This observation is likely part of an ongoing marine mortality incident involving dead and dying Atlantic menhaden (Brevoortia tyrannus), also known as bunker, around Long Island, the Hudson River, and extending from Rhode Island to New Jersey. Throughout the region some menhaden have displayed irregular swimming behaviors (circling/twirling) or have been found dead. DEC and neighboring state agencies have been investigating, monitoring, and tracking this event since Fall of 2020.
DEC sent samples of tissue from collected fish to Stony Brook University’s Marine Animal Disease Laboratory and Cornell University to test for a viral infection often associated with the observed, irregular, swimming behavior. New Jersey’s Department of Environmental Protection (NJDEP) also sent samples of menhaden to Pequest Aquatic Animal Health Laboratory. Samples of menhaden collected by both states tested negative for the virus.
Additional investigations of affected fish by NJDEP found internal signs of disease associated with the presence of a Vibrio bacteria in most samples. This bacterium is a possible cause of the mortality event. DEC is working to confirm this with additional samples from fish found in in New York this Spring. Vibrio bacteria are a naturally occurring bacteria in coastal waters that are typically present in elevated concentrations between May and October.
The specific bacterium identified by the NJDEP is not typically known to be harmful to humans. However, as a precaution, DEC recommends treating the situation the same as you would with any dead, wild animal. If you need to come in contact with dead fish to clean them up, make sure to wear appropriate protective equipment, including gloves.
There have been no reports of other fish or wildlife species being impacted by the suspected bacterium causing this mortality event. Menhaden occupy estuaries and coastal waters from northern Florida to Nova Scotia and are an important prey species for a wide range of wildlife and are typically used by humans as bait. It is still safe to eat fish that prey on menhaden. As always, it is recommended that all fish and shellfish be cooked to the proper temperature and fish that are dead or appear sick should not be collected or eaten.
DEC will continue to work with state and regional partners to further investigate this mortality event. As new information unfolds, the DEC will provide information to local governments and the public as necessary. Please continue to report fish kills by email to fishkillmarine@dec.ny.gov or call 631-444-0495 for marine waters or 845-256-3199 on the Hudson River.” – New York State Department of Environmental Conservation