It’s been called the “poor man’s tarpon”: the American shad, a hard fighting and agile leaper when hooked, is a species that has been targeted by anglers in the Commonwealth of Massachusetts and throughout its range for centuries. Shad could be found in many river systems across the Commonwealth during spring months as they moved upstream from the ocean to spawn in slower-moving freshwater habitat. Many factors contributed to the decline of the American shad in Massachusetts. Decreases in water quality, dam construction and exploitation due to overfishing all but wiped out populations of shad in many systems such as the Charles River. Now, water quality has improved due to the Clean Water Act and access to spawning and nursery areas has been made possible by fishway construction. These improvements have allowed for the potential to bring back American shad to their once native systems.
Since the spring of 2006, the Division of Marine Fisheries along with the U.S. Fish and Wildlife Service and the Charles River Watershed Association have been working to stock marked shad larvae back into the Charles River in hopes of repopulating the system. Adult shad are captured from the Merrimack River in Lawrence and transported back to the hatchery where they are allowed to spawn naturally in tanks. The fertilized embryos are incubated and hatched. The hatched larvae are marked with a fluorescent chemical on the bony structures in the head of the fish called otoliths, which are analogous to human ear-bones and aid fish in balance and equilibrium. The marked otoliths can be dissected later from a returning adult shad and viewed under a microscope. The marked shad larvae are then stocked in batches numbering over 200,000, with a goal of three million each year being placed into the Charles River in Waltham. To date, over 10 million larvae have been stocked since the project’s inception.
Monitoring for returning adult shad began in the spring of 2010 when the first adults from the 2006 larval stocking could return. While no adult shad were observed during 2010, in the spring and early summer of 2011 nine adult shad were captured during electroshocking sampling. Of the nine adults captured, four were marked 5-year old shad that had been stocked in the spring of 2006.
The return of marked adult shad in the Charles River system is a major success for the diadromous restoration program. These captured shad spent four years in the ocean, returning to the river from which they had been stocked. Sampling will continue in the Charles River system for the foreseeable future, with the hope that many more shad return each year and begin to spawn naturally.
Regulations in red are new this year.
Purple text indicates an important note.