The Fish in Your River

Help protect the fish in the Ipswich River by participating in the annual fish count! Attend the training on March 19: 7pm at 143 County Rd, Ipswich.

Imagine the Ipswich River prior to development and the construction of dams; the river and its tributaries were free flowing, with abundant riffles and pools. The river supported diadromous (migrating between fresh and salt water) fish runs numbering in the millions. The river supported such fish as Alewife and Blueback herring, Rainbow smelt, Atlantic salmon, Striped bass, American shad, Sea Lamprey, sturgeon and American eel.  In fact, the river’s original name, Agawam is a Native American term meaning “place where fishes of passage resorted” which is indicative of the prior abundance of migratory fish. The harvest of alewife (river herring) as far upstream as Wilmington was an important part of the local economy, and Wenham Lake, now a public water supply reservoir, was the most important alewife nursery in the region. The water temperatures were also consistently cold and high in dissolved oxygen, supporting species that require flowing waters or “river fish” such as Eastern brook trout, White sucker, Fallfish, Creek chubsucker, Johnny darters, White perch, Rainbow smelt, shad and Atlantic salmon that depend on flowing water.

Today, the Ipswich River is heavily impacted by low flows (from water withdrawals for public drinking supply) and dams, which impact the native fishery. Fish species that require flow are at a disadvantage, and the river is dominated by generalist species that can tolerate warm water and ponded conditions, mainly redfin pickerel, American eel and pumpkinseed. These “pond fish” currently make up over 80% of the fish biomass in the river.

Today, the Ipswich Mills Dam is a relic of our early industrial past. The current fishway, rebuilt in 1996, allows some river herring, sea lamprey and sea run trout to ascend into the pool behind the dam but like all fishways is only partially effective. Other migratory species such as rainbow smelt and American shad will not use the fishway at all. A team of economists and fish ecologists recently found that in spite of state-of-the-art fish passage facilities on major Northeast U.S. waterways, including the Merrimack and Connecticut rivers, actual numbers of fish passing through them over several decades reached only a tiny fraction of targeted goals.

In an attempt to measure success at the Ipswich Mills Dam fishway, the Ipswich River Watershed Association’s annual Fish Count monitors herring using the fishway to enter the river above the dam. From April 1 to mid-June volunteers perform 10 minute counts throughout the day at the top of the fishway looking for fish like herring, shad or lamprey. The data are used to document the conditions under which these fish migrate into the Ipswich River to spawn.

Since monitoring began in 1999, the most river herring observed in the Ipswich River was 133 fish in 2008 This is a tiny fraction of the historic herring run for this river but we are not alone; according to the Herring Alliance some river herring runs on the Atlantic Coast have declined by 95% 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, access to spawning habitat, and natural predators. We hope that through participation, volunteers will increase their understanding and stewardship of the Ipswich River and the fish species it supports.

To find out how to help protect river herring by participating in the annual fish count, contact the Ipswich River Watershed Association at (978) 412-8200 visit our website or find us on facebook,


  1. Christina - March 29, 2014

    My fishing partner and I frequent the North Reading section of the river where the park is. We mostly catch black crappie (calico bass), pumpkinseeds, and there has been the occasional chain pickerel, a baby largemouth bass one time, and a decent sized brook trout one day. What really surprised me is the day I caught a little brown bullhead catfish right off the beach. We always catch & release. I wonder if a catfish that far up the river or any of these other finds is an indication of improvement as well.

    We could go anywhere but we just love the Ipswich. So beautiful and peaceful!

  2. Cynthia - January 31, 2014

    Thanks. I wish I could say I do have any tips but I am not sure how we got listed there. Glad you like the blog. Keep your eye on our website this spring for more fish news!

  3. Cynthia - April 26, 2013

    Absolutely, that is very exciting. They are definitely an indicator of a healthy river. Thank you so much for letting us know about your sightings. Hope to hear more good news from your fishing adventures in the future!

  4. Brian - April 25, 2013

    Hi, I was fishing the Ipswich in Middleton today and I caught a Chub I’ve never seen before. With a little research on the internet I’m fairly certain it was a Fallfish. I saw more than a few fish sipping the surface as well as have two fish hit my lure that I didn’t catch. In your article you mention that Fallfish require good quality, flowing water. My question is does the presence of Fallfish at least an encouraging sign that water quality may be improving? Or am I just being too hopeful?

  5. Cynthia - March 26, 2013

    Thanks Margaret! The more counters we have, the more fish we may see. Please contact Ryan O’Donnell at to find out more about the fish count.

  6. Margaret Whittaker - March 26, 2013

    My husband and I would like to participate on one of the weekends to help count the herring.