Sunday, 2 August 2015

Which end of what raptor?

A neighbour, by Australian standards (as her house is about 3km away in a straight line, by European standards she'd probably be in a different country) reported the following to me.
"I found a relatively tight little ball of mainly ticked hair.  It was about 8 to 10 cm long with a circumference of about 10 cm.  I opened it up to check it out and within it there were a number of bones.   ....  How about a Powerful Owl?  "
I contacted a few experts and the key points offered were:
  • The size of the item suggested it was a tad large for a Powerful Owl (hereafter, Powl) scat (based on observation of the material delivered by the Turner Powl);
  • It might be a coughed-up pellet rather than a squirted-down scat,
  • Given the location (near the Hoskinstown Plain) Wedge-tailed Eagle was a possibility.  Most raptors cough up undigestible material.
A couple of days later I was able to inspect the item.  Here are some photographs, beginning with the whole thing, reconstituted as far as possible after the initial probing.
Here is a close-up of the fur, which suggests rabbit rather than possum, but alternative views welcomed
The biggest bone pulled out was clearly a vertebra, and the lack of points of muscle attachment made me think of it being a caudal vertebra.  which argues against bunny.  See comments below.
There were a number of bone fragments of various sizes including one bit that I rate as a rib. 
We also looked briefly at a Google page for Powerful Owl scats and I decided it would be less grief if I did my own search in compiling this post.  Of course, I haven't been able to recreate the exact search results my neighbour achieved.  This was certainly one of the images (from Yowiehunters):
The discussion of that image considers it to be about twice the size of a Powerful Owl pellet.  A comment was also made that it the bone content is mostly broken, as in this case, that suggests Eagle rather than Owl.

A final thought is that Wedge-tailed Eagles are common on the Plain while Powerful Owls are far less so.

So I think I end up with this being a pellet coughed up by a Wedge-tailed Eagle rather than a scat shat by a Powl.


Harvey Perkins said...

What about a cervical vertebra - would fit with bunny better...

Flabmeister said...

Thanks Harvey. I certainly wouldn't rule that out, especially not for a baby bunny.