Even if significant contamination of the Pacific Black Duck (PCB) gene pool
through hybridisation with the Mallard does or does not occur, if the
Mallard substantially increases its Australian range and/or abundance, it
could still impact significantly on PCBs through competition for resources.
Braithwaite & Miller (1975) raised that concern in relation to prolonged
droughts when the number and size of wetlands are reduced and competition
between the two species potentially increased.
Braithwaite, L.W. & Miller, B. (1975). The mallard, Anas platyrhynchos, and
mallard-black duck, Anas superciliosa rogersi, hybridization. Australian
Wildlife Research 2: 47-61.
Stephen Ambrose
Ryde NSW
-----Original Message-----
From: Birding-Aus On Behalf Of
Greg and Val Clancy
Sent: Sunday, 6 July 2014 10:24 AM
To: Graeme Stevens; Kev Lobotomi; Peter Menkhorst; Mike Carter; 'Nikolas
Haass'; 'Jim Tate'; 'Russell Woodford';
Subject: Pacific Black Duck - Mallard hybrids
During the late 1970s or early 1980s a officer form the Conservation
Department (not sure of name), based in Wellington New Zealand, visited
Australia and I met him in Grafton. He was here to warn us Aussies of the
impending threat posed by the introduced Mallard based on the New Zealand
experience, which has been disastrous. I was very concerned as I had
observed hybrids in Sydney and had observed Mallards associating with Black
Ducks in the Grafton area. I have a from a desk calendar on my office
which reads "The best way to solve problems is not to create them" so I
thought that it would be best to nip the Mallards in the bud. I wrote to
the National Parks & Wildlife Service alerting them to the issue. The
response from a senior researcher who had carried out research on waterfowl
for many years was that as the gene pool of the Pacific Black Duck in
Australia was very large the chances of significant disruption from a small
number of Mallard genes was very unlikely. So in her opinion there was no
problem. I disagreed with her but without any co-ordinated effort at that
time Mallard hybrids have increased. It seems to be a human foible that we
don't want to do anything about a problem until it is so large that we can't
effectively do anything anyway and then then we throw millions of dollars
at the problem with little or no effect.
Regards
Greg
Dr Greg. P. Clancy
Ecologist and Birding-wildlife Guide
| PO Box 63 Coutts Crossing NSW 2460
| 02 6649 3153 | 0429 601 960
http://www.gregclancyecologistguide.com
http://gregswildliferamblings.blogspot.com.au/
-----Original Message-----
From: Graeme Stevens
Sent: Saturday, July 05, 2014 3:21 PM
To: Kev Lobotomi ; Peter Menkhorst ; Mike Carter ; 'Nikolas Haass' ; 'Jim
Tate' ; 'Russell Woodford' ;
Subject: Pacific Black Duck - Mallard hybrids
Just a small addition to this discussion - particularly the record Nikolas
contributed:
I have undertaken close to 50 Atlas surveys at Warriewood (Sydney Northern
Beaches NSW) in recent years and while pure Mallards are occasionally on the
Warriewood Wetlands reserve and the settlement ponds, they seem to be much
more common and resident along Mullet Creek between the Wetlands and
Narrabeen Lagoon. These appear to be pure Mallards, generally paired.
There are of course plenty of Pacific Blacks on both the Wetlands and the
Creek so the opportunities for an enthusiastic Mallard Drake are plentiful!
I have certainly recorded what I considered to be good hybrids. Mind you
there are other mixed feral hybrids occasionally which could confuse the
issue (Muscovy, Chinese Whites, Khaki Campbell etc). They could certainly do
with a clean out.
Best to all
Graeme Stevens
> From:
> To: ; ; ;
> ; ;
> Date: Sat, 5 Jul 2014 00:10:45 +1000
> Subject: Re: [Birding-Aus] Pacific Black Duck - Mallard hybrids
>
> 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
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