Saturday, April 07, 2007

A Barnacle Goose Gets Our Local Birders Excited

A Barnacle Goose spent a few days in Vernon and Hinsdale last week. The Barnacle is a fairly common European goose which winters in the British Isles and northwestern Europe and breeds on arctic islands and coasts, including Iceland and Greenland. It is a rare vagrant to North America, and like most rare vagrants, precipitates “the chase” among birders. For our local birders, the Barnacle was a refreshing change of pace; they did not have to drive hours chasing a rare bird sighting. Instead, birders from hours away came here.

The Barnacle Goose was first sighted on Sunday on the Connecticut River above the Vernon Dam among several thousand waterfowl who were night roosting on the partially open waters. Mid-day Tuesday, I walked in to the bluff overlooking the roosting area on the New Hampshire side. It was a delightfully mild, sunny day. There were a couple thousand Canada Geese, and a variety of ducks, aggregating another thousand or two. I spent two hours enjoying the sun, sitting in the grass, and scanning the flocks. I did not find the Barnacle Goose. Near sunset, when even more birds had arrived at the night roost, other birders found the Barnacle Goose strutting across the ice.

I tried again the next day. Thousands of geese were feeding during the day in old cornfields along Riverside Road in Vernon. After about 45 minutes of unsuccessfully searching the flocks, a sharp young birder came walking down the lane and joined in the search. We moved about carefully, trying for angles which would allow us to see over the dips in the fields. Something spooked the geese, and a thousand or two birds roared into flight. But they did not depart. After whirling over the corn stubble, they gradually settled down. As they were doing so, the sharp young eyes next to me picked out the Barnacle Goose in flight, but lost it when the bird settled among the mass of Canada Geese.

The flock took flight a second time, and he picked it up in flight again. This time when the Barnacle returned to the ground, it was atop a rise and in view. Most of the time, the Barnacle was resting, with its head tucked. But it also stood erect so that we could see its white face, black neck and breast, the sharp contrast with the white belly contrasting with the gray back and wings. We could compare its size with the larger Canada Geese.

A few years ago I went chasing after a Barnacle Goose in Ipswich, Massachusetts. I chose the day after it was last reported, although I did not know that at the time. A couple of weeks later, I saw a Barnacle Goose. It was with a small group of native and exotic waterfowl meandering around a small pond at the Philadelphia Zoo. Obviously, that Barnacle was not a bird which I could count, but it illustrates the problem with some sightings of rare birds and with the Barnacle Goose (a popular bird in avian collections) in particular: Is the rare bird of wild origin, or is it an escapee?

The question arose immediately with the Barnacle Goose in Vernon/Hinsdale with an interesting and informative discussion on the VTBIRD listserve. In general, the decision of most Bird Record Committees has been to reject reports of the Barnacle Goose, or as in the case of the Vermont committee to label it “accepted origin unknown.”

This past history led one of the active participants in the discussion to suggest that bird record committees have gotten themselves into an unscientific bind; it is almost impossible to prove that an individual bird is a wild bird or an escapee. To reject the Barnacle Goose out of hand means that much behavioral evidence, migratory patterns, and documented vagrancy must be ignored.

Our Barnacle Goose turned up during the peak of waterfowl migration. The flocks were moving slowly northward as the ice went out of the river. Two days after I saw the barnie, most of the geese had gone. The Barnacle was with wild, far north nesting geese including many of the “lesser” subspecies of Canada Goose, and several each of Cackling Goose, Greater White-fronted Goose, and Snow Goose. With all other geese in the flock, it was nervous, taking wing with the masses on a whim. Wariness toward humans was especially evident. Even from several hundred yards away, the geese were alert to human movements. All of these factors suggest a “wild” origin.

In addition, those who were able to observe the Barnacle Goose more closely could see no signs of captivity, such as feather wear, leg bands, or unusual behavior from a bird unaccustomed roaming free.

The Barnacle Goose nests in northeastern Greenland, Iceland, and northern Norway. So does the Pink-footed Goose, a species that is rarely kept in captivity, and that in recent years has been reported in the Northeast with some regularity. The Northeast is also well outside of the normal migratory route for Ross’, Cackling, and Greater White-fronted Geese, but these species appear regularly in small numbers. In other words, vagrancy is not unexpected among arctic nesting species. The populations of many of these geese has increased in recent decades, which also means that increased vagrancy might be expected.

For the Barnacle Goose, which seems to cause particular consternation to bird record committees, there is hard evidence (that is, proof) that they occasionally stray to North America. In the fall of 2005 along the Ottawa River in Ontario, a hunter shot a Barnacle Goose with a leg band. The goose had been banded in November, 2004, as a juvenile male (first winter bird) in Scotland. One year later the bird strayed to North America where he inadvertently contributed to the current discussion.

This was not the first occurrence of definitive Barnacle vagrancy. In the fall of 1981 a Barnacle Goose was shot in Newfoundland which had been banded in July, 1977, on Spitsbergen, Norway.

On the other hand, an old-timer who entered the discussion remembered a pair of Barnacle Geese which were released, or escaped, at Grand Manan Island in 1990, produced four offspring and wintered in 90-91 in Nova Scotia and Massachusetts. He opined that such an incidence raises doubt about observations for a long time afterward.

Two state bird record committees will be evaluating the Barnacle Goose seen last week in Vernon (Vermont) and in the Connecticut River (New Hampshire). Vermont has several records of the Barnacle Goose, all with some qualification. If accepted, the Barnacle Goose would be a first record for New Hampshire. The weight of the discussion seems to come down on the side of this Barnacle Goose being a genuine wild bird which went astray - a true vagrant.

However, just suppose that one of the record committees accepts the Barnacle Goose, and the other rejects it, or qualifies its acceptance. There’s a conundrum.

For a couple of hours on a couple of delightful spring days, I went looking for the Barnacle Goose. I saw Killdeer running through the fields, hundreds of Horned Larks swirling about, thousands of blackbirds darkening tree tops, robins rattling across lawns, ducks diving in newly open ponds and foraging across old river ice. The sun was warm. The wind was brisk. The birding was good. The Barnacle Goose made it just a little bit better.

Photos of Barnacle Goose in open water and on the ice in the Connecticut River just above the Vernon/Hindale Dam. Photos were taken by Terry Wright who was the first to find the goose and post the sighting on the VTBIRD listserve. Thank you Terry for permission to use your photos.

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