Hello all
I think we need to be careful in assuming that orange legs and feet on
Pacific Black Ducks indicate hybridisation with Mallards. Brighter orange
legs is an indication of breeding condition in Black Ducks so we need to
consider other morphological indicators of hybridisation such as:
♂ has curled central tail feathers and variable white feathers in tail,
reduced facial stripes, warmer tones to breast feathers, the suggestion of a
pale collar (not white) and orange-yellow legs and feet. ♀ resembles an
abnormally dark ♀ mallard with orange-yellow legs and feet.
As Mike says, feral Mallards are very rare in Australia and confirmed
hybrids are almost unknown, in contrast to New Zealand where hybridisation
is of real concern.
Peter Menkhorst
-----Original Message-----
From: Mike Carter
Sent: Friday, 4 July 2014 12:30 PM
To: Nikolas Haass; Jim Tate; Kev Lobotomi; Russell Woodford;
Cc: Peter Menkhorst
Subject: Duck
A rather late entry to this debate. I have no doubt that Russell's bird was
of feral origin, a hybrid farm-yard type duck.
But the increasing occurrence of bright orange feet in otherwise 'perfect'
Pacific Black Ducks south-east of Melbourne is surprising, difficult to
explain and perhaps of some concern. Not so long ago I would count an
orange-footed bird as a Shoveler but can no longer rely on that as an ID
feature as more Black Ducks now show it. Surprising because Pacific Black
Ducks are abundant, Mallard are extremely rare and the larger free flying
farm-yard ducks very uncommon. As an illustration I took the attached shot
showing Black Duck with orange feet on one of our recent surveys on a
wetland SE of Melbourne. I realise that some individuals have brighter feet
than others but it seems to me that the brightness and frequency of orange
feet in Black Ducks is increasing.
Mike Carter
30 Canadian Bay Road
Mount Eliza VIC 3930
Tel (03) 9787 7136
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