The Cohasset Center for Student Coastal Research is an organization dedicated to educating students in coastal research by providing them with opportunities for hands on experience with guidance from the subject matter experts. The purpose of this study was to identify anadromous fish (alewives, Alosa pseudoharengus; and blueback herring, Alosa aestivalis) in the Gulf River estuary. Results from the project will inform the state’s larger effort to restore river herring populations to sustainable levels in the Gulf River. The results from this survey will provide information on the proper implementation of management initiatives in the watershed including the Hunters Pond dam and fish weir restoration projects.
No anadromous fish were counted at the herring run fish ladder located at Hunters Pond at the freshwater upper reaches of the Gulf River. The site closest to the mouth of the river, Shockman’s dock (site ID name), has the most diverse nekton. Winter flounder (Pseudopleuronectes americanus), sea star (Asterias forbesii), and hermit crab (Pagarus longicarpus) were documented exclusively at the mouth of the estuary. Large populations of Atlantic silversides (Menidia menidia) and shrimp (unidentified) were encountered at all sites. Mud Snails (Illyanassa obsoleta), Green crab (Carcinus maenas), and Mummichogs (Fundulus heteroclitus) were found at the mouth and the other saline site, Musquashcut Brook (site ID name), but generally not found at Hunters Pond (site ID name), the more freshwater location. The four- and nine-spine stickleback fish (Apeltes quadracus) were predominantly found at Hunters Pond. The saline sites show low numbers of enterococci bacteria except following high rainfall events. However, bacteria counts at Hunters Pond downstream of the herring run are consistently above safe levels, exceeding the state limit of 104 cfu/100ml. Physical and chemical water quality data were within expected ranges for this historically studied estuarine system. Conductivity, salinity and pH data are consistent with saline versus freshwater regions of the estuary. The more freshwater site has the lowest chlorophyll-a levels. Water quality impairment preventing a healthy herring run was not found. Details of the project methodology and findings are provided in the final report file size 1MB.