Fennoscandian Lesser White-fronted Goose conservation project ...

Fennoscandian Lesser White-fronted Goose conservation project – Annual report 1999
Tolvanen et al: Monitoring the autumn staging of Lesser White-fronted Geese in Kazakstan, October 1999
Table 1. The surveyed lakes and the time schedule.
Name of the lake Date of survey Co-ordinates
Kustanay region
Lake Kulykol 2–3 October 51° 20'N 61° 50'E
Lake Ayke 4–5 October 51° 05'N 61° 34'E
Lake Batpakkol 6 October 51° 25'N 62° 39'E
Lake Kulakol 7 October 51° 13'N 64° 33'E
Lake Kushmurun 8–9 October 52° 36'N 64° 28'E
Lake Koybagar 10 October 52° 35'N 65° 32'E
Lake Tyuntyugur 11 October 52° 43'N 65° 53'E
Lake Bozshakol 12 October 53° 08'N 65° 57'E
Lake Sarykol 12 October 53° 20'N 65° 32'E
Lake Tali 12–13 October 53° 16'N 64° 59'E
Kurgaldzhino–Tengiz region
Lake Sholak 2 and 13 October 50° 34'N 69° 46'E
Lakes Zhylandyshalkar, Uyalyshalkar and Zhanybekshalkar 3 October 50° 38'N 70° 27'E
Lakes Kumdykol and Ashi-Kumkol 4 October 50° 33'N 70° 46'E
Lake Kubikol 6 October 50° 53'N 68° 42'E
Lake Sochinskoye 7 October 50° 58'N 68° 12'E
Baumanskoye, Lake Korzhynkol 8 October 51° 05'N 68° 55'E
Karazhar, Lake Zultankeldi 9 October 50° 29'N 69° 33'E
Lake Saumalkol 9 October 50° 40'N 69° 43'E
Lake Shandykol 10 October 51° 04'N 69° 41'E
Lake Shunkyrkol 10 October 51° 10'N 69° 57'E
Lake Alakol 11 October 51° 15'N 69° 44'E
Burevestnik, Lake Zharlykol 11 October 51° 02'N 69° 52'E
Lake Kumkol 12 October 50° 46'N 70° 02'E
Lake Zhumai 12 October 50° 42'N 69° 48'E
Photo. Local hunting inspector of a private company holding a hunting bag
of White-fronted Geese and a Ruddy Shelduck at Lake Shandykol,
Kazakstan. © Petteri Tolvanen, October 1999
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(Tolvanen et al. 1999c). The numbers of geese on the roosting
lakes were counted early in the morning during the mass
departure from the roosting lake to the feeding grounds. The
sites of the morning counts were selected to ensure that all
flight departure sectors were covered. Data on species and age
ratios were collected during daytime in random samples of
the flocks returning back from the feeding places to the roost.
To avoid possible bias caused by different diurnal activity of
different species, samples were taken evenly during the whole
return flight period. At Lake Kulykol (in the Kustanay region)
samples were taken in different places in two consecutive days,
but at all other lakes all samples at a site were collected during
one single day.
For the lakes where adequate sample data were not
obtained, a weighted mean of the species proportion of the
sampled lakes was used to estimate the species ratio of the
lakes where we don't have sufficient data. The weighting was
made by summing up the estimates of the number of
individuals (of that particular species) from the sampled lakes,
and dividing it by the total number of geese at these lakes.
The 95% confidence intervals for the species proportions in
the sample data (Bernoulli distributed) were calculated using
the following formulas:
Lower 95% confidence limit = s-1.96 x sqrt(s x (1-s)/n)
Upper 95% confidence limit = s+1.96 x sqrt(s x (1-s)/n),
where s = mean proportion of the species in the sample data
set, n = sample size (at that particular lake) and sqrt = square
root.
3. Results
3.1. Kustanay region
The total number of geese observed was c. 247,000 individuals
(Table 2). The largest concentrations of geese were counted at
the lakes Kulykol and Ayke, while the lakes Koybagar,
Batpakkol and Tyuntyugur had moderate numbers. At the other
lakes only low numbers of geese were seen. At Lake Kulykol,
it was somewhat problematic to find a suitable point for the
morning counts: the geese had several flight directions from
the roost, and because of huge numbers of birds and intense
morning departure, some flocks could have been missed.