There’s great fishing to be had in the Neponset Watershed!
However, there may be more to your freshwater fish than meets the eye. Make sure to stay up-to-date on all fish advisories and be sure your catch is safe to consume.
For questions or comments about local fish in the Neponset Watershed, please contact NepRWA River Restoration Director, Sean McCanty.
Fish Advisory
Fish can absorb pollution from the water, so before eating any local fish:
- Check the area for advisories or warnings
- Keep up-to-date on the Freshwater Fish Consumption Advisory List, published by the MA Department of Health
- Contact the MA Department of Public Health, Center for Environmental Health, with any questions: 617-624-5757
See Neponset Watershed pollution warnings for fishing:
Because of various levels of risk, the state has different recommendations for what fish are safe to eat for the general public and members of sensitive populations — children younger than 12 years of age, pregnant women, women of childbearing age who may become pregnant, and nursing mothers. Across our Watershed, the pollutant of concern is different: from mercury, to PCBs, and DDT.
Here are the advisories in our Watershed:
Ponkapoag Pond, Canton
Contaminant: Mercury
Sensitive Population Meal Advice: Do not eat any largemouth bass or chain pickerels
General Public Meal Advice: No more than 2 largemouth bass or chain pickerels per month.
Lake Massapoag, Sharon
Contaminant: Mercury
Sensitive Population Meal Advice: Do not eat any largemouth bass
General Public Meal Advice: No more than 2 largemouth bass per month.
Neponset River (Boston, Canton, Dedham, Milton, Norwood, Sharon, Walpole, Westwood)
Between Hollingsworth & Vose Dam in Walpole and Walter Baker Dam in Boston.
Contaminant: PCBs and DDT
Sensitive Population Meal Advice: Do not eat any fish from this area
General Public Meal Advice: Do not eat any American eel or white suckers from this area, and no more than 2 fish of any species per month.
Canton River (between Neponset River and Neponset St. dam), Canton
Contaminant: PCBs and DDT
Sensitive Population Meal Advice: Do not eat any fish from this area
General Public Meal Advice: Do not eat any American eel or white suckers from this area, and no more than 2 fish of any species per month.
Mother Brook (between Charles River and Knight Street Dam), Dedham, Boston
Contaminant: Mercury and DDT
Sensitive Population Meal Advice: Do not eat any carp, largemouth bass, or white suckers from this area
General Public Meal Advice: No more than 2 carp, largemouth bass, or white suckers per month
Mother Brook (between Knight Street Dam and Neponset River), Boston
Contaminant: PCBs and DDT
Sensitive Population Meal Advice: Do not eat any fish from this area
General Public Meal Advice: Do not eat any American eel or white suckers from this area, and no more than 2 fish of any species per month
Pettee Pond, Walpole & Westwood
Contaminant: Mercury
Sensitive Population Meal Advice: Do not eat any largemouth bass
General Public Meal Advice: No more than 2 largemouth bass per month.
Reservoir Pond, Canton
Contaminant: Mercury
Sensitive Population Meal Advice: Do not eat any largemouth bass or white perch
General Public Meal Advice: No more than 2 largemouth bass or white perch per month.
Willett Pond, Walpole, Westwood & Norwood
Contaminant: Mercury
Sensitive Population Meal Advice: Do not eat any largemouth bass
General Public Meal Advice: No more than 2 largemouth bass per month.
Report a Problem. Ask a Question.
You can help to keep our streams and ponds clean by reporting anything suspicious looking near the water or by storm drains.
Email the Neponset Stormwater Hotline at stormwater@neponset.org or give us a call at 781-575-0354 x 300. If we can’t solve the problem or answer the question on the spot, we will relay it to the appropriate agency for further action.
Invasive Fish: Snakeheads
Since 2021, 1-2 adult snakeheads have been found in Reservoir Pond in Canton each summer. Experts at Mass Wildlife think it’s due to someone growing them to size in an aquarium and then tossing them into the pond. Recently, they found young-of-year fish, which suggests they might be breeding.
