David makes a good point and let's hope his reasoning remains true. But
there have been several introduced bird species in Australia that had
restricted distributions and abundances for decades, even longer, followed
by population explosions and range expansions as a result of favourable
changes in their environment and/or improved adaptation to Australian
conditions. There is always a risk of this happening with the Mallard.
Stephen Ambrose
Ryde NSW
-----Original Message-----
From: David Clark
Sent: Sunday, 6 July 2014 6:19 PM
To: Stephen Ambrose
Cc: Greg and Val Clancy; <>
Subject: Pacific Black Duck - Mallard hybrids
Frith, in "Waterfowl in Australia", states that Mallards and Mallard hybrids
are common in city parks and gardens, some country towns and occasionally in
the wild. While Mallards haven't acclimatised to the same extent as they
have in New Zealand, Frith was concerned that the Pacific Black Duck would
cease to exist as a species and would be replaced by Mallards and hybrids.
Almost 50 years after Frith expressed those concerns, Mallards and hybrids
still seem to be restricted to cities and some country towns. Perhaps their
more sedentary nature and Australia's variable climate have combined to
prevent wider distribution.
Cheers
David
Sent from my iPad
> On 6 Jul 2014, at 5:32 pm, "Stephen Ambrose" <>
wrote:
>
> 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: Re: [Birding-Aus] 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: Re: [Birding-Aus] 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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