Thanks for the replies guys, thought I must have been missing something - I've probably killed the 3 creatures like 20 times already!! but never saw the gap to get to the fourth.
I'll have to give the howling another go too. Couldn't quite get the hang of it the first time.
By the way, Super Mario 64 on Wii rocks!!

I've only ever played it at length on an emulator on my pc before, but I love being able to just load it up on the Wii. I'm looking forward to playing Zelda OOT as I've never played that before.