They do WHAT ? !!
Do you mean to say that you have pigeon-eating seagulls up there in Barcelona ? !
We have found the remains of small birds lying close to yellow-legs nests - along with fish bones and beef bones. Specifically, we have found two heads with crossed bills - although whether they actually came from Crossbills, or whether the bill got crossed during the decapitation I cannot say. (We still have the heads, buried under a tomato plant in a pot on the aft deck. We are hoping this will reduce them to the state of mere bone and beak.)
Roxanne cannot believe that her nice friendly gulls would do anything so mean and nasty - "And, anyway", she says, "they couldn't possibly fly fast enough to catch another bird."
But something is killing and decapitating those smaller birdies...
Opinions, please!