On YouTube: HABs A Summer of Discontent in Long Island's Coastal Waters
Harmful Algal Blooms - News



SBU scientists have completed their assessment of water quality in Long Island’s estuaries in 2021, and the news is not good. From June through October, every major bay and estuary was afflicted by toxic algae blooms and oxygen-starved, dead zones.

New 2021 Map Shows Dead Zones and Toxic Tides Blanketed Coastal Waters; Inundated with Rainfall from Tropical Storms

— Filed by Stony Brook University News 

Stony Brook, NY, October 8, 2021 - Scientists at Stony Brook University have completed their assessment of water quality in Long Island’s estuaries in 2021 and the news is not good. During the months of June through October, every major bay and estuary across Long Island was afflicted by toxic algae blooms and oxygen-starved, dead zones. Excessive delivery of nitrogen from onsite wastewater has been cited as the cause of these disturbing events. The news was announced  on October 7 at the Patchogue waterfront by Christopher J. Gobler, Ph.D., Endowed Chair of Coastal Ecology and Conservation at the School of Marine and Atmospheric Sciences (SoMAS) at Stony Brook University.   

“It began with mahogany and brown tides in June and ended with a harmful rust tide that continues today across eastern Long Island,” said Gobler. “In between, a record-setting two dozen low oxygen dead zones were identified from Great Neck to East Hampton, over 20 lakes and ponds were affiliated with toxic blue-green algae blooms, and fish kills across another half dozen sites. This has become the new normal as Long Island deals with a dual assault of climate change and excessive nitrogen loading.”


Left to Right: Christopher J. Gobler, Endowed Chair of Coastal Ecology and Conservation Stony Brook University; Peter Scully, Deputy Suffolk County Executive; Adrienne Esposito, Citizens Campaign for the Environment; Kevin McDonald, The Nature Conservancy. Credit: The Gobler Laboratory at Stony Brook University

The summer of 2021 stood out as having nearly double the average rainfall total, with more rainfall coming during each individual storm. This may be the new normal as scientists predict Long Island will experience more precipitation in total in the future due to climate change. This excessive rainfall brings more nitrogen loading from land to sea, fueling harmful algal blooms and dead zones. For example, following tropical storms Henri and Ida, a mild rust tide expanded and intensified all across the east end of Long Island and the dead zones expanded across Long Island Sound and elsewhere.

Excessive nitrogen coming from household sewage that seeps into groundwater and ultimately, into bays, harbors, and estuaries or, in some cases, is directly discharged into surface waters, is a root cause of these maladies. Suffolk County and Nassau County completed ‘subwatershed studies’ last year that identified wastewater as the largest source of nitrogen to surface waters. Excessive nitrogen stimulates toxic algal blooms that can, in turn, remove oxygen from bottom waters as they decay. Policies to mitigate nitrogen loading such as upgrading onsite septic systems are, therefore, the best defense against these impairments, explained Gobler. 

The outbreaks of blue-green algal blooms in 2021 is a concern for both human and animal health. For the past six years, Suffolk County has had more lakes with blue-green algal blooms than any other of the 64 counties in New York State, a distinction that is likely to be repeated in 2021. Blue-green algae make toxins that can be harmful to humans and animals and have been linked to dog illnesses and dog deaths across the US and on Long Island.

Of equal concern is the widespread nature of dead zones across Long Island.  Dead zones are regions of low or no oxygen. The NYS Department of Environmental Conservation indicates that marine waters should never have less than three milligrams of dissolved oxygen per liter to allow fish to survive.  Through the summer, more than two dozen sites across Long Island did not meet this criterion, and in several cases, fish kills occurred. 

“The data reveals that many sites are not suitable habitats for sustaining fish and shellfish,” added Gobler.

The occurrence of these events such as brown tide and rust tide, have led to the collapse of critical marine habitats such as seagrass, major fisheries on Long Island such as scallops and clams, and the coastal wetlands that help protect waterfront communities from the damaging impacts of storms.  Groups such as The Nature Conservancy have been working for more than a decade to revive and restore these habitats and shellfish but have been challenged by algal blooms such as those witnessed during the summer of 2021.

“It has gotten to the point that we have to watch News 12 each week to see where it is safe to swim or fish,” said Carl LoBue, Senior Scientist for the Nature Conservancy.  “The research findings are conclusive. We know how to fix this and it’s time to act. The longer we wait to fix our water quality problems, the longer it will take and the more expensive it will be.”

The report on the 2021 summer was compiled by Dr. Gobler, whose lab group has been monitoring and sampling Long Island’s waters on a weekly basis every summer since 2014.  Data was also generated by the Long Island Sound Study which is funded by the US Environmental Protection Agency and the NYS Department of Environmental Conservation.  


