The state is investigating the death of a humpback whale that got entangled in a fishing net and washed up on shore just east of Gilgo Beach, a representative of the Riverhead Foundation for Marine Research and Preservation said Thursday.

With humpbacks on state and federal endangered species lists, the state Department of Environmental Conservation is investigating this as a "fisheries incident," said Kimberly Durham, the foundation's rescue program director. Once the federal government returns to full operation, the National Oceanic and Atmospheric Administration will also get involved, she said.

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Found by an early-morning surfer Tuesday, the animal, a female weighing around 20 tons, displayed wounds and trauma associated with the net and was also on the thin side, Durham said. The animal, the second humpback found dead on Long Island this year, was buried at the site with the help of state Parks Department heavy equipment, she said.

While not really humpbacked, the animals appear to be when they arch "in preparation for a deep dive," according to the DEC.

Known for their courtship "songs" and "acrobatic antics," they're described as "chunky, heavy-bodied," weighing in at 30 to 40 tons, and distinguished from other large whales by their dorsal fins and "very long white flippers," the DEC said.

The public can report dead or stranded marine animals at the Riverhead Foundation's 24-hour-hotline: 631-369-9829.