Thursday, November 13, 2008

Bonaparte's Gulls

The garbageheads give gulls a bad rap. Those large, aggressive Ring-billed and Herring Gulls that frequent dumps and fast food outlet parking lots have given the average Joe the idea that all gulls are the equivalent of winged rats. Nothing could be further from the truth. Even the big boys that are prone to dumpster-diving, and here in Ohio that's usually the Ring-billed Gull, are beautifully proportioned and supreme aerialists.

But they lack the graceful good manners and delicate agility of my favorite of this bunch, the Bonaparte's Gull.

On a recent Lake Erie trip, I got to spend a bit of time photographing some bonos at Ashtabula County's Conneaut Harbor. I could watch them all day, and strive for getting that perfect shot. But althought they don't look overtly fast, Bonaparte's Gulls are usually moving faster than one thinks when trying to freeze them on the wing.

Pristine adult Bonaparte's Gull, Chroicocephalus philadelphia, in crisp winter plumage. Birds in breeding finery have solid black heads, as if some jokester thrust them beak first into a vat of ink. The white wing flashes are quite distinctive in any plumage. The common name honors a distant relative of the famous Napoleon Bonaparte, while the scientific specific epithet recognizes the area where the first specimen was secured, Philadelphia.

Here's a youngster, a first-year bird. Note the black terminal band on the tail and the dark bars on the wing. Bonaparte's are two-year gulls: it takes them two seasons to attain full adult plumage. For big gulls like Herring and Great Black-backed, it requires four years to reach adulthood.

This bird was raised in a tree! That's right, Bonaparte's Gulls nests are arboreal, usually from 5 to 15 feet up in a spruce tree! They breed in the northern boreal forest, and place their flimsy stick platforms in stunted spruce near water. I have looked into one of their abodes, once. On a trip to Churchill, Manitoba, I spotted a Bonaparte's Gull nest about ten feet up in the boughs, and clambered up for a look. The parents were rather displeased, and expressed themselves by attempting to whack me in the head like tiny feathered Stukas on a dive-bombing mission.

November is THE month for Bonaparte's Gull-watching along Lake Erie. Sometimes thousands of them congregate around favored harbors, and one can revel in the odd squeaky buzzes produced by the pack. They are highly piscivorous at this time of year, deftly dropping to the water to nab small fish. One potential prey is spotted, the gull will drop airspeed and almost stall, lifting its head somewhat and developing a hunch-necked look. That's what this one is doing.

Bingo - sushi time! The bird has adeptly snared a small minnow, likely an Emerald Shiner.

We are indeed fortunate to have Lake Erie is our northern border. This, the second smallest of the Great Lakes, is the richest biologically and supports a tremendous fauna, including these small, graceful gulls.

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1 comment:

dAwN said...

great post..I am enjoying reading and learning from your blog...
thanks..