Kind of a squawk, but it's loud enough that a lot of people call it a roar anyway. Unless you make friends with one of them, in which case you can sometimes get it to do this really rumbly kind of almost-purr if you can convince it to let you scratch behind its ears. Mind, it takes a arseload of convincing.

Uh. Sorry, Mum.

Actually, come to think of it, I think I remember firecrabs and knarls being on the OWLs. Don't think I could turn up a firecrab on short notice, but I might be able to scrounge the knarls and hedgehogs. Shouldn't be much risk to the library, as long as you remember not to feed them.