Hi all!
Although Mallards fortunately aren't that common in Australia, we can't be too
complacent about there presence. One thing I have noticed is that many Mallards
that I see on ornamental ponds are males (so definitely not a population!), but
since they are males they tend to get randy & if they have nothing but black
ducks to chase I am sure they would go after them. So the chance of hybrids is
quite high! All efforts should be made to remove these birds, so they don't
pollute the native ducks with their genes!-Kevin Bartram
> From:
> To: ; ; ;
> ; ;
> Subject: RE: [Birding-Aus] Pacific Black Duck - Mallard hybrids
> Date: Fri, 4 Jul 2014 13:03:34 +1000
>
> 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: Re: [Birding-Aus] 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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