Wednesday, January 4, 2017

Rare greylag goose stirs local birder debate

            The observation of a greylag goose in Watchemoket Cove in East Providence has birdwatchers rushing to the pond adjacent to the Metacomet Country Club to try to catch a glimpse of the rare species. But it has also caused an intense debate over whether it’s a wild bird and, therefore, one that birders can add to their Rhode Island bird list.
Tan and white birds with an orange beak and legs, wild greylag geese have only been recorded in the United States a handful of times, including one record from Connecticut in 2009. As a result, the small parking lot on Veterans Memorial Parkway is often full as local bird enthusiasts search for the goose or wait for it to arrive for its near-daily visits to the site.
Greylag goose with Canada geese, by Alan Strauss.
Native to Europe and Asia, the species has been domesticated and is sometimes found on farms and in aviary collections. These birds occasionally escape captivity and take up with their wild cousins, like the large flocks of Canada geese with which the East Providence bird has been traveling.
The debate over whether the local goose, which was first reported on December 20, is wild or domestic will eventually be settled by the Rhode Island Avian Records Committee, but in the meantime, there is much discussion taking place online about its origin.
On the Facebook group Rhode Island Birders, Andy Boyce argued that there has been an increasing and well-documented pattern of geese that breed in Greenland – greylags breed in nearby Iceland – showing up on the northern coast of North America in the late fall and winter. “This pattern is totally plausible given what we know about errors that birds make during migration,” he wrote, noting recent New England records of barnacle geese and pink-footed geese, which breed in eastern Greenland. “There are very few accepted records of greylag goose…[but] this certainly looks like a good one. Go out and see it!”
Dan Berard, vice president of the Ocean State Bird Club, responded with a 1,000-word treatise acknowledging Boyce’s arguments and pointing out that the East Providence bird looks “superficially” like a wild bird and it does not have a band around its leg, which many domestic birds do. But he also wrote that New England appears to have more escaped domestic waterfowl than other regions, and greylag geese are less prone to wandering out of their normal range than other geese.
“To me,” he concluded, “nothing so far proves this to be more than a potential vagrant greylag, and due to the ingrained migratory patterns, it is incredibly unlikely.”
The process of deciding whether the bird is wild or domesticated can be a lengthy one. It took five years for the Avian Records Committee of Connecticut to issue a decision about the greylag observed there.
The Rhode Island Avian Records Committee – whose members are Robert Emerson, Rachel Farrell, Richard Ferren, Shai Mitra, Chris Raithel, Scott Tsagarakis and Doug Wilson – will gather photographs of the bird and send them to experts in Europe who observe the birds regularly.
“The question will be the bird’s provenance,” said Farrell. “We will never be able to tell exactly where it came from. Unless someone gets a DNA sample, we’ll never know that answer. But we’ll have to look at a lot of the circumstances -- where is it hanging out, what type of birds is it with. There’s a lot of work to do.”
The committee will also contact all of the known waterfowl collectors in the region to see if they lost a greylag. Farrell said that many of the collectors are often not particularly forthcoming with that information.
Rhode Island often has wild geese from other parts of the world turn up in the winter. Canada geese are common year round, and good numbers of brant – a smaller and darker species that prefers coastal waters – spend the winter in the state. A few snow geese, white birds with black wingtips, stop in the state every year as they migrate from Canada to the Mid-Atlantic States. And birders occasionally report a cackling goose, Ross’s goose or greater white-fronted goose, all western species that often wander far from their usual range. In the winter of 2007, seven species of geese could be observed on Aquidneck Island on a single day, including three pink-footed geese and a barnacle goose.

This article first appeared on EcoRI.org on January 4, 2017.

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