Diadromous fish migrate between fresh and marine waters to complete their life history. They are valued for the forage they provide to a wide range of fish and wildlife and were formerly important for traditional small-scale fisheries in coastal towns. Diadromous fisheries management is split statewide for river herring and striped bass and up to the first dam for other species at which point the Department of Fisheries and Wildlife takes over. DMF is responsible for the management of diadromous fish populations, and the restoration, improvement, and maintenance of migratory pathways in coastal rivers.
Diadromous Fish Passage and Habitat Restoration
A central role for DMF is helping sea-run fish migrate from the ocean to freshwater habitats. This work involves collaborative, large-scale fish passage and small-scale fish ladder, habitat improvements, and eel ramp construction projects. Included in these efforts are regulatory features to assist the management of diadromous fish passage through the issuance of DMF Fishway Construction Permits, fishway operation and maintenance plans, and diadromous fish stream maintenance plans.
River Herring Monitoring
One of our project’s largest efforts is the annual monitoring of spring spawning runs of alewife and blueback herring, historically the most abundant and valuable diadromous fish in Massachusetts, and known together as river herring. We manage eight monitoring stations where river herring are counted with either electronic or video counters and biological samples are collection to track annual population metrics. These data contribute to the ASMFC river herring population assessment. We provide assistance to numerous local groups with river herring counting efforts, and participate in several collaborative research projects on river herring life history.
American Eel Monitoring
DMF participates with standardize monitoring of glass eels (also called young-of-the-year - YOY) under ASMFC coordination. This monitoring of YOY eel migrations contributes to a coast-wide index of eel population relative abundance.
We also design and install eel ramps in Massachusetts coastal rivers to assist their upstream migrations. Nine have been installed since 2007. Ramps have a collection tank that tracks performance of the eel ramp and can be used for census counts of YOY eels. Local groups help at most sites with collecting and transporting juvenile eels upstream. To date, the ramps have given a boost to over a half million eels at these passage barriers.
Rainbow Smelt Monitoring
Rainbow smelt are a popular sport fish in Massachusetts and important forage fish for many species. Recent smelt population declines have prompted DMF to increase monitoring of spawning habitats in coastal rivers. We also conduct ongoing in-stream fyke net monitoring of smelt spawning runs.
The fyke net monitoring has documented biological characteristics of smelt spawning runs. Monitoring has also documented the presence of over 35 species of fish in coastal rivers including 10 diadromous species and contributed to a Gulf of Maine Conservation Plan for rainbow smelt.
River Herring and Shad Stocking
DMF uses a stocking truck to re-establish, augment, and enhance native diadromous fish runs. We work collaboratively on large stocking efforts, however most work involves small-scale trapping and moving pre-spawning river herring within coastal drainage areas. DMF works with the U.S. Fish and Wildlife Service on the restoration of American shad in the Charles River. We also are investigating other river systems that are suitable for shad restoration.
DMF gives technical help to towns and cities, organizations, and other agencies with diadromous fish resources. Help can amount to a few hours for individual inquiries or dedicated efforts to specific tasks. Technical help includes:
- River herring habitat assessment
- River herring sustainable fisheries plan
- Diadromous fish restoration priority list
- River herring network