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In recent years, river herring populations have plummeted throughout the Northeast and Mid-Atlantic regions. River herring include two closely related species, alewife (Alosa pseudoharengus) and blueback herring  (A. aestivalis). They are anadromous fish, meaning that they spawn and grow up in fresh water ponds, lakes and streams but live most of their adult life in the sea. River herring have historically been an important food source for both humans and wildlife. On Cape Cod, herring run management in some towns dates back to the late 1700’s. During their spring spawning migrations, river herring are a key food item for birds, wildlife and other fish.
Because of this population decline the Massachusetts Division of Marine Fisheries (DMF) enacted a ban on the catch, sale or possession of river herring in 2005. Other states enacted similar bans. The population decline is thought to be due to several causes:
- Overfishing
- Habitat loss due to water withdrawals and barriers to migration
- Water pollution
- Poaching
- Natural predators
The ban is still in effect as river herring populations have not sufficiently recovered.
Fisheries scientists need more information to better understand herring ecology, and fishery managers need accurate information on river herring populations to better protect and manage their fisheries. One way of obtaining estimates of herring migrations is to conduct counts to estimate the size of the annual spring migration (run).
Since 2007, APCC has helped communities to conduct volunteer herring counts to estimate the size of the annual herring run along streams. APCC works with partners and volunteers to conduct fish count programs in the following towns:
 Stony Brook in Brewster provides fish passage to 386 acres of spawning habitat in five ponds. Information from this count program was essential for obtaining federal funding for the Stony Brook Salt Marsh and Fish Passage Restoration, which replaced an undersized culvert under Route 6A with an 18-foot culvert. 2007 – ongoing
- Pilgrim Lake run (aka Herring Brook) in Orleans provides fish passage to 39 acres of spawning habitat in Pilgrim Lake. Volunteer counts of herring and American eels enabled the Town to obtain state and federal support to restore the lower part of the herring run and install a new eel ramp. 2008 – ongoing.
- Herring River in Wellfleet provides fish passage to 157 acres of spawning habitat in four ponds. This count program is supporting the planned Herring River Salt Marsh Restoration Project, which will restore 1,100 acres of salt marsh by increasing tidal flow. 2009 – ongoing.
- Herring River in Harwich provides fish passage to 1119 acres of spawning habitat in four ponds. 2009 – ongoing.
- Coonamessett River in Falmouth provides fish passage to over 188 acres of spawning habitat in three ponds. This count program was started in 2004 and in 2009 the Coonamessett River team joined the APCC program.
- Mill Creek in Sandwich is the town’s only active herring run and the newest edition to APCC’s Herring Count Program. In 2008, APCC helped the town to obtain grants to replace the fish ladder at Upper Shawme Pond dam, which was rebuilt in 2009. The new fish ladder will allow herring to once again reach Upper Shawme Pond which, combined with Lower Shawme Pond provides over 24 acres of spawning habitat. APCC is working with the Sandwich Department of Natural Resources on this new program.
 Results:
Herring count data are sent to state and federal fisheries managers who monitor the status of river herring populations. Run sizes in the Cape Cod streams where counts have been performed vary from low (about a thousand) in the Pilgrim Lake run to high (several tens of thousands) at Stony Brook, Herring River in Wellfleet, Herring River in Harwich, and the Coonamessett River. This chart compares the run size for different streams and different years, and also provides upper and lower 95% confidence intervals (“error bars”).
In addition to estimating run size, count data also tell us when the fish begin and end their migrations, the water temperature at these times and other important information that helps us to understand when and how herring migrate.
Herring count data are also important for making the case for restoring fish runs in need of repair or improvements. For example, fish count data from Stony Brook and Pilgrim Lake were instrumental in obtaining grant funding for restoration projects. The count program in Sandwich will help to demonstrate the benefits of the town’s restoration work in the upper Mill Creek watershed.
Finally, herring count data are used together with datalogger monitoring of water temperature and water level to look for signs that climate change may be impacting our fish runs. Water temperature is important for herring; the adults start their spring spawning migration when water temperature in the run is about 50º Fahrenheit. As water temperatures rise due to global warming, our concern is that herring runs will be affected. Also, high water temperatures in ponds can threaten the young fry maturing there.
Fish count programs help to build support for stewardship and restoration of water resources and habitat. For example, in Brewster and Orleans, the counts collected by volunteers were instrumental in demonstrating that these were important fish runs deserving of restoration and protection. Based in part on this data, agencies such as NOAA (National Oceanic and Atmospheric Administration) and the Gulf of Maine Council for the Environment provided grants for restoration, and other agencies such as DMF, local herring wardens and natural resource departments provided technical support.
 Herring count programs can also help determine the preservation needs of other aquatic species. In several towns, volunteers counted or observed American eels, a catadromous fish species that is also in decline. Catadromous fish are born in the sea but migrate to fresh water ponds and lakes to grow, before returning to the sea to spawn. Since state and federal fisheries managers are also interested in restoring habitat for American eels, our counts benefit both anadromous and catadromous fish.
Partners:
Our herring monitoring partners are numerous and include municipal staff, town committees, non-profit organizations, individuals who support this program, the Barnstable County Coastal Resources Committee, the Massachusetts Bays Program and state and federal agencies working to protect and restore the environment.
For more information or if you are interested in volunteering to count herring, contact Dr. Jo Ann Muramoto at 508-362-4226, or simply fill out our Volunteer Contact Form.
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