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Greetings. eBirders will have noticed the significant changes that have occurred in recent weeks to both the eBird app and the eBird web browser interface.
Among the changes is flagging rarities differently from before. Along with that has come some changes to the statuses of some species. I particularly noticed the changes to the Mallard group. The four taxa--Mallard, Northern Mallard, Mallard (domestic
type) and the Mallard-Pacific Black Duck hybrid--were, previously, all treated alike: no supporting evidence required for an eBird checklist. Following the recent updates, that remains the case for the domestic type and the hybrid, but for reports from COG's
area of interest supporting evidence is required for any report of 'Mallard'. That taxon is flagged as a rarity. 'Northern Mallard' is no longer an option.
This brings the eBird approach into line with COG's
Annotated Checklist of the Birds of the ACT: the Checklist does not include Mallard or Northern Mallard, based on expert advice that these taxa have not yet been confirmed as being in our area. The Mallard-like birds in COG's area are considered to have
some domestic duck characteristics, along with the original exotic Mallard characteristics.
Some list members may find the information below, posted by the Qld eBird reviewer Dez Wells a couple of years ago, helpful in separating the taxa in the Mallard group. I post this for information; I do not have the ornithological expertise to comment
on its accuracy or comprehensiveness.
David
Dez Wells wrote:
Queensland is currently reviewing a large number of bird species, Mallard is one of these. All individuals who have listed option 1 below have been asked to review their sighting. Individuals have been asked to provide notes on why they believe the bird is
pure form and not domesticated or if in fact domesticated to change their sighting to option 2. The review is our attempt to make the data provided by eBird in Queensland more accurate. A goal I believe all bird watchers strive to provide.
Interestingly, of all the requests made so far and replied to by bird watchers 90% have confirmed that in fact the bird in question was domesticated and that they did not realise that they had the three options to choose from or that they did not understand
the difference between the options.
Yes, we can select three options in Australia for Mallards:
Option 1:“Anas platyrhynchos - Mallard”;
Option 2: “Anas platyrhynchos (Domestic type) - Mallard (Domestic type)” and;
Option 3: The hybrid between Mallard and Pacific Black Duck – “Anas platyrhynchos x superciliosa - Mallard x Pacific Black Duck (hybrid)”.
If you select the first option, then it must show normal wild-type mallard size and wild-type phenotype. If so then use the standard “Anas platyrhynchos (Mallard)” designation. You will however need to provide a field notes/explanation and/or photo as
to why you believe this to be a wild-type bird and not a domesticated bird.
If you are unsure or have no notes for explanation then always use the second option - Anas platyrhynchos (Domestic type).
If you can identify that it is a hybrid between the Pacific Black Duck and the Mallard then use the third option - Anas platyrhynchos x superciliosa .
New Zealand eBird odes provide its members with a useful little key with ducks you suspect may be Pacific Black Ducks (Grey Ducks over there) to see if they really are pure. I have modified the table below replacing Grey Duck with Pacific Black Duck so
that bird watchers may use for this purpose in Australia.
Using the key below if your duck scores more than seven (7) it is almost certainly a hybrid Pacific Black Duck. You could put the hybrid index score in the comments column for your observation notes.
You can also use this key to look at the opposite whether the Mallard you are viewing is a hybrid or domesticated individual.
The index gives a score of 0 for the purest Pacific Black Duck and 35 for the purest Mallard.
If you select the first option, then it must show normal wild-type mallard size and wildtype phenotype. If so then use the standard “Anas platyrhynchos (Mallard)” designation. You will however need to provide a field notes/explanation and/or photo as to
why you believe this to be a wildtype bird and not a domesticated bird.
Facial stripes
Pacific Black Duck: Two clear black stripes on a cream background - 0-1
Hybrid: Obscured face stripes - 2-3
Mallard: No face stripe to a thin black eye stripe in the female - 4-5
Speculum border – anterior
Pacific Black Duck No white bar 0-1
Hybrid Thin white bar (2 mm) 2-3
Mallard Broad white bar (5 mm) 4-5
Speculum border – posterior
Pacific Black Duck Faint white line 0-1
Hybrid Thin white bar (2 mm) 2-3
Mallard Broad white bar (5 mm) 4-5
Bill
Pacific Black Duck Slate grey 0-1
Hybrid Grey-yellow 2-3
Mallard Yellow-orange 4-5
Nape
Pacific Black Duck Cream 0-1
Hybrid Creamy brown 2-3
Mallard Dark brown in female or eclipse male, varying from a dark green to a purple-green in the breeding plumage male 4-5
Tail
Pacific Black Duck Slate Grey 0-1
Hybrid Grey-brown 2-3
Mallard Creamy brown in female or eclipse male, varying from a dark green to a purple-green in the breeding male 4-5
Leg
Pacific Black Duck Grey-brown 0-1
Hybrid Grey-yellow 2-3
Mallard Yellow-orange 4-5
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