Anadromous Fish Counts - Milltown Dam
3-Year Project (2018, 2019, 2020)
This project will enumerate all anadromous fish entering the St. Croix River at the lowermost (Milltown) dam. The project forms the basis for measuring progress of current international efforts to restore sea-run alewife, blueback herring and American shad to the watershed, as well as plays an important role in supporting and validating recent alewife population dynamics models being developed to support alewife restoration planning.
The Milltown research trap is operated for an 8-12 week period each year to record the run of alewives (or gaspereau) and closely-related blueback herring, collectively called river herring. Other fish entering the trap are also documented. The research trap and fishway will be opened and activated by NB Power in April each year and the trap will be monitored by daily. The trap was emptied each morning and fish will be hand counted until the run exceeded 1000 fish recorded per hour; at such point, the fish trap will be left open and the fish will be counted on ten-minute intervals each half hour during times of heavy run and the trap will be closed each evening. Weekly trap reports were issued Thursdays following the final trap check each Wednesday evening. The project will provide these counts and other biological data to agencies, legislators, and involved parties to support evolving restoration plans.