Snakeheads are an invasive species in Massachusetts. Possession and liberation of snakeheads are both illegal in Massachusetts. Transferring exotic fish into local waterways can cause a host of problems, including competition with native species and spread of disease.
From Mass Division of Fisheries and Wildlife—
During its routine fisheries sampling work, Mass Wildlife has visited over 7,900 locations statewide, documenting over 950,000 fish records since 1998 and has not captured any other snakeheads.
“While we are fortunate that snakeheads have not taken hold here in Massachusetts, this recent discovery highlights the need to focus on monitoring, education, and enforcement efforts to prevent the introductions of exotic species,” said Todd Richards, Mass Wildlife Assistant Director of Fisheries.
Live fish may not be transported in Massachusetts without a permit, and liberation of all fish, including aquarium trade fish, into the wild in Massachusetts is prohibited without a permit from Mass Wildlife.
Resource managers are concerned about the potential for snakeheads to reproduce and become established as a significant component of the fish community as a top predator, as they have in other states such as Maryland.
Massachusetts anglers have played an important role in reporting snakeheads and other non-native species like piranha, pacu, and other escapees of the aquarium trade and illegal exotic introductions.
Snakeheads will go after bait and lures, and with nearly 200,000 anglers out on the water, the fact that so few have been caught in the Commonwealth is reassuring.
Anglers may confuse snakeheads with other native species like bowfin (see image on poster for identification details).
Anyone who captures a fish that can be confidently identified as a snakehead should keep the fish, kill it, and report it to Mass Wildlife by emailing mass.wildlife@mass.gov or calling (508) 389-6300.
Mass Wildlife encourages anglers who are less certain about the species of fish they have caught to send photos showing various angles of the fish. Under no circumstance should a suspected snakehead be transported to another location until identification is confirmed.
Fish Kills
From Mass Division of Fisheries and Wildlife–
The sight of dead and dying fish along the shores of a favorite lake or pond can be distressing and trigger concerns about pollution. Fish do act as the “canary in the coalmine,” so it’s natural to think a fish kill is an indicator of a problem with human caused pollution. However, the vast majority of fish kills reported are natural events.
Natural fish kills are generally the result of low oxygen levels, fish diseases or spawning stress. Depletion of dissolved oxygen is one of the most common causes of natural fish kills.
As pond temperature increases, water holds less oxygen. During hot summer weather, oxygen levels in shallow, weedy ponds can further decline as plants consume oxygen at night.
This results in low early morning oxygen levels that can become critical if levels fall below the requirement of fish survival.
In addition to reduced oxygen levels, late spring and early summer is when most warm water fish species, such as sunfish (bluegill, pumpkinseed, largemouth bass) begin to spawn.
At this time, large numbers of these species crowd into the shallow waters along the shore vying for the best spawning sites. These densely crowded areas become susceptible to disease outbreaks, especially as water temperatures increase.
The result is an unavoidable natural fish kill, usually consisting of one or two species of fish.
To report a fish kill:
Contact the Environmental Police Radio Room anytime at 1-800-632-8075 or email the Neponset Stormwater Hotline at stormwater@neponset.org or give us a call at 781-575-0354 x 300. If we can’t solve the problem or answer the question on the spot, we will relay it to the appropriate agency for further action.
When a caller reports a fish kill, a Mass Wildlife fisheries biologist determines if the kill is due to pollution or is a natural event. Generally, pollution impacts all kinds of aquatic life, therefore the most important piece of evidence for the biologists is knowing the number of fish species associated with the fish kill.
Fish kills in which only one or two species are involved are almost always a natural event. When it is likely a fish kill is due to pollution, Mass Wildlife notifies the Department of Environmental Protection (DEP). DEP takes the lead on a formal investigation which includes analysis of water and fish samples to determine the source of pollution. Mass
Wildlife provides DEP with technical assistance by identifying the kinds and numbers of fish involved.
