Originally published by The Mamaroneck Review
By Andrew Dapolite
Over the past few weeks, hundreds of dead fish have washed ashore in Mamaroneck Harbor and the surrounding waterfronts, raising water safety concerns amongst beachgoers.
However, in a statement emailed to residents and business owners on Aug. 29 in response to numerous inquiries, the village of Mamaroneck attempted to squelch apprehensions by offering a few theories for the massacre. Ideas ranged from naturally occurring conditions such as recent high temperatures, to anthropogenic influences such as an algae bloom triggered by fertilizer entering upstream storm water drains.
Harbor Island Park and local beaches, which are routinely monitored by the Westchester County Department of Health, have remained open to swimmers throughout the past few weeks.According to the village’s statement, “fish kills generally occur in warmer weather when algae growth increases, then dies off and is consumed by decomposing organisms… subsequently lowering the oxygen levels in the water that fish need to breathe.”
Lauren Amato, a Harbor Island Park employee, said that she observed workers removing dead fish from the shoreline beginning in mid-August.
“It was not just one or two,” she said. “It was the entire shoreline. There had to be over 50 fish. It was crazy.”
While the site of the dead fish has come as a shock to some, Dan Catalano, owner of the store Harbor Island Bait and Tackle on East Boston Post Road in Mamaroneck, said it’s just something you have to deal with.
“It doesn’t happen every year and it does not affect the sport of fishing at all,” he said. “The water is still clean. This time of year, people are still catching porgies, fluke and summer flounder.”
Catalano says that the worst complaint he has heard has been the odor caused by fish rotting along the shoreline.
“It smells a lot like sewage,” he added.
Peter Linderoth, water quality program manager for Save the Sound, an environmental nonprofit organization with offices in Mamaroneck, told the Review that the situation is unfortunately not unusual.
“The fish we are seeing in the harbor are Atlantic menhaden, commonly known as bunker,” Linderoth said. “They are a schooling fish and their numbers have been increasing in [the] Long Island Sound over the past few years. If a large school comes into an embayment, that’s already at a point where the dissolved oxygen is low; the fish are very susceptible to basically suffocating.”
Linderoth largely agreed with the village’s assessment that natural causes such as the warm temperatures are contributing to the fish kills, but also stressed that excessive use of inorganic fertilizers on local area golf courses, park grounds and even residential yards could be an additional culprit.
Linderoth further explained that fertilizer can enter the harbor through streams, groundwater and storm water drains, sometimes resulting in unsustainable levels of nutrient pollution. According to Linderoth, nutrient pollution does not necessarily make the water quality unsafe for people; however, it can sometimes lead to toxic algae blooms, which affect the food we eat.
Linderoth also did not rule out the possibility that other bays and harbors along the Long Island Sound could be experiencing similar events despite an overall healthy report card for the large majority of the estuary.
Save the Sound is currently in the process of sampling the dissolved oxygen in Mamaroneck Harbor in order to see if any reductions can be made to protect marine life, which Linderoth believes is not limited to the bunker that live at the bottom of the food chain.
Caren Halbfinger, public affairs director for the county health department, said that despite the fish kills, Long Island Sound remains in excellent condition.
“We have not had any beach closures this year other than preventive because of the amount of rainfall,” she added.