Certainly the first part of John’s message is correct. The outer sheath is keratin, covering bone. In between is blood vessels, (and whatever else) that allow
things like seasonal or age related changes of the colours of the beak. You can see the space for these along the bones if you look at the bony base of the beak (after the keratin sheath has come off the bone). So of course there is some (probably variable)
sponginess. Variously long after death, the keratin sheath will simply slide off the bone. This can be averted by retaining the specimen in a clean and dry environment (e.g. museum). The bit about
in the case of bulbous beaks like the Rosella's, hollow, or filled with air pockets at the top. This is certainly true of the huge absurd bills of hornbills, toucans and
likely others. I would think not as fitting to hard beaked birds like parrots (but I have never pulled apart a parrot’s skull). The thickness of the keratin sheath will no doubt vary among bird groups. This part I don’t know but parrots and birds that eat
hard things probably have a much thicker and harder keratin layer than others. The injury on that rosella would seem most likely to have been caused
in a fight with another Crimson Rosella. Both bone and presumably keratin should be able to heal. But that is a guess.
Philip
From: calyptorhynchus . [
Sent: Friday, 15 April, 2016 7:35 AM
To: Con Boekel; Canberra Birds
Subject: Re: [canberrabirds] Crimson Rosella beak damage
My understanding is that birds' beaks are amde of keratine, the stuff human finger nails are made of, and also, in the case of bulbous beaks like the Rosella's, hollow, or filled with air pockets at the top.
In other words I think that the injury isn't going to harm the Rosella and it will heal.
The Powl that was a Botanic gardens in the late 2000s had a similar injury at the top of its beak. If we subscribe to the theory that the current Turner Powl is the same bird, then it will have healed in the
interim.
John Leonard
On 14 April 2016 at 20:15, Con Boekel <> wrote:
Attached is an image of an adult Crimson Rosella. I will attach another image to my next email. the images are of the same bird but from different angles. The damage on the left hand side of the beak matches the damage on the right hand
side of the beak. One possibility is that the bird was injured in a fight with another Crimson Rosella.
regards
Con
Crimson Rosella
14 April 2016
Campbell Park
Con Boekel
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John Leonard
Canberra
Australia
www.jleonard.net
I want to be with the 9,999 other things.
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