Correction about the breeding: It's herdsman lake that has a fair few pairs
though they breeding on Lake Monger as well.
> From:
> Date: Thu, 13 Sep 2012 11:02:36 +1000
> To:
> Subject: [Birding-Aus] Great Crested Grebe: Far South Coast of NSW +
> observations and questions
>
> One the previous two days I spotted a Great Crested Grebe in breeding
> plumage on Wallaga Lake in Beauty Point. What a fantastic bird! This
> location is on the northern border of the Bega Valley Shire just south
> of the Eurobodalla shire. (The border is in the lake, I believe.) By
> road, Beauty Point is about 8km north of Bermagui.
>
> For historical reasons, sightings from this spot are of interest to
> the record keepers in both shires so I sent the info along. It sounds
> like this species hasn't been spotted in the Bega Valley Shire since
> 2007 or in the Eurobodalla Shire since 2008. Based on a suggestion,
> I'm posting a note here on Birding-Aus.
>
> I didn't manage to find the bird again today but it's overcast, windy
> and cold at the moment. The lake is large and complicated and there's
> plenty of other good habitat nearby. Hopefully, I'll reacquire it and
> can post again, if people are interested.
>
> When my wife and I first spotted the bird we were pretty surprised -
> we couldn't even remember seeing one in Australia before (I checked my
> notes and we've seen them here - but not in NSW or the ACT.) Is there
> anywhere in Australia that these birds can be seen reliably?
>
> I was impressed by how long these birds can stay under water - I
> didn't remember that detail. The bird disappears with virtually no
> trace and seems to be able to stay down for a minute or more, although
> I didn't time it.
>
> I'm curious about this species preferred habitats in Australia. I've
> seen grebe species around the world in fresh, brackish, and sea water
> - but I though of Great Crested Grebes as preferring fresher water. It
> seems that I'm wrong about this - but I want to include an observation
> about Wallaga Lake. For those that don't know the area, this is a
> tidally flushed lake so its exact composition and salinity changes a
> lot over time. It was blocked more often than not (extensive silting
> from decades of logging in the hills feeding the streams flowing into
> the lake) but the entrance to the sea has been open for about two
> years without interruption. The lake normally hosts good numbers of
> Black Swans (hundreds), three kinds of cormorants, spoonbills, Silver
> Gulls, Pied Oystercatchers, pelicans, and a range of other likely
> candidates in lesser numbers (Red-capped and Hooded Plovers, Little
> Terns, Caspian Terns, any other wader that passed through, etc.) Until
> this year I had never seen any kind of grebe species on the lake. Not
> once in the better part of 10 years - although I can easily find
> Australasian Grebes in fresh water nearby. Starting about a month ago,
> around two dozen Hoary-headed Grebes showed up. Neighbors have been
> stopping to ask me about "those little ducks". I suspect that the
> water composition has changed in some way (salinity? oxygen? algae?)
> to make it attractive to these species.
>
> Here's a slimmed down excerpt from the Bird Life fact sheet on the
> Great Crested Grebe (link further below):
>
> The species breeds on fresh or brackish waters with abundant emergent
> and submerged vegetation, showing a preference for non-acidic
> eutrophic [I think that this means "nutrient rich and oxygen poor"]
> waterbodies with flat or sloping banks and muddy or sandy substrates,
> usually 0.5-5 m deep and with large areas of open water. Suitable
> habitats include small pools or lakes, backwaters of slow-flowing
> rivers and artificial waterbodies (e.g. reservoirs, fish-ponds, gravel
> pits and ornamental lakes). In Australia the species also utilizes
> swamps, reservoirs, lagoons, salt-fields, estuaries and bays, and in
> tropical Africa and New Zealand it may breed on montane, subalpine and
> alpine lakes up to 3,000 m.
>
> While on the subject, below are some references for this bird - better
> details gratefully received.
>
> I noticed some posts about Great Crested Grebes recently on the
> Canberra birding list, including a link to the Canberra Ornithological
> Group's atlas data:
>
> A visual summary of the data on the COG database for Great Crested Grebe.
> https://docs.google.com/open?id=0B7cBqe3MzqSXZjJEaVI4YjlBV0k
>
> Two were spotted on Lake Tuggeranong on the 10th.
>
> Can anyone offer some background on the Great Crested Grebe population
> in Australia? I've had a look at the new atlas but it doesn't really
> clarify things for me. From a bit of Googling, am I correct in
> gathering that there are three (largely) non-overlapping supspecies
> globally? One in Europe and North Asia cristatus), one in Africa
> (infuscatus), and one here and in New Zealand (australis). That would
> explain the huge bands of territory between here and Asia that the
> bird doesn't reside in.
>
> Bird Life Fact Sheet
> http://www.birdlife.org/datazone/speciesfactsheet.php?id=3639
>
> Geographic differentiation in the Australasian great crested grebe
> Spoiler: They don't think that the NZ population is genetically
> distinct from the Australian population.
> http://www.doc.govt.nz/upload/documents/science-and-technical/DSIS34.pdf
>
> A nice summary page with a few photos:
> http://travelling-australia.info/InfsheetsP/Podiceps_cristatus.html
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