NZ birds are less colourful than Australian ones - why?
A guess - far fewer species so far less need to be distinctive.
In Australia we have four Petroica Robins (Scarlet, Flame, Pink, Rose)
in the east. Some of these overlap with others in habitat - therefore
bright distinctive colours may be required in territorial males.
In NZ there are only two Petroica sp - the Tomtit (yellow breast
S.Island, white in north) and the Robin - basically grey all over.
(The Chatham is Black Robin is black and a long way offshore).
I had a heated discussion with an English tourist about Mallards and
Black/Grey Ducks, while observing mongrel hybrids in Christchurch. As
she believed that ducks could not interbreed unless they were the same
species, and therefore that the local Grey Ducks had 'deteriorated' by
losing bright male colouring, she thought the introduction of Mallard to
'give them back their correct colours' was a Good Thing. When we were
in NZ we saw only 2 pair of true Grey Duck on a very isolated South
Island lake. Everything else was a Mallard/Grey hybrid.
Anthea Fleming
On 26/07/2011 1:19 PM, Tony Lawson wrote:
A friend recently posed these questions. Does anyone have a good answer?
Tony
Both were questions asked yesterday at a course I'm teaching, and I
can't satisfactorily answer either.
1. Why are NZ birds generally less brightly coloured than east coast
Australian ones?
A couple of possible responses occur to me:
a. It's a false premise - there are too few terrestrial native NZ
species to make a valid comparison.
b. NZ species tend to be dense forest dwellers, where colour is less
relevant in communication than in the open forests and woodlands of
eastern Australia. But since I haven't even set foot in our nearest
Gondwanan neighbour I'm not even sure if my starting point is correct.
In any case I don't find either response very satisfactory.
2. What is it about WA that 'fades' birds?! eg Yellow-tailed to
White-tailed Black-cockies; Eastern Yellow to Western Yellow and
White-breasted Robins.
It's such a small sample size that I'm forced to concede that it's
probably coincidence, but that doesn't satisfy me either.
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