Around the Island

Mashomack Musings: Tracking menhaden

As offshore waters slowly warm with the seasons, many fish return to our estuaries and bays. One iconic fish, the Atlantic menhaden, sometimes called bunker, has made a recent return. But there’s a problem — die-offs and irregular swimming behaviors are being reported.

Menhaden are small but mighty, the small fish that big fish need to eat, a fact that’s earned them the designation “the most important fish in the sea.”

Able to live up to 12 years, menhaden lay their eggs out in the open water. Once these eggs hatch, the young fish return inshore to coastal waters to grow. Menhaden are filter feeders who take in abundant, microscopic plankton. You may notice schools of them swimming with their mouths open wide as they filter in these small creatures to consume.

Although many of us are used to seeing menhaden swimming in schools around the Peconics and other local bays, in recent months many have been seen displaying “irregular swimming behaviors (circling/twirling)” or found dead and washed up along the shore according to The New York State Department of Environmental Conservation. The DEC has been investigating and tracking these events since last fall.

As with any disruption or die-off in a marine ecosystem, water quality always gets the first look. However, in this case, scientists are turning toward another cause, a bacterium known as Vibrio that occurs naturally in coastal waters. The DEC says that this bacterium is not “typically known to be harmful to humans” but to treat any dead or dying fish you may encounter with caution and wear protective gloves if you need to remove them from your yard or stretch of beach.

Fishing season has gotten underway. And because popular sport fish such as bluefish, weakfish and striped bass depend on menhaden as their main food source, many of us are wondering whether it’s safe to eat sport fish species who’ve consumed menhaden affected with Vibrio. The good news, according to the DEC, is that bluefish, weakfish and stripers are still safe to eat. So happy fishing, everyone.

Mashomack is owned and operated by The Nature Conservancy, a global environmental nonprofit working to create a world where people and nature thrive. Our mission is to conserve the lands and waters on which all life depends. To learn more, visit nature.org