The New York State Department of Environmental Conservation (NYSDEC) keeps careful tabs on blue-green algae (BGA) across the state and the Gobler lab has been designated as its downstate facility for monitoring BGA and thus receives samples from dozens of locations through the year and more than a dozen sites weekly. As a reminder, BGA are a serious concern as they can synthesize toxins that can poison animals or humans. BGA blooms are presently occurring through multiple sites on the East End and in NYC, including Central Park Pond. There are more than seven sites with BGA blooms across eastern Suffolk County and on Friday, Wainscott Pond was added to the list. Located ~2,000 ft west of Georgica Pond, it shares many of the same properties including nutrient loading sources. The very major difference between the two sites right now is the salinity. The salinity of Wainscott Pond is zero; it is a freshwater body which is the environment BGA thrive within. The salinity of Georgica Pond is presently 16; too high for the growth of BGA. This elevated salinity is due to the fact that Georgica Pond was open to the ocean from January through June this year.

The complete list of locales experiencing BGA in NYS can be found here.
http://www.dec.ny.gov/chemical/83310.html