I wasn't sure how today was going to go, but it ended up that I had a few free hours in the afternoon, so I made a dash out to the Cape. I stopped at Chatham Light first, and noticed quite a few gulls feeding just inside the break.
The quick wing beat of some smaller gulls caught my eye:
They were Black-legged Kittiwakes (Rissa tridactyla)! I still haven't caught up with Black-legged Kittiwakes in California yet, so it was nice to spend some time with them in Massachusetts today.
Most of the kittiwakes were immature, with broad black stripes across their wings and dark outer primaries:
If you haven't seen kittiwakes before, note also the dark bill, dark spot (or smudge) behind the eye, and the dark collar across the hindneck.
I was curious about what the kittiwakes were feeding on. I saw two birds catch fish by surface-plunging:
I realized I didn't know very much about kittiwake prey. In Alaska, three species of fish make up the majority of their prey: Pacific Sand Lance, Capelin, and Pacific Herring. Also important are fish in the gadid (cod) family as well as lanternfishes. It turns out that much less is known about the prey of kittiwakes wintering in the western Atlantic. In fact, here's a quote from the Birds of North America Online (Hatch et al. 2009): "No information on food of wintering kittiwakes on east coast."
I'm not a fish expert, but I'm wondering if the prey in the picture above is an American Sand Lance (Ammodytes americana). It's very long and slender, and appeared to have a greenish back. If you have any thoughts about the identity of the fish, let me know!
Here's one more picture — more of seascape shot. It's hard for me to believe that it's warmer in Massachusetts than it is in Bodega Bay right now, but it sure was nice to spend a beautiful December afternoon with kittiwakes!