These stunning little birds are always something to look for among flocks of Bonaparte’s Gulls, but picking one out of the crowd isn’t always easy! Below I’ve compiled a few photos to pour over with your favorite field guide in-hand to get geared up to find yourself a member of the worlds smallest gull species this winter.
First, a couple of Bonaparte’s gulls. As with all gulls, the first step towards making a species ID is to correctly age the bird. Grab a field guide and confirm that this is an adult Bonaparte’s.
… and this, an 1st winter Bonaparte’s…
So how do Little Gulls compare? Lets start with the youngsters. VERY dark pattern on the upperparts that, once you get a good look at it, is quite a distinct from Bonaparte’s. HEAVY black on the primaries and upperwing, giving the bird a big, black, inverted “V” on each wing. Be sure to note which feather groups are black and which aren’t, and compare to Bonaparte’s. Also note the darker crown/nape and the light (instead of distinctly black) trailing edge of the wing on the young Little Gull below (versus the young Bonnaparte’s above).
Note some of these field marks can even be seen at rest, not to mention the size difference that is often apparent.
Now, if you’ve read this far, you no doubt know that adult Little Gulls show black underwings, a very useful field mark when trying to pick them out of huge flocks of Bonaparte’s Gulls!
However, another important field mark, visible in flight and at rest, is the solid light gray upperwing with a white trailing edge and (slightly broader) white wingtip. In flight, this gives Little Gulls a very rounded-wingtip look, and at rest on the water makes the folded wingtips white, not black as in Bonaparte’s (also not the dusky/dark crown of Little Gull).
Lastly, beware of funky immature birds! Here’s a young (2nd year?) bird seen but a few feet off of shore in Ithaca, NY in April 2007. It showed dark gray, but not black underwings, a dark crown (this really is an excellent field mark to look for on candidate Little Gulls), and deceptively dark wingtips in flight and at rest (compare to adult little gulls above).
Finally, to see these birds in action, check out Jen Brumfield’s video of an adult Little Gull just off shore from Cleveland on 4 Jan 2012.