By Beth MacBlane and Elizabeth Glivinski
Since 1972, the Mystic River Watershed Association (MyRWA), a non-profit organization based in Arlington, Mass., has worked to protect environmental conditions for more than half a million residents within the 22 communities in the Mystic River Watershed. MyRWA improves the conditions of the lakes, ponds and tributaries by taking action on three fronts: water quality monitoring, education and outreach, and policy and advocacy.
The Mystic River ecosystem supports two species of herring: Alewife (Alosa psuedoharenous) and Blueback Herring (Alosa aestivalis). Both species, collectively called river herring, are anadromous. This means they spend most of their lives at sea and return to rivers – like the Mystic – to spawn.
The Mystic River Herring Monitoring Program, initiated in 2012, has proven to be one of the most successful water quality initiatives in recent years. The goal of this program is to collect valuable data about herring populations as they make their way up the Mystic River to reach their native spawning grounds, and to educate the public about river herring. Over 80 trained volunteers monitor herring at the Upper Mystic Lake Dam fish ladder in Medford, Mass., which was installed in 2011 during renovations to the dam. This data is used to estimate the total herring run size and is shared with the Massachusetts
Division of Marine Fisheries to help inform trends across the Commonwealth. Previously, the dam did not include a fish ladder, which prevented river herring from reaching their native spawning grounds, a common problem in many urban river systems.
In 2013, monitors counted 23,635 herring from April 1 through June 26. Using modeling soft ware provided by the Massachusetts Division of Marine Fisheries, the Mystic River herring run was estimated to be 193,125 +/- 24,250 herring. The 2012 results were comparable.
In colonial times and earlier, herring in the Mystic River were extraordinarily abundant. From the 1900s until today, a much smaller population of river herring is present. According to the Herring Alliance, some river herring runs on the Atlantic Coast have declined by 95 percent or more over the past 20 years. In 2006, the National Marine Fisheries Service designated river herring as a species of concern. Population decline may be associated with numerous factors including by-catch, habitat loss and degradation, water pollution, poaching, access to spawning habitat and natural predators.
The public is encouraged to witness the herring (and American eel) migration during an “open house” at the Upper Mystic Lake Dam. These family-friendly events are set for Monday, May 12 from 3-7 p.m., Sunday, May 18 from 11 a.m. to 2 p.m., and Saturday, May 24 from 11 a.m. to 2 p.m. as part of World Fish Migration Day.
We hope to see you on the Mystic!
Photo credit David Mussina.