The decomposing carcass of a leatherback sea turtle with severe gashes indicative of a vessel strike was found washed up on Fuller street beach in Edgartown earlier this week, experts at Felix Neck Wildlife Sanctuary confirmed.

This is the third leatherback carcass found on Vineyard shores this year. The previous cases were on State Beach in early summer and on West Chop in mid-September.

Leatherbacks are the world’s largest species of sea turtle. They can be found in waters across the globe and migrate north from the Caribbean during the late-summer and fall months to feed on gelatinous substances, like jellyfish.

Suzan Bellincampi, executive director at Felix Neck, said in an email to the Gazette that “the carcass is so decomposed that we can’t learn much about it.”

However, Ms. Bellincampi said Felix Neck volunteer Marshall Katzen was able to get an approximate straight carapace length measurement of 137 centimeters. Ms. Bellincampi said this size indicates that the leatherback “was probably a sexually mature turtle, or almost to that length/age.”

In her email, Ms. Bellincampi said the leatherback carcass had “probably been floating in Nantucket Sound for over a month” decomposing. Because of the decomposition, Ms. Bellincampi said a full necropsy was not possible. The leatherback’s tail is also absent from the carcass, leaving the wildlife experts unable to determine the sex of the sea turtle with certainty.

Ms. Bellincampi said after a report was taken, Mr. Katzen applied green spray paint to the carcass to alert other reporting parties that a response had been made should the carcass wash back out to sea and wash up elsewhere.

Ms. Bellincampi asks that anyone who finds a sea turtle washed up on shore to call the sea turtle response number at 508-349-2615.