Reporting a Fish Kill

This is how the water front looks today. 25 ft back I could smell the dead fish. At least 8 fish dead at first glance: My husband identified 3 white perch, a pickerel, a bass, yellow perch, and a few kivers. Another neighbor told us he had 9. In all my years here, I never remember it looking this gross.

I called Mass Wildlife as they had just sent out their monthly e-newletter with a blurb on REPORTING FISH KILLS. The dispatcher had a biologist call me within minutes. The biologist, Todd Richards, said it is good to report the kills so that the state can record it and get a history on what is going on. He himself knows Manchaug Pond as he likes to ice fish here. 🙂

He said if the kill is under 100 fish, wait and call the office Monday morning.

Specifically, biologist look at three things: 1. multi species 2. large numbers and 3. if they are still dying, in trying to determine a cause. Talking it through with him, we could eliminate pollution – the yellow stuff is harmless pollen from the white pine trees. (I have a degree in horticulture so I knew that one!) Now the excessive heat is definitely a factor- going from 50-60’s to the 90’s in one day AND he said it comes at a time when the fish are stressed due to spawning. The yellow perch just finished spawning and the kivers (pumkinseeds, bluegills, etc) are in shallow water looking to spawn.

Being the corresponding secretary of Manchaug Pond and always on duty, I asked about our waterlevel… if we are a shallow pond with a mean depth of 13 feet and the lake is down 3 1/2 to 4 feet could this be a factor… He had heard our story with the dam owner lowering the lake and his expert opinion was that this was NOT the time to be changing the water level. He said changes now would effect adults this season and the number of young next season.

Glad I called! Especially in light of the fact the dam owner is still talking about dropping us down this month, even after the DEP ruling, to follow their rule curve.

Now it is your turn to call Mass Wildlife and tell them what you are seeing so they can get a history on Manchaug. Mondays through Fridays between 8:00 am and 4:30 pm, contact Richard Hartley at 508/389-6330. He did ask me where I was located on the lake and how often I am seeing the fish and if they are newly dead.

Also here is the official blurb and subscription info to their electronic newsletter.


With warm weather warming up lakes and ponds, fish kills may be discovered in some bodies of water. 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 warmwater 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.

When a caller reports a fish kill, a MassWildlife 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, MassWildlife 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. MassWildlife provides DEP with technical assistance by identifying the kinds and numbers of fish involved.

To report a fish kill Mondays through Fridays between 8:00 am and 4:30 pm, contact Richard Hartley at 508/389-6330. After normal business hours or on holidays and weekends, call the Fish Kill Pager at 508/722-9811 or contact the Environmental Police Radio Room at 1-800-632-8075.”

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