Fort Pond Algae Possible Culprit in Dogs’ Illness

An incident early this month in which two dogs that swam in Fort Pond in Montauk experienced subsequent gastrointestinal illness is raising questions about the water body’s ecological wellness and whether or not a monitoring program should be implemented.

Christopher Gobler of Stony Brook University, who heads a water-quality testing program for waterways under jurisdiction of the East Hampton Town Trustees, wrote to town, Suffolk County, and New York State Department of Environmental Conservation officials on July 8 to report on an inquiry from the county’s Department of Health Services. Fort Pond, like other waterways in Montauk, is not under trustee jurisdiction.

Analyses of the pond’s water, Dr. Gobler wrote, “showed moderate levels of algae, but relatively low levels of blue-green algae,” or cyanobacteria, a bloom of which caused the trustees to close Georgica Pond in East Hampton to the harvesting of crabs and other marine life for much of last summer. “There was, however, a mix of the types of blue-green algae that are known to produce toxins including microcystis and some diazotrophic cyanobacteria,” Dr. Gobler wrote. Microcystins, a class of toxins produced by some freshwater cyanobacteria, can cause serious damage to the liver.

Dr. Gobler did not assert a conclusive link between the algal bloom and the dogs’ illnesses. Given a multi-day lag between the incident and the sampling, and temporal patterns of such blooms, he said, it is possible that the algae were more plentiful when the dogs were in the pond.

Kim Shaw, the town’s director of natural resources, wrote in an email yesterday that samples from Fort Pond, as well as Stepping Stones Pond in Montauk, are being taken to Dr. Gobler’s lab in Southampton.

On Tuesday, Stephanie Forsberg, the assistant clerk of the town trustees, told her colleagues that the level of cyanobacteria in Fort Pond did not warrant a public health alert, and that the dogs may have been in an isolated area of high concentration. She also reported, however, a worrisome macro algal bloom, or seaweed, in Georgica Pond, where a dog that had contact with its water died in 2012. The bloom is worse than what was measured at this time last year, Dr. Forsberg said, and has caused a drop in dissolved oxygen and, consequently, isolated fish kills.

  “We are talking about the possibility of removing it,” Dr. Forsberg told her colleagues, “but it’s not going to happen this season.” A D.E.C. permit would be required for its removal, something she said would be discussed with Dr. Gobler. “We have to be careful, and see if this macro bloom leads to other problems.” 

Because Fort Pond is neither under trustee jurisdiction nor is a county bathing beach, it is not routinely tested at Dr. Gobler’s lab. “Were there a mechanism for samples to be delivered to my lab in Southampton,” he wrote, “we could accommodate a general evaluation of blue-green algae.”

Dr. Forsberg seconded that statement. “If the town wanted to expand this and test areas in Montauk — we’ve mentioned this casually before — it might be worth doing” in areas where human and animal health is a concern, she said.