A warning to Hudson Valley residents was released by the DEC this week after officials finally determined what's been killing so many fish in our area.

Last summer we told you that Riverkeeper was concerned over an extraordinarily high number of dead fish reported throughout the region. The environmental group blamed the issue on pollution in the river and high temperatures that have led to a lack of oxygen in the water. It turns out the real reason may be a bit more complicated than that.

The DEC says they responded to an increase in reports of dead fish, specifically Atlantic menhaden. Large numbers of the species has been discovered dead or swimming irregularly in the Hudson River and other surrounding areas.

The agency sought out samples that were then processed by the School of Marine and Atmospheric Sciences. The tests found bacteria living in both the dead and distressed fish. Vibrio, a naturally occurring bacteria, was discovered in the fish.

The DEC says Vibrio bacteria are commonly found in higher concentrations during warm weather. However, studies suggest that sewage and other pollutants can also greatly contribute to outbreaks of Vibrio bacteria in waterways.

Because the bacteria was found in local waters, the DEC is warning Hudson Valley residents to use precautions when handling the fish. Although Vibrio bacteria are not usually harmful to people in good health, those who suffer from diabetes, liver disease, cancer or are immunocompromised can be at risk if they swim or come in contact with the untreated water.

As a precaution, the DEC says they recommend treating the situation "the same as you would with any dead, wild animal and do not handle without gloves or other protective equipment."

If you spot unusual fish activity, the DEC encourages you to send reports and photos of any dead, dying or irregularly swimming fish in the Hudson River to fishkillmarine@dec.ny.gov. Reports can also be made by calling 845-256-3199.

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