A bloom of brown algae, known commonly as “brown tide,” has once again stained the waters of western Shinnecock, Quantuck and eastern Moriches bays the color of light-and-sweet coffee.
The infamous brown tide, which wiped out shellfish and marine vegetation across much of Long Island between 1985 and 1995, has been a persistent problem in the stretch of enclosed bays between the Ponquogue Bridge in Hampton Bays and the area just west of the Quogue Canal. It has not been observed in any significant density in the eastern half of Shinnecock Bay or the Peconics, where it did its worst damage in the 1980s.
Scientists from Stony Brook University, who have been studying the brown tide blooms annual recurrences, noted that the algae is also absent from the Great South Bay. They have credited the lack of brown tide in that area to the creation of a new inlet on Fire Island during Hurricane Sandy in October. The added flushing of fresh ocean water appears to keep the algae from gaining a foothold and blooming at great densities.
It is a lack of such flushing that the same scientists have long pointed to as the reason the brown tides have remained so persistent in western Shinnecock and eastern Moriches bays, where the tidal movements through the respective nearest inlets have little cleansing effect.
“The combination of poor flushing and intensive nitrogen loading into the eastern Moriches-western Shinnecock Bay region makes it highly vulnerable to algal blooms,” said Christopher Gobler, Ph.D., a professor at Stony Brook’s School of Marine and Atmospheric Sciences. “We had hoped that the cooler spring and the efforts of the Shinnecock Bay Restoration Program to restock filter feeding shellfish in the bay might restrict this year’s bloom.”
Dr. Gobler and other Stony Brook scientists began a multi-year effort, funded by a private endowment, to boost the number of shellfish in the western half of Shinnecock Bay in hopes that the shellfish, which eat algae, may keep harmful blooms at bay. In addition to the brown tides in summer, western Shinnecock has seen blooms of a red algae species each of the last three springs that has forced the closure of shellfishing beds because the algae is toxic to humans. Officials do not close the bays to shellfishing when brown tides are observed, as the algae do not pose a threat to humans.
In recent years the brown tides have typically emerged in either late May and early June, and persisted through the late summer and early fall.