Hi Anthea
Thank you for your reply. I'm sure you're right. Birds will take advantage
of plentiful food supplies when they can. Your e-mail reminded me of an
occasion in 1989 when the Cooper Basin was completely flooded, water was
eleven metres deep over the Innamincka Causeway, lapping at the door of
the Inland Mission. One of the formed roads across a salt pan in the basin
was breeched by the flood and the waters were rushing through the gap in a
torrent sweeping anything that was in the flood waters past. A large group
of raptors were gathered on the road either side of the breech. As
something edible was swept past they simply flew out, grabbed it and
landed back on the road to consume it. It was like a Bistro.
Kind regards
Chris Shaw
Mobile: 0409 675912
W www.chc.ca <http://www.chcaustralia.com/>
"There are no shortcuts to any place worth going." Beverly Sills
On 16/05/12 10:14 AM, "brian fleming" <> wrote:
> Why do birds congregate on ephemeral wetlands?
> This is a topic which has given me a lot of thought.
>
> I believe that when a dry waterhole, billabong or creekbed - or just
>a depression in a paddock - is re-charged, either by floodwater spilling
>in from adjacent water-courses or by heavy rain, there must be a huge
>hatching of microscopic life such as waterfleas (Daphnia) and
>micro-plants from spores and eggs present in the dry mud and a
>consequent rapid increase in anything that feeds on them. Yabbies come
>up from the mud. Plus the fact that flood-waters often wash in fish-fry
>and eggs, and much other water-life, which develop rapidly in the still
>shallow water which is warmed by sunlight. Not to mention adult fish
>which are marooned when the water goes down - alas, often Carp these days.
>
> Back in 1977, I observed floodwater spreading across the Ivanhoe
>Golfcourse (Vc.)and adjacent public park at Chelsworth Park and Wilson
>Reserve. Black Ducks and Dusky Moorhens were running with the advancing
>water and each time a tussock of grass was flooded, they rushed to take
>advantage of the large numbers of insects and grass-seeds which were
>washed out of it. A Great Egret and White-faced Herons were fishing in
>the floodwaters.
>
> In summer 1975-76 (not quite sure of date) the lakes in Wyperfeld
>National Park were filled by floods from the Grampians coming down the
>Wimmera River. I heard a BOC member give an account of this at a
>meeting (unfortunately not noted in club journal). He observed the
>water as it arrived in the park and told us that it was accompanied by
>Swamphens and Moorhens which were running with the water and feeding in
>what they found washed out of leaf-litter and debris in the creek-bed.
>The water was moving at human walking pace. The distinctive calls of the
>birds alerted him to go and see what was happening - at the time there
>had been no waterbirds in the park at all.
>
> Anthea Fleming
>
>
>
>
>
>On 16/05/2012 12:54 AM, Chris Shaw wrote:
>> I've long been fascinated why birds congregate in such large numbers on
>>ephemeral ponds. On a recent bit of a ramble through northern Victoria I
>>came across another couple of places where this occurs. That and a few
>>other rumblings are on my blog:
>>
>> http://topbirdsandeveryfing.typepad.com/top-birds-everyfing/
>>
>>
>> Chris Shaw
>>
>>
>> Mobile: 0409 675912
>>
>>
>>
>>
>>
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do more and come home safely."
***Training & Competency – One of the twelve elements of CHC’s Integrated SMS***
At CHC we select the best people by matching qualifications and competencies to
the role, then maintaining that level of competency through continual training.
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