Water quality impairments across Long Island during the summer of 2021. Credit: The Gobler Laboratory at Stony Brook University

A map generated by the Gobler Laboratory (seen above) shows precisely where on Long Island various algal blooms and low oxygen zones developed during the summer of 2021. Events depicted include algal blooms caused by Prorocentrum causing harmful mahogany tides, rust tides caused by the algae Cochlodinium, brown tides caused by Aureococcus, a red tide caused by Dinophysis, and toxic blue green algae blooms commonly caused by Microcystis.  The map also depicts hypoxic or low oxygen zones which are dangerous to marine life.

The study was supported by the Rauch Foundation, the Chicago Community Trust, and an anonymous donor.


More Info: Related Media Stories and Clips from HABs Press Conference



Filed by News 12 staff

Scientists raise concerns about trend of poor water quality on South Shore, Long Island Sound

Oct 08, 2021 - Scientists and environmental activists are raising the alarm about an increasing trend of poor water quality on the South Shore and in the Long Island Sound.

Those who came out to Patchogue to check out the water say nitrogen runoff is primarily to blame for toxic algae blooms and rust tides that have made the South Shore and Long Island Sound inhospitable for thin fish and shellfish to thrive.

Strong weather events like tropical storms have become more prevalent and increase nitrogen runoff.

Christopher Gobler, a professor with Stony Brook University’s School of Marine and Atmospheric Science, says scientists are predicting storms will become more frequent, which is going to impact more than just fish in the area.

“What that means is the amount of nitrogen going from land to sea is going to increase and continue to threaten our water bodies, our marine life and even frankly, human health,” Gobler says.

Centereach resident Marguerite Mencke says she can see the water issues every time she goes fishing.

“This is our future, this is what our kids are eating, this is what we are eating,” Mencke says. “We want it as clean as possible.”

Scientists say fixing outdated septic systems and getting more homes on sewer systems is one solution to reducing nitrogen in the water.

They have praised Suffolk County’s efforts in starting that process but say there is still a lot more to be done.

Some in the area, however, are worried what the cost will be.

“It will definitely help the environment,” says John Williams of North Babylon. “But for everything there is a cost so how much is it gonna cost me?”

Suffolk will be receiving $230 million in federal funds to help fund sewer projects along the Carlls and Forge River areas.




Environmental Experts Say Long Island Implementing Fixes To Improve Water Quality Following Troublesome Storms

By Jennifer McLogan, CBS 2 News

Patchogue, NY, October 7, 2021 — An annual water quality report has painted a dire picture on Long Island of the challenges facing our region’s waterways.

They include toxic tides, dangerous algae blooms, and turtle and fish kills, CBS2’s Jennifer McLogan reported Thursday.

The quality of the water is the gold that fuels Long Island’s local economy.

“I’m going for snappers, blowfish or anything that wants to bite the hook,” Centereach homeowner Marguerite Mencke said.

Mencke said from fishing to tourism, it’s all dependent on the health of the water.

“The upgrading is so important for the clarity of the water. I mean you don’t realize, ‘Oh, I’m one person, what difference does it make?’ It makes a big difference,” Mencke said.

She has been imploring each of her neighbors who live close to the bay to upgrade their septic systems.

Virtually all the water impairments are driven by rising nitrogen levels, stemming from household sewage.

Dr. Christopher Gobler and his Stony Brook University students discovered every major bay and estuary from Great Neck to East Hampton suffered with toxic algae or oxygen-starved waters this summer. They were made worse by storms Henri and Ida, when polluted runoff discharged into coastal water, killing sea life.

“And what that means is the amount of nitrogen going from land to sea is going to increase and continue to threaten our water bodies, our marine life, and even, frankly, human health,” Gobler said.

“The bad news is these toxic tides are plaguing our waterways. The good news is we have a plan. The better news is we are implementing it,” said Adrienne Esposito of the Citizens Campaign for the Environment.

With homeowner grants and incentives for sewage infrastructure fixes.

“The way we developed in the 1950s and ’60s caught up with us and we can’t do it anymore,” The Nature Conservancy’s Kevin McDonald said. “Suffolk County now is the leading county in the country to reverse and abate this problem.”

Numbers are dropping, but 380,000 homes and businesses here still need to replace their aging, polluting septic systems to keep the water we depend on safe and clean.

Some federal, state and county grants make it possible to replace home septic systems for free.


