For the interest of BIRDING-AUS, I am forwarding the following message sent
to WADERS-L. If anybody would like to become involved in VWSG fieldwork, I
can put you in touch.
Cheers, Hugo.
>Delivered-To:
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>From: Pat and Clive Minton <>
>To:
>Subject: [WADERS-L:326] Breeding Success in Arctic, 1997
>X-Listprocessor-Version: 6.0c -- ListProcessor by Anastasios Kotsikonas
>X-Comment: Waders discussion group
>Date: Sat, 10 Jan 1998 08:47:38 +0200
>
> BREEDING SUCCESS IN 1997 in EASTERN SIBERIAN ARCTIC
>
>Each Austral summer the Victorian Wader Study Group attempts to obtain a
>measure of the previous arctic breeding season's success by measuring the
>proportion of juveniles in wader populations.
>To minimise the effects of other variables samples are obtained in a
>standardised way. For the 'small waders' this involves 4 different sites,
>capture by cannon netting, and only captures in the December/February
>period. 'Twinkling' (disturbing birds to get them into the catching area)
>is also kept to a minimum as this has been found to bias the sample
>(increased % of juveniles) on occasions.
>
>The table below gives the initial results for the 1997-98 Austral summer.
>
> THE PERCENTAGE OF JUVENILE BIRDS IN WADERS CAUGHT IN VICTORIA,
> AUSTRALIA IN DECEMBER 1997/EARLY JANUARY 1998
>
> WerribeeSF Queenscliff NE W'nportBay Inverloch TOTAL
>
>Rednecked
>Stint 7.5%(617) 3.5%(862) 9%(1040) 8.5%(624) 7.2%(3143)
>Curlew
>Sandpiper 42%(132) 4.5%(70) 21%(319) -(1) 24%(521)
>Sharptailed
>Sandpiper 26%(117) 10%(20) 6%(128) -(1) 15%(265)
>
>Sample sizes (ie. catches) are given in brackets.
>
>Based on similar data obtained in each of the past 19 Austral summers
>breeding success in the Arctic in 1997 would be classed as:-
>
>Rednecked Stint poor to moderate
>Curlew Sandpiper moderate to good
>Sharptailed Sandpiper moderate
>
>In arriving at these tentative classifications account has been taken of
>the fact that one of the five catches which make up the Werribee Sewerage
>Farm total -with 116 of the Curlew Sandpipers and 80 of the Sharptailed
>Sandpipers - took place after significant twinkling on an ebbing tide with
>many birds being seen to leave the roost for the emerging tidal flats. It
>is possible(indeed probable) that this catch was biased in favour of
>juveniles. A further 'non-twinkled' catch of these species at that location
>will be attempted in the next few weeks.
>All other samples are considered to be representative of the population as
>a whole (or at least those roosting at the main locations). In that context
>it is not clear why the perecentage of juvenile Curlew Sandpipers in the
>Queenscliff sample was much lower than in Westernport Bay.
>On the basis of this information 1997 was not a 'good' breeding season in
>the eastern Siberian arctic as predicted in the 'three year,
>predator/lemming related cycle'. This is in agreement with information
>emanating from other sources (especially Pavel Tomkovich) suggesting that
>1997 was at best 'patchy'. It seems that the strict three year cycle may at
>last have been broken after a run of almost 20 years. It will be especially
>interesting and important to see what 1998 produces.
>It is hoped to obtain data on two further species - Sanderling and Ruddy
>Turnstone - in the next two weeks, and possibly on some of the medium/large
>waders in February. Any further data will be circulated via Waders-l.
>Clive Minton, Roz Jessop, Mark Barter
>on behalf of the Victorian Wader Study Group
>
>
>
>
Hugo Phillipps,
Birds Australia Conservation & Liaison,
Australian Bird Research Centre,
415 Riversdale Road,
Hawthorn East, VIC 3123, Australia.
Tel: (03) 9882 2622. Fax: (03) 9882 2677.
O/s: +61 3 9882 2622. Fax: +61 3 9882 2677.
Email: <>
Web Homepage: http://www.vicnet.net.au/~birdsaus
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