Subtitle:

Acta Ornithologica, vol. 34, no. 2 ; Wybiórczość względem zdobyczy u sikory modrej jako reakcja na obfitość pokarmu

Contributor:

Polska Akademia Nauk. Muzeum i Instytut Zoologii ; Meeting of the European Ornithologists' Union (2 ; 1999 ; Gdańsk)

Publisher:

Muzeum i Instytut Zoologii PAN

Place of publishing:

Warszawa

Description:

Referat wygłoszony na Second Meeting of the European Ornithologists' Union ; Bibliogr. p. 202 ; P. [199]-203 : ill. ; 27 cm ; Abstract in Polish. Taxa in Latin

Type of object:

Journal/Article

Abstract:

Some models of central place foraging relate the time taken to deliver a prey to the selectivity of the forager. If birds have to travel longer, they are expected to take only larger prey. Prey selectivity may also increase if birds have more time available for search activities. I tested this last hypothesis by experimentally increasing the food available to Blue Tits during young rearing. Insect larvae were offered to breeding adults from egg hatching to fledging of the young. Provisioning rates and prey size were studied by videotaping. In experimentally overfed broods, part of the additional food was delivered to their nestlings by the adults, while the rate of feeding with natural prey decreased compared to unmanipulated pairs. Overfed males delivered larger insect larvae than control males, while females showed no response to the treatment. Overfed males could deliver larger prey at late chick ages (when presumably the chicks' demand is higher) than controls, suggesting that control males were time- (or energy) constrained. Moreover, overfed parents appeared to choose relatively more prey that may be important in the chicks' diet. The results show that prey selectivity is related to time (or energy) budgets.

Relation:

Acta Ornithologica

Volume:

34

Issue:

2

Start page:

199

End page:

203

Detailed Resource Type:

Article

Format:

application/pdf

Resource Identifier:

oai:rcin.org.pl:45220

Source:

MiIZ PAN, call no. P.257, Vol. 34, No 2 ; MiIZ PAN, call no. P.4568, Vol. 34, No 2 ; click here to follow the link

Language:

eng ; pol

Rights:

Rights Reserved - Restricted Access

Terms of use:

Copyright-protected material. Access only on terminals at the Museum and Institute of Zoology of the Polish Academy of Sciences, may be used within the limits of statutory user freedoms.

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:

Programme Innovative Economy, 2010-2014, Priority Axis 2. R&D infrastructure ; European Union. European Regional Development Fund

Access:

Closed