Do rooks have a crop or pouch in which the bird stores food? I've seen a number Rooks from time to time with large lower bills and had always thought that the protrusion was part of a solid bill, perhaps due to age. A friend has suggested that this may be a pouch or crop. The photo below shows two different birds, with two equally different bills. The bird with the ‘normal’ bill does appear to show a fleshy part above the chin at the base of the bill. Any information regarding this would be much appreciated.
Paul
My bird photos HERE
Hi Paul, I'm no expert on Corvids but do see a lot of them in the garden and have had Rooks on rare occasions. I think you your rook on the left just has a part full crop (as like other Corvids they cache food) and the pouch under the bill is just like an expandable soft bag ! One day I counted 21 peanuts which were collected in one visit by a Jay and when I think they are the smallest corvid, I am wondering how many the Rook can collect in one sitting !
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Regards, Hazel
What you're seeing on the Rook is its gular skin, where the lower mandible attaches to the neck. Several species of birds have stretchy skin here that can be used as a storage pouch, taken to its extreme in pelicans! The crop is different - it's the first bit of the digestive tract after the oesophagus, and it's not usually obvious when a bird has food in its crop except in featherless baby birds, and in species like raptors, which scoff lots of food in one sitting and then develop a bit of a bulgy upper breast, like this: http://farm6.staticflickr.com/5468/9110614757_fac469047c.jpg
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Thanks both, the information is very much appreciated. :-)
That gular pouch is seriously impressive - no songbird visiting our garden can carry away more food than the rook.
Our herring gulls are red listed birds. Think about that the next time you hear some flaming idiot calling for a cull of them.
I’ve seen Rooks arriving in the garden with the gular skin swollen, and I’ve also seen them leaving the garden on many occasions with beaks stuffed full of food, but with no sign of the swollen part. It’s always good to learn something new.
Who’s a greedy boy then? :-)
Aha I always thought the rooks with pouch were males and the rooks with no pouch were females I did not know it was fleshy I thought it looked like a hard tough beak like a comb on a rooster or a long chest pouch like the nale african storks