reflexa and 4-5 C. pustulosa and P. sintoxia into each plot. Mussels were placed into a randomly chosen quarter of each plot. The age, shell length, and PIT tag identification number of each mussel was recorded prior to placement within a plot. We returned to WNC to recover tagged mussels in August 2013, August 2014, July 2015, and July 2016. Once each plot was found, a diver placed a 2.5 m x 2.5 m PVC frame over each plot quarter to facilitate a thorough search. The diver systematically searched each plot quarter using an 18-cm loop antenna that was connected, via a 15.2 m cord, to a PIT-tag reader located in an attending boat. Surface to diver communication was used to notify the diver when a marked mussel had been found. During recovery efforts, divers searched within each plot and then searched the periphery of each plot (~1-2 m outside each plot) for any marked mussels that might have moved out of the plot. All recovered mussels were identified by PIT tag, recorded as alive or dead, measured for age and shell length, and any attached zebra mussels were removed and counted. If the PIT tag was damaged or missing, we replaced it with a new one and recorded the new PIT tag ID number.

The monitoring programs used to determine if sediments and mussels can be used interchangeably to assess environmental condition were: Mussel Watch (MW, National Status and Trends (NS&T), NOAA), Gulfwatch (GW, Gulf of Maine Council), National Coastal Assessment (NCA, US EPA), National Coastal Condition Assessment (NCCA, US EPA), and newly available sediment data from the EcoSystem Indicator Partnership (ESIP). Mussel Watch, Gulfwatch, NCA and NCCA are high profile, long-term, well organized national and regional mussel and/ or sediment monitoring programs. Sediment contaminant data generated by Eastern Charlotte Waterways (ECW) Inc, from funding by the Gulf of Maine Council on the Marine Environment’s EcoSystem Indicator Partnership, were used for sites in the Canadian portion of the GOM; sediments were collected by ECW and analyzed by RPC (http://www.rpc.ca/english/index.html). All the data source programs have quality assurance measures (details can be found at the URLs listed below). NOAA’s NS&T Mussel Watch (NOAA MW) https://en.wikipedia.org/wiki/Mussel_Watch_Program https://products.coastalscience.noaa.gov/nsandt_data/data.aspx Gulf of Maine Council’s Gulfwatch (GOMC GW) http://www.gulfofmaine.org/2/gulfwatch-homepage/ https://gulfofmaine.org/public/gulfwatch-contaminants-monitoring/data-reports/ The Canadian portion of Gulfwatch also has published QA documentation (Sowles et al., 1997). EPA’s National Coastal Assessment (EPA NCA) & National Coastal Condition Assessment (NCCA) https://archive.epa.gov/emap/archive-emap/web/html/about.html https://www.epa.gov/national-aquatic-resource-surveys/ncca https://www.epa.gov/national-aquatic-resource-surveys/data-national-aquatic-resource- surveys EcoSystem Indictor Partnership (ESiP) http://www.gulfofmaine.org/2/esip-homepage/ Eastern Charlotte Waterways Inc. (D. Killorn, pers comm). Sediments were collected by ECW and analyzed through a subcontract to RPC. Data with accompanying QA data were obtained from Donald Killorn, ECW (pers comm). This dataset is associated with the following publication: Elskus, A., L. LeBlanc, J. Latimer, D. Page, G. Harding, and P. Wells. Monitoring chemical contaminants in the Gulf of Maine, using sediments and mussels (Mytilus edulis): An evaluation. MARINE POLLUTION BULLETIN. Elsevier Science Ltd, New York, NY, USA, 153: 110956, (2020).