eBirders! Take care with identification of non-breeding Aussie Grebe & Hoary-headed Grebe

[Michael Lenz via Canberrabirds <>]

  Thanks Kim for this reminder!

One of the areas I visit regularly is West Belconnen Pond where both species occur. But I find that some of the field marks you have listed are not always easy to see, especially when the birds are not close (e.g. eye colour). Likewise, whether or not the edge of the cap runs through the eye or just below the eye, can be difficult to see. And when birds are in transition from breeding to winter plumage, the contrast from the cap to the whitish cheeks can be a bit blurred (at least to my eyes).

The characteristic that is readily picked up, even when the birds are further out, is the colouring of the flanks. In the A Grebe they have a rusty tinge, while in the HH Grebe they are grey. The ABG says for the A Grebe that the flanks are "often rusty tinged".  HANZAB  mentions no restrictions: adult non-breeding: flanks buff, juvenile: flanks warm buff.

When seen head-on, in the HH Grebe the neck is creamy white over its full length, while in the A Grebe it is greyish at the lower end.

Michael Lenz

On Sat, 4 May 2024 at 12:35, Kim Farley via Canberrabirds <> wrote:

Hi all 

As the weather cools, our local Australasian and Hoary-headed Grebes are losing the features we associate with breeding.This makes identification more difficult. There are also a fair few immature birds about and these cause identification troubles too. 

To help eBirders, and in summary, if a small grebe doesn't have the bright yellow patch of bare skin at the gape of the bill and has a grey head and neck, it doesn't mean it is a Hoary-head. It could be a non-breeding Aussie or an immature Aussie. 

And for more detail, use your binoculars to look for:

- in Australian Grebe, non-breeding and immature -- yellow eye, pale patch of bare skin at the gape of the bill and with the edge of the grey cap running through the eye. Some adults will retain a bit of chestnut on the neck and head, so look for that too.

- in Hoary-headed Grebe, non-breeding and immature -- white eye, no bare skin or patch at the gape, edge of the grey cap running just below the eye. 

For even more detail, consult a good field guide. My favourite is the Australian Bird Guide, by Menkhorst and others. It has excellent pictures of the above features and very good text as well. You could also use any of the moderated photo archives, such as the Macaulay Library or Canberra Nature Map to view photos of both species. 

Kim

ACT eBird reviewer

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