Sunday, January 7, 2018

Booboo prompts more questions of identity

Big booboo last post - since mostly corrected, but clue left as challenge. Error came from initial assumption of bird's identity. Mistake then blocked any chance of self-correction. Here's a look at recent examples of ID problems, all from within limited confines of Townsville Common Conservation Park, starting with one of most frequent, Collared Sparrowhawk (juvenile above and below: but barred adults also look alike ) versus Brown Goshawk.

Sparrowhawks stare, Goshawks glower. Easy! Except Sparrowhawks often glower a bit. And their tails (square tipped with notch, against rounded unnotched) fold inconclusively in the field. And their very long middle toes and thin legs look less impressively different in the field than in the field guides. Ditto colour, head, bill, and, specially in the north, size differences. So, no surprise if Collared Sparrowhawk ID should be challenged.

Less contentious, though commonly mislisted as Grey Shrike-thrush, Little Shrike-thrush. (above and below), previously called Rufous Shrike-thrush. Above image closely matches what birders expect to see.

Same bird taken a day earlier in less sunlight shows why Little becomes identified as Grey, which is larger, lighter grey, sounds different, and in North Queensland prefers higher and drier inland woodland.

No question about Australasian Pipit. Until it's identified as Anthus australis  australis. Because across the Top (of Australia) there's another subspecies, Anthus australis rogersi, which stands very upright, is more heavily streaked down the breast, is said to have a shorter tail and longer legs than the three other Pipit ssp.

It seems rogersi may have snuck southeast hundreds of kilometres down the NQ coast without drawing field guide attention to itself. Problems: every Pipit locally stands very upright, but often without extra heavy streaking. Tail and leg lengths difficult to measure without bird in hand.

Here's to further challenges (and fewer booboos) in 2018.


mick said...

Uh-oh! so did I give my pipit in the last post the wrong name?? The more I know about these bush birds the less I like them! They are
VERY confusing!! Your photos are always great!

Tyto Tony said...

Hi Mick,

Not only did you get it right, if anything your heavily speckled bird could mean ssp rogersi has got far, far further southeast than anyone suspected. But it really needs serious birds-in-hand studies.

mick said...

Thanks for the extra info, Tony,

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