BANGOR DAILY NEWS • May 13, 2025
Alewives are river herring that live most of their lives in saltwater but travel to freshwater each year to spawn. Historically they were caught in Maine and canned and smoked, but now, they’re mostly used as lobster bait. Although the construction of dams blocking rivers dramatically reduced alewife populations in Maine over the past centuries the fish is making a comeback. Thanks to the restoration of fish ladders and the removal of dams spearheaded by environmental organizations and volunteers, the river herring’s population in the Penobscot River grew to six million by 2023. The Damariscotta Mills Fish Ladder Restoration is one example of a group renovating a fish ladder that was first built in 1807. The annual alewife migration draws visitors from across the state, and even across the country, to witness the fish travel upstream. Birders also flock to alewife migrations to witness the eagles and ospreys feast.