Most of this information was provided by the Parker River Basin Team
The Parker river and its headponds provide the habitat necessary to maintain a self sustaining population of alewives (Alosa pseudoharengus). Each spring, adult alewives return from the ocean to their natal pond for the purpose of spawning. This annual event has taken place for centuries in the Parker River system.
Belding (1921) documents the establishment of a public in-river alewife fishery in 1793 with an annual production of approximately 100 barrels. Beldings' report chronicles other important landmarks in the histor of both the management and abuse of the Parker River alewife resource, notable dates include: first fishing restrictions established in 1793 limiting the fishing period, net size, number and mesh; (1805) provisions were made for fish passage at dams/ and in 1808 the Town of Newbury appointed a herring committee that immediately enacted regulations concerning the location of where herring could be harvested as well as the prohibition of ice fishing. The fact that a herring committee was established and regulations were adopted indicates that the annual herring run was important to the local residents.
The late 18th and early 19th centuries were a period of growth and industrialization in New England and the impact on all anadromous fish species was devastating. Construction of dams to provide water power for various mill types (grist mills, saw mills, and textile mills) prevented the fish from returning to their spawning areas. Throughout the northeast, once abundant runs of Atlantic salmon, American shad, alewife, blueback herring and Atlantic sturgeon were reduced to such low levels that most were totally extirpated or reduced to barely self-sustaining levels. The Parker River was no exception to this trend and was also severely impacted by the construction of dams that prevented the alewife from reaching their historic spawning areas in Pentucket, Rock and Crane Ponds. Belding indicated taht five dams were in place in the Parker River prior to 1921 and three of these dams (Byfield Woollen Mill, Byfield Snuff Co. #5 and Pearson Tobacco Company) had no provisions for fish passage. The following quote from Beldings' 1921 report offers a glimps of the status of the alewife run: "Ins spite of numerous good early laws, the fishery in the Parker River is ruined, primarily through obstruction by dams without fishways, ... a condition due to laxity in law enforcement on the part of the town of Newbury. Considering its current unproductive status and several impassable dams on the river, reclamation of this fishery though possible, does not present the attractive opportunities offered by many other streams."
Despite the bleak picture painted by Dr. Belding concerning the reclamation of the Parker River alewife population, five fishways were constructed during the 1930's with the aid of WPA funds. A fishway at the outlet of Pentucket Pond was installed in the early 1960's facilitating access to the primary spawning habitat. Collectively, these six fishways provided alewives a passable route around the dams and access to their historic spawning grounds.
Alewife populations in the late 60s through the 1970s were quite healthy. Adults returning to the river in mid-April readily utilized the fishways to successfully reach sutable spawning areas. Minor repairs were done in 1974 to the fishway at the Central St. dam by the Division of Marine fisheries fishway construction crew. Since that time, the condition of all six fishways have deteriorated to the point where some are barely passable and the fishway at the outlet of Pentucke Pond has totally washed out. It is only due to the efforts of sportsmen from the Essex County Sportsmen's Club, who have adopted the Parker River through the "Fishway Stewardship Program," that any alewives now reach the spawning grounds. These volunteers spend a considerable amount of time each spring cleaning debris, regulating flows and making temporary repairs where possible.
Today, the Parker River alewife run is again a mere shadow of its potential and is in serious risk of total collapse. The primary reason for the decline is the same as it was many years ago, inadequate fishways. Many of the fishways constructed in the 1930s have received very little attention and are crumbling due to age and neglect. If the alewife population is to rebound in the Parker River, a commitment must be made to the reconstruction of adequate fish passage facilities and insuring that adequate flows exist during the spring spawning run and during the juvenile outmigration in the late summer and early fall.
In the spring of 1997, the Parker River Clean Water Association coordinated a volunteer counting effort to estimate the number of spawning alewives in the Parker River. Only about 6,000 fish returned to the river in 1997, less than 1/5 of the number that were observed in the 1970s. An additional problem is that low flows during the summer of 1997 have hampered the outmigration of juveniles.