Thursday, January 20, 2011

CORE Blimey!**

The text message from Sam Galick said "core at grsp spot"; complete gobbledegook to most, but birders at Cape May instantly knew that he had found a Common Redpoll. When, just a few minutes later, the next message said "Make that 4 core feeding on goldenrod", I knew that this wasn't just another fly-over, single-observer sighting and I had to find an excuse to shoot over to the beach near Cove Pool. When I got there, Sam was still present and the redpoll count had increased to six! After a while Karl Lukens joined us and we were able to get excellent views of the birds as they fed on the copious amounts of Beach Goldenrod seed.

Common Redpolls choose to winter well north of Cape May in most years, but occasionally their winter wanderings (usually due more to food availability than weather) bring them down to the point. This winter has seen a fair scattering of reports of one to two birds, but almost always involving fly-overs or birds that moved quickly on and didn't stay to be enjoyed by the masses. This time though, this little party allowed close approach and it was even possible to name them to subspecies. These birds were of the more-expected nominate race flammea, a widespread form which breeds in northern birch and spruce forests around the globe, from Alaska eastward to, well, Alaska! There is something of a gap in the range, however, with different races breeding in Greenland and Iceland. The Greenland race, rostrata, has, according to Sibley's Birds of Cape May, been recorded just once at Cape May, with all other birds that could be assigned to race, being considered to be flammea. Greenland birds are typically large and chunky and clearly much browner and more smudgily marked than flammea. They have slightly heavier bills, a larger black bib under the bill and usually far less white on the rump - but (of course!) there are a few birds that seem somewhat intermediate and defy strict classification.

Common Redpoll, Cape May. Ageing and sexing redpolls is notoriously difficult, unless dealing with a full-blown, rose-pink adult male. Birds with no pink below may be adult females, or first-winter birds of either sex. Due to molt timings of the various age-classes, generally the only safe ageing criterion is based on the shape of the tips of the tail feathers. I never really got an ideal look at this one, but it deem seem quite pointed and a little abraded, indicating that it is probably a first-winter bird. [Photo by Mike Crewe].

The same bird as above. Common Redpolls of the form flammea are usually intermediate in every way between the dark, heavy-billed rostrata birds of Greenland and the small-billed, frosty snowballs that are Hoary Redpolls [Photo by Mike Crewe].

One useful fieldmark for separating Common and Hoary Redpolls is the presence or absence of dark shaft streaks on the under tail coverts. The broad-based, dark streak seen here would typically not be found in a Hoary Redpoll (and this photo shows that this is not an easy thing to assess in the field!) [photo by Mike Crewe].

The pink flush on the chest of this individual rules out a first-winter female Common Redpoll, but adult females can be this rosy so we are not much wiser on this one... [photo by Mike Crewe].

This bird has an extensive pink wash on the underparts, extending well down onto the flanks and indicating that it is almost certainly a male [photo by Mike Crewe].

Another look at the same bird as in the last picture; note that the pink flush extends well up onto the face too [photo by Mike Crewe].

These birds were feeding in the scrubby dune area to the back of the beach, just west of the beach cross-over at Mount Vernon Ave.; we would ask anyone going to look for the birds to please stay off the banked ridge at the back of the site (which was put in as part of coastal protection and should not be walked on to avoid un-necessary erosion) and to be sympathetic to the habitat wherever there are coastal plants growing.

**Wikipedia has a page wonderfully titled 'List of British words not widely used in the United States', under which you will find this phrase!!

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