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

Direct link
Population fluctuations and regulation in great snipe: a time-series analysis
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Population and Conservation Biology.
Show others and affiliations
2007 (English)In: Journal of Animal Ecology, ISSN 0021-8790, E-ISSN 1365-2656, Vol. 76, no 4, 740-749 p.Article in journal (Refereed) Published
Abstract [en]

1. During the last centuries, the breeding range of the great snipe Gallinago media has declined dramatically in the western part of its distribution. To examine present population dynamics in the Scandinavian mountains, we collected and analysed a 19-year time series of counts of great snipe males at leks in central Norway, 1987-2005. 2. The population showed large annual fluctuations in the number of males displaying at lek sites (range 45-90 males at the peak of the mating season), but no overall trend. 3. We detected presence of direct density-dependent mechanisms regulating this population. Inclusion of the density-dependent term in a Ricker-type model significantly improved the fit with observed data (evaluated with Parametric Bootstrap Likelihood Ratio tests and Akaike's Information Criterion for small sample size). 4. An analysis of (a number of a priori likely) environmental covariates suggests that the population dynamics were affected by conditions influencing reproduction and survival of offspring during the summer, but not by conditions influencing survival at the wintering grounds in Africa. This is in contrast to many altricial birds breeding in the northern hemisphere, and supports the idea that population dynamics of migratory nidifugous birds are more influenced by conditions during reproduction. 5. Inclusion of these external factors into our model improved the detectability of density dependence. This illustrates that allowing for external effects may increase statistical power of density dependence tests and thus be of particular importance in relatively short time series. 6. In our best model of the population dynamics, two likely density-independent offspring survival covariates explained 47·3% of the variance in great snipe numbers (predation pressure estimated by willow grouse reproductive success and food availability estimated by the amount of precipitation in June), whereas density dependence explained 35·5%. Demographic stochasticity and unidentified environmental stochasticity may account for the remaining 17·2%.

Place, publisher, year, edition, pages
2007. Vol. 76, no 4, 740-749 p.
Keyword [en]
Vertebrata, Aves, Limicolous, Population dynamics, Likelihood ratio test, Bootstrap, Covariate, Density dependence, Time series, Fluctuations, Population regulation
National Category
Biological Sciences
URN: urn:nbn:se:uu:diva-14663DOI: 10.1111/j.1365-2656.2007.01246.xISI: 000247398800013OAI: oai:DiVA.org:uu-14663DiVA: diva2:42434
Available from: 2008-01-31 Created: 2008-01-31 Last updated: 2011-02-05Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Höglund, Jacob
By organisation
Population and Conservation Biology
In the same journal
Journal of Animal Ecology
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 167 hits
ReferencesLink to record
Permanent link

Direct link