First published in Landings, April, 2013.
This spring the Maine Legislature is set to hear from the public on bills to restore river herring (alewives and blueback herring) to the St. Croix River. The St. Croix could be the biggest source of these fish, offering many acres of freshwater lake habitat for spawners before they return to the ocean where the fish spend most of their lives. I expect that Legislators will hear from lobstermen, Passamaquoddy Tribal members, scientists and alewife harvesters, all in favor of reopening this once- important river. At the same time that our legislators are getting up to speed on where, when and how river herring live and reproduce, efforts are underway to consider listing alewives and blueback herring as endangered species throughout their ranges on the East Coast. Why all this interest? And why should you care about the fate of these fish?
Alewives and blueback herring are hard to tell apart; they are usually managed and harvested together and known as “river herring.” It’s no secret to lobstermen that river herring make good bait. Sales of alewives fill the coffers of those Maine towns that have the rights to harvest and sell alewives. Nineteen Maine municipalities are now allowed to harvest alewives four days per week. The fish can move freely up river the other three days. Maine’s Department of Marine Resources works with these towns to ensure that the number of returning adults alewives is maintained. In 2012 over 1.6 million pounds of alewives were sold bringing more than $425,000 into Maine’s economy, substantially more than the 1.1 million pounds were harvested in 2011.
Last year marked the highest statewide alewife harvests recorded since 1979, a positive sounding trend. Overall since the 1970s, however, we have seen a greater than 93% decrease in commercial landings of river herring nationally. It’s a dire situation. Extinction risk models are being analyzed by NMFS for alewives and blueback herring right now. The results of these analyses will determine if one or both species receive an Endangered Species designation. Currently alewives and blueback herring are a NOAA National Marine Fisheries Service “species of concern.”
When it comes to local food, river herring are the original “Made in Maine” product. For thousands of years they have been caught by humans and devoured by all sizes and shapes of other creatures in lakes, rivers and the ocean.
The life cycle of river herring is similar to the Atlantic salmon—adults return to rivers to lay eggs in fresh water, then return to live most of their lives in marine waters. The spring migration of river herring into our waters creates a pulse of energy after long and hungry winters. Alewives and blueback herring are not glamorous species; their volume is their value. Where other creatures have developed tricks like camouflage, speed or concealment to elude predators, these fish have simply relied on numbers, coming up Maine’s rivers to spawn in the spring in such great numbers they could be eaten by a whole host of creatures like bald eagles, osprey, great blue herons, cormorants, mink and bear, yet still leave healthy numbers to reproduce and return to the ocean.
River herring eggs feed lake-dwelling creatures. After a few months of freshwater growth the young-of-year fish move back down rivers to the ocean, providing an energy-rich snack for other predators they encounter, and serving as a “prey buffer” to hide salmon smolts moving in the same waterways.
Certainly their status in Maine has risen over the past decade as scientists have come to understand their ecological value. Scientists now theorize that damming of coastal rivers contributed to the collapse of the cod fishery in the Gulf of Maine by reducing the numbers of alewives, one of the cod’s principal prey items. Scientists believe that the restoration of groundfish stocks in the Gulf of Maine will benefit from restoration of river herring populations.
History hasn’t been friendly to river herring. Our habit of damming and polluting rivers has reduced access to important spawning grounds. As their numbers have dropped, so has our memory of their presence. Nowhere is that more dramatic than in the St. Croix watershed. That river has the potential to bring 25 million adults back to spawn annually, more than any of our other rivers. Voices from the past tell us that river herring were important there generations ago; historic petitions to the Maine Legislature from the 1820s attest to this. The language is old but the idea is the same today: river herring are important. A reopened and healthy St. Croix River will offer many benefits.