Thursday, August 10, 2017

Dead seabirds washing ashore on New England beaches

            Walking on the beach at the north end of Block Island last month, Matt Schenck stumbled upon two dead and decomposing seabirds, which the avid birdwatcher identified as great shearwaters. While gulls of various species are commonly found dead on local beaches, shearwaters are an extreme rarity.
            Except this year.
            Hundreds of great shearwaters have turned up dead on beaches on Long Island and southern New England this summer, and no one seems to know why. In addition to the birds on
Dead great shearwater on Block Island (Matt Schenck)
Block Island, birders and biologists have reported dead shearwaters on Rhode Island beaches in Tiverton and Charlestown.
            Shearwaters spend most of their lives far out to sea, where they soar just above the waves as they forage on small fish and other marine creatures near the surface of the water. Four species of shearwater – great, sooty, Cory’s and Manx – are typically seen in Rhode Island waters, though they seldom travel within sight of land. Most breed on remote islands in the South Atlantic.
            According to Josh Beuth, a biologist for the Rhode Island Department of Environmental Management, shearwaters have been observed in large numbers from the shore this year, including from Jamestown, Newport and Point Judith. They have also been seen regularly from the Block Island ferry.
            “There has been an abundance of sand eels in our local waters, which are a forage fish for shearwaters,” said Beuth. “As a result of them being closer to shore than usual, it would be more likely that they’d wash up on shore if they died.”
            While prey may be abundant, some biologists – including Linda Welch, a U.S. Fish and Wildlife Service biologist who studies great shearwaters off Cape Cod – have noted that many of the dead birds are juveniles that have been thin or emaciated, suggesting that the birds have starved.
            The dead birds began to show up on beaches in late June, which is about when they should have arrived along the East Coast after their long migration from their breeding grounds in the South Atlantic. By then they were likely stressed and tired and hungry, which may have made them susceptible to any number of potential sources of mortality.
Wildlife pathologist Joe Okoniewski examined some of the dead shearwaters found on Long Island beaches, and he told the New York Times that the birds were not only thin but anemic. “The big mystery is: Why are they thin? On the surface, it looks like you know what happened – they starved,” he said. “But when you ask why, it becomes much more of a mystery.”
It is especially mysterious if prey is seemingly abundant, as it has been this summer in Rhode Island waters.
Robert Kenney, an oceanographer at the University of Rhode Island’s Graduate School of Oceanography, speculates that toxic algae from red tides may be playing a role in the bird deaths. He said that a number of northern gannets, another species of seabird, have been found dead on Cape Cod beaches this summer. The only difference, he said, is that they are “in good condition, except for being dead.” He thinks that toxic algae may have also contributed to the deaths of some of the numerous whales that have been found dead along the East Coast and in the Gulf of St. Lawrence this year.
Among those trying to find an answer is Julie Ellis, director of the Seabird Ecological Assessment Network at the Tufts University Veterinary Medical Center, which uses volunteers throughout the Northeast to regularly walk beaches to collect dead birds for study. She is reaching out to a number of animal diagnosticians throughout the region in hopes that together they can come up with a consensus of what is causing the shearwater deaths. She hopes they will have an answer next month.

This article first appeared on on August 10, 2017.


  1. Whenever I hear about juvenile seabirds starving to death, I automatically think of plastic pollution in the ocean. Of course, based on the condition of the bird in the photo, it looks like it would be readily apparent if the bird had a belly full of plastic pieces. And it might or might not explain the anemia. I just know that shearwaters are one of the species that are vulnerable to mistakenly feeding their young plastic. The film A Plastic Ocean has quite a lot of about the work of Dr. Jennifer Lavers; she examines the stomach contents of dead shearwaters and it's astonishing how plastic in our oceans is contributing to their mortality. Do you think you'll post/publish a follow-up once the cause of death for these birds is determined? I am very interested in the outcome of this research.

  2. Thanks for writing. I'll do my best to track down the answers that the researchers come up with and post about it again. I'm also interested in the plastics issue as it relates to sea turtles. I've heard that most necropsies on leatherback turtles find balloons and other plastics in their digestive system. I hope to write something about that, too.

    1. Yes! That is another important piece of the plastics issue. Balloon releases (intentional and unintentional) are a huge threat to wildlife, both on land and in the sea, and pose other hazards as well. I've been following for a long time and they're doing a lot of good work to raise awareness around this issue. Looking forward to learning what you discover about the shearwaters as well as future posts about plastic in the ocean.