The large number of dead birds found on the Island’s shores in June have been confirmed to have died from starvation.
In June, the state issued an announcement suspecting highly pathogenic avian influenza (HPAI) to be killing birds, including “seagulls, ducks, terns, and cormorants,” in Massachusetts’ coastal areas. For several months prior to the announcement, HPAI was detected in other parts of North America, from “Canada to Florida.” The initial suspicion of HPAI being the culprit of the birds’ deaths prompted some Island towns to post warnings online and put up signs for beachgoers. Edgartown animal control officer Kim Andrade reported eight to 15 dead birds washed up on the short beach area of Great Rock Bight Preserve in Chilmark; 31 found on South Beach in Edgartown, 50-plus found between Gay Head and Lobsterville Beach in Aquinnah; and 40 at Lambert’s Cove in West Tisbury. This was brought up briefly during an Aquinnah select board meeting.
However, Chilmark health agent Marina Lent told The Times she heard secondhand that HPAI was not the cause of the bird deaths on the Island. “Apparently, it was due to starvation. No highly pathogenic avian influenza was found,” Lent said. She suggested reaching out to the Edgartown animal control officer, Kim Andrade. Previously, Andrade had referred questions to Edgartown health agent Matt Poole.
Poole confirmed that the state labeled the dead birds they examined as “emaciated.” “We haven’t heard anything of the contrary,” Poole said.
Poole also said many of the misidentified dead cormorants reported by passersby were actually great shearwaters. According to an email he received from BiodiversityWorks founder and director Luanne Johnson, one of the Island wildlife experts who weighed in on the dead bird phenomena, “95 percent of the birds washing up on our beaches” are great shearwaters, most of them juveniles.
“Several of the dead shearwaters were collected from M.V., and other beaches in our region, and shipped to wildlife veterinarians to determine [the] cause of death. None of them tested positive for HPAI thus far. All were emaciated, and the consensus is that they died of starvation,” Johnson wrote in the email.
These deaths are related to the migratory patterns of great shearwaters. According to Johnson, great shearwaters nest in the Southern Hemisphere before migrating north. They spend most of their life at sea, so they are not as susceptible to HPAI compared with the other birds found dead on the state’s beaches. It is uncertain as to why so many dead great shearwaters came up onto Massachusetts shores, but it is not unprecedented. Several “large-scale die-offs” have occurred in the North Atlantic in June during the past decade.
“While this large-scale loss of all of these young birds is certainly very sad, they are still very numerous,” Johnson wrote. Audubon estimates that there is a global population of around 15 million great shearwaters. “The question in many ornithologists’ minds these days is whether these starvation events are occurring more frequently than in the past,” Johnson added.
However, that does not mean there was no HPAI detected from other washed-up bird species off-Island. Johnson wrote that waterfowl and cormorants are the most likely to have HPAI.
“That list includes gulls, northern gannet, terns, crows, ravens, vultures, owls, hawks, bald eagles, and osprey,” she wrote. “HPAI can spread to other animals, and also to humans in rare cases. An example of this is some seals in Maine recently dying from HPAI.”
When asked whether more information has been released, Johnson said there “have not been any follow-up reports.”
“The majority of the birds washing up on our beaches were great shearwaters on the beaches [BiodiversityWorks] monitor,” she said. “I cannot speak to the rest of the Island, but I did not hear anything to indicate substantial numbers of other species.”
Island naturalist Matt Pelikan told The Times great shearwaters’ migratory patterns and habitat caused the uncertainty surrounding the dead birds. “We have very incomplete understanding of the full ecology of great shearwaters and most other pelagic birds. They range over many thousands of miles of ocean, responding to navigational cues that we can barely imagine, and therefore are really hard to study in detail,” Pelikan said.
Neither the Massachusetts Division of Fisheries and Wildlife (MassWildlife) nor the Department of Fish and Game has made a public update regarding the birds, after the first press release suspecting HPAI in June. Danielle Burney, deputy director of the state’s Executive Office of Energy and Environmental Affairs, told The Times in an email that around 40 wild birds found along the Massachusetts coastline were confirmed by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service to have been infected by HPAI.
“Most of these birds were collected in June 2022. Samples were primarily collected from eiders, gulls, and raptors in coastal areas,” Burney said.
Burney confirmed that “many dead birds that were found on Martha’s Vineyard and elsewhere in June 2022, originally thought to be cormorants and later identified as great shearwaters, tested negative for HPAI.”
“Observations of sick and dead birds have substantially declined since peaking in June,” Burney said. “Over the past few months, HPAI has only been detected in coastal areas of Massachusetts.”
Johnson urged people to still “practice extreme caution if you find a sick or deceased bird.” She said people should avoid handling the corpses, and keep pets away from them. Sightings of five or more dead birds in a single location can be reported to the Massachusetts Division of Fisheries and Wildlife at bit.ly/3JIDeIq.