They seem to be raising their chicks on pigeons, mostly. Squab is tasty. I've had it several times. Best was with the breast served on top of the liver, with a great liver and sage sauce. I see a sparrow carcass there too. It's amusing to see how the chicks use their future wings as arms.
Thus far, I have seen, in their pantry, meadow vole, bunny rabbit, seagull, sparrow, and plenty of pigeons. No tofu and no vegetables at all.
Parenthood is hard work, and often boring. How loving and devoted are these parents, though? They trade off in warming and feeding the nestlings.