A dead humpback whale washed ashore in Amagansett. This is the 11th whale to wash up in the area.  Credit: Handout

An approximately 25-foot, deceased humpback whale washed ashore Tuesday on the western end of Napeague State Park in Amagansett, according to the Atlantic Marine Conservation Society.

The Hampton Bays-based nonprofit plans to conduct a necropsy Thursday at the ocean beach to find the mammal's cause of death, said Robert DiGiovanni Jr., the organization’s chief scientist and executive director.

DiGiovanni said it’s unclear if the deceased animal will be buried on site or be moved to a different location.

During the necropsy, the organization collects tissue samples, takes measurements and looks for any scarring or injuries.

"Then we put all those pieces together and send out our samples we collect — if we’re able to get them — to our pathologist to have them review," he said.

The conservation society takes the lead on investigating causes of mortality for whales, dolphins, seals and sea turtles for this region, DiGiovanni said.

Rising numbers of humpback whale mortalities have occurred along the Atlantic coast since 2016, resulting in an Unusual Mortality Event declared in April 2017, according to NOAA Fisheries.

DiGiovanni said this whale is the 11th to wash ashore this year in the region where it responds, which can also include waters off New Jersey.

He said this year’s figure is on track for the average of 11-14 the organization has seen since 2016-17. Prior to that, the number was around 1-3, he said.

"Right now, the leading cause for humpback whales appears to be vessel strike and then entanglements to some extent," DiGiovanni said.

Overall, nearly 200 marine mammals and sea turtles have washed ashore this year, he said.

DiGiovanni said the public’s help is crucial and anyone who spots a whale, dolphin, porpoise, seal or sea turtle can report it, even if it doesn’t appear to be in distress. Information is available on the conservation society's website.

Tim Treadwell, East Hampton's senior harbor master, said the whale washed ashore in a remote area of the beach that requires a four-wheel drive vehicle to reach or a walk of about a mile and a half from the nearest access point.

Since the whale landed on the state park beach, the New York State parks department and park rangers took a more active lead at the site compared to town departments if it had landed on a town beach, he said.

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Newsday Live presents a special evening of music and conversation with local singers who grabbed the national spotlight on shows like "The Voice," "America's Got Talent,""The X-Factor" and "American Idol." Newsday Senior Lifestyle Host Elisa DiStefano leads a discussion and audience Q&A as the singers discuss their TV experiences, careers and perform original songs.

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