A three-year Anadromous Fish Action Plan will enhance anadromous fish resources in the embayments and associated watersheds adjacent to the Hubline construction activities. These are resources that were potentially impacted by the Hubline construction. The restoration project will consist of propagation/stocking, monitoring, construction and repair of anadromous fish passage, and improvements to habitat. The project will consist of three parts as described below.
Part 1: Anadromous Fish Passage Enhancements
The first part of the project will enhance and increase spawning habitat for alosid fishes (alewives, Alosa pseudoharengus; blueback herring, Alosa aestivalis; American shad, Alosa sapidissimus). A prioritized list of construction/repair projects for new and existing fish passage structures is being generated from sites where anadromous fish are impeded or blocked from reaching their spawning grounds. Many of these projects are located in watersheds associated with the Hubline construction area. Based on this prioritized list, MarineFisheries will select several key construction/repair projects in the vicinity of the Hubline project that can be completed over the next few years and that will restore or enhance hundreds of acres of anadromous fish spawning habitat.
In all cases where runs have been severely depleted or extirpated because of problems of passage, MarineFisheries will transfer spawning adult fish of the appropriate species from a healthy donor run to the depleted run after the fishway repair/construction is completed. This is done at the time of the spring run using a MarineFisheries stocking truck. About 3 -7 thousand adults are stocked in this manner each year, with the number dependent on the size of the restored habitat. Larvae produced from these transferred fish will imprint on the new system and will return in 3-4 years to re-stock the run. Transfers into depleted runs will be made for at least 3 consecutive years in order to ensure the establishment of a run. Runs will be monitored each year for the presence of returning adults.
Part 2: Rainbow Smelt Propagation and Habitat Enhancement
Project contact: Brad Chase
MarineFisheries will assist the restoration of rainbow smelt (Osmerus mordax) populations in several locations including the Crane and North Rivers in the Beverly-Salem area, the Neponset River in Milton/Dorchester, and the Fore Rive in Weymouth. Efforts will include the physical enhancement and restoration of spawning habitat by carefully planned manipulations (addition of spawning substrate, providing better river contours) and by the implementation a larval hatching/stocking program. The method uses stream-side portable hatcheries to greatly enhance larval production. Recent data indicate that mortalities in the egg stage caused by algal overgrowth may be a significant factor in the decline of smelt. This propagation technique reduces egg mortality from 80-100% to less than 10%.
Part 3: American Shad Propagation
American shad (Alosa sapidissima) is the largest member of the Clupeidae (Herring) family, capable of reaching a weight of 7-8 pounds and a length of up to 30 inches. Each spring, adult shad migrate from the ocean into coastal rivers from Florida to Newfoundland. American shad were formerly an important component of the anadromous fish fauna in Massachusetts. Shad were historically abundant in the larger rivers of the Commonwealth including the Connecticut, Merrimack, Neponset, and Charles Rivers, and also in a few smaller rivers including the Palmer and Indianhead. They were extirpated or reduced to extremely small, unsustainable populations in all the rivers where they occurred by the construction of dams, water pollution at the spawning grounds, and over-fishing over the last century. In times of abundance, shad supported both commercial and recreational fisheries. At present, commercial fishing for shad is prohibited in Massachusetts, and a small recreational fishery takes place in the Merrimack and Connecticut Rivers. The populations in these two rivers have rebounded in recent years because of good recruitment likely resulting from significant improvements to water quality and the construction of efficient fish passage structures on dams. The populations in the other rivers remain very low or non-existent.
The intent of this project is to restore viable populations of American shad to the Neponset and Charles River. This will be accomplished through a fry stocking program in conjunction with fish passage improvement projects outlined above. Brood stock will be obtained from the Merrimack River at the Essex Dam fish lift in Lawrence, MA. Shad will be spawned at the USFWS hatchery in Nashua, NH. The larvae will be raised for about 8-12 days before release into the upper Neponset and Charles Rivers as fry. All fry will be immersed in a tetracycline bath in order to mark their otoliths prior to release. Marking in this way will enable us to quantify hatchery returns in 3-4 years.