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walterma 15/01/2011 17:21

Greater Scaup?

Please help, #1 & #2 Greater Scaup and #3 Tufted Duck?
NSW, 8-Jan-11

EricB 15/01/2011 20:54

Aythya ducks send shudders down my spine. Hybridization is common and problematic. If you think there is something strange about its ’jizz’ or proportions you might well be dealing with a hybrid.

Having said that the top two pics scream out Tufted. Nothing else should have a hint of a tuft! Which is responsible for the bump on the back of the top two images.

The third pic doesn’t clearly show a tuft, but its probably the angle. As long as it doesn’t have white under the tail coverts, it too is a Tuftie.

The Scaup like faces of many Tufteds are always problematic and should be treated with caution.

Here are some useful features:

1.Typically Scaup have more white extending right around the bill (including over the culmen area – rare in Tufties) – there is  a suggestion in the top 2 photos that the area over the base of the culmen is dark.

2. The white patch at the base of the bill is typically sharply demarcated in Scaup.

3. In ‘classic’ Scaup the white is typically purer white.

4.Photo number 2 highlights the greater contrast between the dark upperparts and lighter flanks in Tufted. The contrast is less in Scaup , mainly because the upperparts are a lighter shade of brown.

eRic

[[i] Last edited by RUWright at 16/01/2011 07:24 [/i]]
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