What is a herring run?
A herring run refers to the annual spring migration of adult river herring that migrate from the Atlantic Ocean to New England rivers like the Charles, to spawn.
Which species are involved?
During the herring run, visitors can find alewife and blueback herring swimming up the Charles.Currently the Charles boasts a thriving blueback herring run, one of the largest in Massachusetts, so blueback herring are likely the most visible fish right now. The blueback and alewife herring look very similar, with the alewives slightly larger in size.
The larger American shad are also migrating to the Charles, although they are rarer, as decades of pollution and the construction of dams have contributed to their decline. Since 2006, CRWA along with the Massachusetts Division of Marine Fisheries (MA DMF) and the U.S. Fish and Wildlife Service (US FWS)have been working to restore the American shad population in the Charles. The program aims to restore a viable population of American shad in the Charles, improve the ecological health of the river by introducing a native species, and create a local sport fishery for anglers.
The herring run takes place every year, typically from mid-May until mid-June.
Where can I see river herring in the Charles?
The best place to view the migrating river herring and is at the Watertown Dam. Here, herring are often seen jumping the dam, navigating the fishway, and gathering downstream and upstream. Visitors to the dam can also find trails with interpretive signage for more information. The Massachusetts Division of Marine Fisheries has installed a camera to help monitor the herring run, and to see what species and how many are migrating.
Check out this video from DMF’s herring cam at Watertown Dam.
Currently, the run is so large that you can also see herring along the banks of the Charles along the paths in the lower basin in Watertown, Cambridge and Boston!
Why is the herring run important?
Over the last century, the river herring population has declined throughout the region due to numerous threats like poor water quality, the capture of adults in other fisheries, and spawning habitat blocked by the construction of dams. The presence of a thriving herring migration in an urban watershed like the Charles shows that our efforts to restore the river and its’ fish population are working!