One constant when you visit the seashore, it seems, is the presence of gulls. Whether raucously screaming or just sitting quietly, these scavengers of the sea are ever with us. At first glance, all gulls seem to be the same, apart from the difference in size between species, and the subtle varieties of leg and bill colour, eye ring, and some changes in plumage (which seems to have a standard mix of black, white and grey). Indeed, given the fact that the ‘standard’ plumage of several of the immature common gull species seems to be ‘white with brown streaks and dots’, identification at a distance can be a problem.
This is where behaviour and location come into to play. The Ring-billed Gull (Larus delawarensis) shown here at Fall River, Massachusetts, is close to a parking lot, and a café. This gull (like most others) is an omnivore, and a very opportunistic feeder; it will feed on shellfish, worms, and almost any type of refuse, if it can; it is sometimes called the ‘fast food gull’ because of its tendency to hang out near fast food outlets! The dark ‘ring’ around the beak (which is yellow) is its most note-worthy identification feature, although the attractive red outline to eye and gape is seen in close-up, along with the black upper tail coverts and black and white primaries.
Ring-billed Gulls nest in colonies and the adults return each year to the same area, often nesting within a few feet of their previous nest. They are migratory, moving to the coasts, or down the coasts in a southerly direction with the onset of winter. They are not confined to the USA, Canada, Mexico and Central America, however, as small colonies have established themselves in Ireland and Great Britain. This may be due to the fact that they can soar, as well as flap their wings to remain in flight, perhaps leading to their being carried eastward across the Atlantic Ocean on strong equinoctial gales.
Like the Black-headed Gull (Chroicocephalus ridibundus, sometimes, Larus ridibundus) in Europe, many of these gulls will never see salt water! They are quite at home on lakes and rivers, being able to exploit diverse food sources wherever they find them (there’s always a burger joint around the corner, right?) The millinery trade in the 19th century was nearly responsible for their demise in large parts of their range (their plumage was extensively used in hats of the period), but fortunately they have rebounded, and you can see many a ‘squabble’ or ‘flotilla’ of these handsome birds along many waterways. After all, you may be looking at the next Jonathan Livingston Seagull !
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