Eight fishways on six New Hampshire (NH) coastal rivers were operated during the spring of 2016 to facilitate the passage of river herring (Alewife Alosa pseudoharengus and Blueback Herring Alosa aestivalis), American Shad Alosa sapidissima, and other diadromous fish over dams.
Estimated numbers of river herring using all coastal river fish ladders in 2016 increased by approximately 40.5% from 2015. Alewives dominated returns to the Cocheco, Exeter, and Lamprey rivers while the Oyster River had a slightly higher percentage of Blueback Herring returning. The Oyster River continues to have low return numbers and exhibits signs that habitat problems are inhibiting restoration efforts. The Winnicut River fishway is ineffective at passing river herring and an investigation to determine a solution is ongoing. In the absence of restoration efforts, no American Shad returned to NH fishways in 2016.
In an effort to enhance local spawning stocks, thousands of river F-61-RI-1_16_AR Page 2 herring were transferred from the Cocheco and Lamprey rivers to the Merrimack River drainage to assist in anadromous fish restoration efforts. In 2016, 2,250 river herring were stocked in impoundments or lakes within the Great Bay Estuary drainage. The NH Fish and Game Department has continued to work with state and federal agencies and non-governmental organizations on various cooperative diadromous fish passage projects on coastal NH rivers.
NH Fish & Game, "Diadromous Fish Investigations, 2016: Anadromous Alosid Restoration and Evaluation" (2017). PREP Reports & Publications. 396.