Cara Cara Raiding a Nest
I'm posting this, because at the time I took the picture, I though the yellow patch in the chest was due to egg yolk dropping. Judd Patterson explaind to me that it was not, but rather a pouch where they store the food and it can look like a tennis ball!!!
Caught in the act. Whose nest did he raid?
No idea, but ate almost all of the eggs, I'm guessing a turtle? We were pretty close and he didn't seem bothered. He left two eggs when he was full, anst the Crows got them:(
Nice capture Fabs.
Love the detail in the eye. and the sharpness of the beak and egg.
Well done.
Sharna
This is fascinating Fabs. I did not realise that this feature was found in other caracaras. I knew it from the Striated Caracara or "Johnny Rook" of the Falkland Islands and southern Tierra del Fuego. The image shows a golf-ball sized, orange "protuberance" at the top end of the keel of a Striated Caracara, observed at New Island, Falklands, on 21 Oct 2006.
In my experience immature and adult Striated Caracaras have the feature but in youngsters its pale coloured. In adult Striateds, the colour is that beautiful orange that you see around the facial skin. You see adults and immatures with and without the feature so this could be males and females or they may conceal it within the plumage. I'll look into it. I had not heard the idea that it is a food storage organ (crop?), but it is a fascinating possibility. Let's see what more we can find out about this feature. Do all species of caracara have it?
BTW, Striated Caracaras are one of the rarest raptors in the world but you wouldn't think so on the Falklands, where they seem to be everywhere. They are very inquisitive and tame and we would warn our passengers not to leave anything on the ground as the Johnny Rooks would investigate and fly off with smaller items. They are associated with seabird colonies on the Falklands and eat albatross and penguin eggs and chicks, and just about anything else.
John, that is one beautiful bird! I guess the pouch is common tot the species, then?
They about anything I see, here's one having a turtle. The Crows are always after left over, this time the on Crow got so annoying, the Cara flew away with her meal.
Captured through a link fence.
Beautiful images you two! How fascinating!
Great topic! Here is an image that I took of a Crested Caracara with an enlarged crop, showing the yellow skin of this species. What's even more amazing is that 5 minutes earlier this Caracara had walked up to the dead coot and had no visible crop at all...in just 5 minutes it had filled out to this point. Gotta eat while the eating is good! :)
Very nice Judd. I recently read the Birds of North America account of the Crested Caracara and it only makes passing mention of the crop causing this. I don't think much is known about the anatomy of what is going on.
I can't think of another bird species that literally advertises that it has just fed by showing a full crop to the outside world. Maybe caracaras do it to show other potential mates that they are good feeders and therefore good providers? Do we know if both sexes do this or only males? As the sexes are alike you would have to see two birds together as a pair, both showing the "bulge".
Bald eagles also have a crop but it is not usually visible. The crop also serves the function to separate substances such as bones, feathers etc. from digestible meat. They will at a later time regurgitate it much as a cat will a hair ball.
Nice image BTW.
I can't think of a bird that doesn't have a crop, but there aren't many that show them off externally like caracaras.
Owls do not have crops.Originally Posted by John Chardine
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