More Info: Noxious Seaweed a Invasive Threat in Great South Bay

As reported in late October 2021 by Fox News and NBC 4 New York, red seaweed is causing an unusual smell on the South Bay. Both TV stations discussed the issue with Gobler, who first introduced the topic to New York Sea Grant in August 2020's "In Photos, On YouTube: State of the Bays: Noxious Seaweed Among New Threats in 2020"



Foul Smell in Great South Bay is From Decaying Invasive Seaweed

Filed by Jodi Goldberg, Fox 5 News

Stinky Great South Bay — Scientists have pinpointed the source of a foul odor in the Great South Bay.

East Islip, NY, October 18, 2021 - The smell is so potent that it is described as rotten eggs or a sewage spill. But it is neither of those. Instead, scientists have pinpointed the source of the odor in the Great South Bay as an invasive red seaweed. The red tinge in the water is most noticeable on warmer days with a south wind but often no one even knows it is even there.

This foul phenomenon is newer to North America. And this latest outbreak on Long Island is wreaking havoc in the Great South Bay, where the seaweed thrives on high nitrogen and carbon dioxide, according to Dr. Chris Gobler, a professor at Stony Brook University.

"It originated from Japan and it's slowly spreading across the globe," Gobler said. "It likes slightly cooler temperatures, and over the summer as the bay gets warmer, it starts to decay. And come the fall, the decayed seaweed and rotted seaweed smell pretty bad."

Aside from the smell, scientists said decaying seaweed can reduce oxygen in the water and harm sea life. In high concentrations, it can also be dangerous to breathe in.

"At high levels, rotting seaweed can release hydrogen sulfide gas and make people sick," Gobler said. 

Some ways to take action include limiting the use of fertilizer and updating your septic tank.

"Our home values, businesses, and recreational opportunities are dependent on the bay being healthy," Save the Great South Bay's Robyn Silvestri said.

Curbing pollution and sewer runoff now help make sure the bay is healthy for generations to come.



Foul Smell in Great South Bay Is From Invasive Seaweed

Filed by Greg Cergol, NBC 4 New York

East Islip, NY, October 22, 2021 - Red seaweed is causing an unusual smell on the South Bay. 

This aggressively-spreading seaweed, which is native to Japan, poses a threat to Long Island shores like these.

"Wastewater from septic systems stimulates this aggressive seaweed,” said Dr. Christopher Gobler, a coastal ecologist at Stony Brook University’s School of Marine and Atmospheric Sciences.

The seaweed spread in Europe in the 1980s and has been in North American waters for the last decade and a half or so.

“In 2019, we saw a bad outbreak of it spreading on the south shore of Long Island,” said Gobler. “When the seaweed die back, they emit a strong smell of sulfur. But it’s more than a nuisance smell: reports from other countries indicate the gas emitted when it decays can cause health problems including serious lung irritation. Some people affected had to be admitted to hospital intensive care units.”

The spread of this seaweed is propelled by high nitrogen levels. 

“All of Long Island is a watershed,” said Gobler. “The groundwater is our drinking water. Any activity—agricultural, industrial, household—on land affects our drinking water.”

Nitrate in the groundwater has been increasing. More people living on the land means more nitrogen. Nutrients, such as nitrogen from wastewater emanating from antiquated septic systems that are not designed to remove nitrogen, flow into our coastal waters, leading to harmful algal blooms (HABs), releasing biotoxins that threaten humans, livestock, and even pets. HABs become more intense and more toxic with increased nitrogen.


More Info: New York Sea Grant

New York Sea Grant (NYSG), a cooperative program of Cornell University and the State University of New York (SUNY), is one of 34 university-based programs under the National Oceanic and Atmospheric Administration’s National Sea Grant College Program.

Since 1971, NYSG has represented a statewide network of integrated research, education and extension services promoting coastal community economic vitality, environmental sustainability and citizen awareness and understanding about the State’s marine and Great Lakes resources.

Through NYSG’s efforts, the combined talents of university scientists and extension specialists help develop and transfer science-based information to many coastal user groups—businesses and industries, federal, state and local government decision-makers and agency managers, educators, the media and the interested public.

The program maintains Great Lakes offices at Cornell University, SUNY Buffalo, SUNY Oswego and the Wayne County Cooperative Extension office in Newark. In the State's marine waters, NYSG has offices at Stony Brook University in Long Island, Brooklyn College and Cornell Cooperative Extension in NYC and Kingston in the Hudson Valley.

For updates on Sea Grant activities: www.nyseagrant.org has RSS, Facebook, Twitter, Instagram, and YouTube links. NYSG offers a free e-list sign up via www.nyseagrant.org/nycoastlines for its flagship publication, NY Coastlines/Currents, which is published quarterly.

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