uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Associating with kin affects the trade-off between energy intake and exposure to predators in a social bird species
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Population and Conservation Biology.
2007 (English)In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 74, no 3, 497-506 p.Article in journal (Refereed) Published
Abstract [en]

Individuals have to trade-off energy intake against the risk of predation when foraging. However, in group-living species, social interference will limit the range of choices for subordinate individuals. The trade-off between foraging and predation risk may be even more complex in species that associate in family groups because relatives can provide benefits to each other that are withheld from nonrelatives. As a consequence, nonrelatives may be forced to take greater risks to gain similar amounts of energy as relatives. Here, I investigate how the energy–risk trade-off varies among individuals in a social, group-living species, the Siberian jay, Perisoreus infaustus. Groups in this species consist of a breeding pair, together with retained offspring and/or nonrelated immigrants. I manipulated food quality at feeding sites that differed in their visibility to predators and observed the differences in foraging patterns between different group members. Adults and their offspring fed more often at the protected feeding site when it contained high-quality food, but switched to the more exposed site when this site offered higher quality food than the protected site. In contrast, immigrants spent a similar amount of time at each feeding site, independent of food quality. Birds generally spent more time waiting for access to the high-quality food source and protected feeding site, and family members generally harassed immigrants that tried to access these sites. None the less, all birds had a similar overall food intake, suggesting that immigrants pay substantially higher costs than other members to attain the equivalent level of energy intake.

Place, publisher, year, edition, pages
2007. Vol. 74, no 3, 497-506 p.
Keyword [en]
family, food quality, kinship, Perisoreus infaustus, Siberian jay
National Category
Biological Sciences
URN: urn:nbn:se:uu:diva-94432DOI: 10.1016/j.anbehav.2006.11.031ISI: 000250180700017OAI: oai:DiVA.org:uu-94432DiVA: diva2:168273
Available from: 2006-04-20 Created: 2006-04-20 Last updated: 2011-01-27Bibliographically approved
In thesis
1. Effects of Habitat Quality on Behavioural Decisions and Population Dynamics in the Siberian Jay
Open this publication in new window or tab >>Effects of Habitat Quality on Behavioural Decisions and Population Dynamics in the Siberian Jay
2006 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The dynamics of natural populations may be influenced by a variety of factors, ranging from feeding interference and territoriality to the risk of predation and climatic effects. The relative influence of these factors may be contingent upon the quality of the habitat in which individuals reside. A factor that can largely affect population dynamics and that often covaries with habitat structure is predation risk. However, the combined effect of habitat and predation risk can vary according to the social context and intrinsic characteristics that affect individual behavioural responses. This thesis investigates the effects of habitat quality at the level of the population and the individual, and examines how it relates to the above factors in Siberian jays (Perisoreus infaustus), a territorial, group-living species in which the main cause of mortality is predation. The results demonstrate a strong effect of habitat on survival, reproduction and behaviour. Mortality was generally higher in open areas and managed forests and reproductive success decreased after forest management. Breeding females were more sensitive to environmental factors than males, possibly because of higher reproductive costs. Estimates of spatial demography suggested that there were more sinks than sources, and that they were located in open, managed forests. Behavioural decisions confirmed that open forests were associated with higher predation risks. However, decisions depended on social context; immigrants took highest risks and were the recipients of most aggression, largely an effect of social subordination. Also, parents provide their offspring with benefits that are withheld from immigrants. As a result, first-year survival was higher in retained offspring. Investigating the effects of multi-scale habitat quality on individual behaviour and population dynamics has generated an increased understanding of the effects of forest management on the dynamics of this population. This approach should facilitate development of an effective conservation management policy for this species.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2006. 45 p.
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 174
Biology, Perisoreus infaustus, relatedness, delayed dispersal, predation risk, foraging, trade-off, demography, source-sink dynamics, forest structure, Biologi
urn:nbn:se:uu:diva-6835 (URN)91-554-6553-6 (ISBN)
Public defence
2006-05-12, Zootissalen, Evolutionary Biology Centre, Norbyvägen 9, Uppsala, 10:00 (English)
Available from: 2006-04-20 Created: 2006-04-20 Last updated: 2010-03-16Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text
By organisation
Population and Conservation Biology
In the same journal
Animal Behaviour
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 204 hits
ReferencesLink to record
Permanent link

Direct link