But I went there to see this:
In late November, I wrote about an interesting behavior — Bonaparte's Gulls pirating food from Sanderlings. I was intrigued enough by this behavior that I went back to watch some more. This time, the gulls were pirating food from Marbled Godwits.
Here's a series of shots as the gulls approached the godwits:
The gulls were fairly aggressive about it — running towards the godwits when it looked like they might have prey, vocalizing, and entering the "godwits' space." Several times I saw the godwits poke or chase the gulls away.
I'm not sure if all Bonaparte's Gulls do this, or if some individuals decide it's a productive way to obtain food. Later I checked Salmon Creek itself, and there were at least 30 Bonaparte's Gulls feeding along the shoreline there, without exhibiting pirating behavior. Or do individuals alternate between feeding strategies?
By the way, because there are so many Bonaparte's Gulls there right now (near the mouth of the Creek), and for some reason they're quite vocal, it's a great opportunity to listen to them and to learn their calls (perhaps I'll try to record them).
A few hundred Heermanns gulls settle on Stinson Beach & though most forage for mole crabs on their own (running after retreating waves and then back again like sanderlings), each group of feeding godwits often includes one or sometimes two of the gulls who will run towards a godwit with something in its mouth, startling it & then picking up a prize if dropped. It looks like they're taking advantage of the godwits' longer bills and ability for deeper probing. Haven't noticed any of the 4 or 5 other species of gulls living there doing this.
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