Object structure


Population studies of the grey-lag goose Anser anser breeding in the Barycz valley, Poland


Breeding of the grey-lag goose ; Badania nad populacją gęgawy Anser anser gnieżdżącej się w dolinie Baryczy, Polska


Witkowski, Józef


Polska Akademia Nauk. Instytut Zoologii


Państwowe Wydawnictwo Naukowe

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S. 179-216 : il. ; 24 cm

Subject and Keywords:

Graylag Goose ; ecology ; breeding birds ; Poland ; Barycz River Valley ; populations ; Greylag Goose ; Grey-lag Goose ; birds ; Anser anser ; Anatidae ; Aves


This study was performed during the period 1972 to 1977. The goose population numbered 280-312 pairs. A similar number was reported before World War II and then after 1960. Between these dates there occurred a sudden drop (of approx. 75%) caused by a sharp increase in the exploitation of geese by man. The population study was performed on 122-154 paire of goose breeding in one of the fish-pond complexes. The geese nested exclusively on ponds. The time of start of egg laying coincided with the disappearance of ice cover, which could be explained in terms of antipredatory behaviour. The clutch size per breeding female ranged from 2 to 10 (12?) eggs, the mean value in different seasons being 4.9 to 5.6 eggs. No relationship was noted between mean clutch size and time of commencement of the nesting period. The mean clutch size decreased from 6. 7 to 3.5 as the season passed. Almost all of the clutches with more than 10 eggs were laid by two females. 44.2 % of nests ended in a failure. The main causes were predation by the hooded crow and abandonment of nests, in similar proportions. Other causes accounted for only 0.9 %. In successful clutches the rate of hatching success was 90.4%. Mortality of the young (till fledging) was 27.4 %. The mean production of young per breeding pair in one season was 2 young. The ratio of actual to potential production was 38%. This was sufficient to ensure stability of the goose population.


Acta Ornithologica





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MiIZ PAN, call no. P.257, T. 19, Nr 8 ; MiIZ PAN, call no. P.4568, T. 19, Nr 8 ; click here to follow the link


eng ; rus ; pol


Creative Commons Attribution BY 3.0 PL license

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Copyright-protected material. [CC BY 3.0 PL] May be used within the scope specified in Creative Commons Attribution BY 3.0 PL license, full text available at: ; -

Digitizing institution:

Museum and Institute of Zoology of the Polish Academy of Sciences

Original in:

Library of the Museum and Institute of Zoology of the Polish Academy of Sciences

Projects co-financed by:

Operational Program Digital Poland, 2014-2020, Measure 2.3: Digital accessibility and usefulness of public sector information; funds from the European Regional Development Fund and national co-financing from the state budget.