2023 Annual River Herring Migration

Each spring, a population of herring loyal to the Mystic River return from Boston Harbor up the Mystic to breed. River herring live most of their lives in the ocean and return to freshwater rivers and lakes to lay eggs. River herring are silver in color and grow to be approximately 10 inches long. Since 2012, the number of herring migrating up the Mystic River, in Boston, has grown from 198,000 to over 800,000. This remarkable restoration success story is the result of improved fish passage at the Mystic Lakes Dam and other locations resulting in 200+ acres in expanded habitat for herring to spawn. The great news is that there are additional improvements coming soon. This aerial footage provides great views of the final step in this amazing annual spring migration process!