Long-term decline and local extinction of Clethrionomys rufocanus in boreal Sweden
2006 (English)In: Landscape Ecology, ISSN 0921-2973, E-ISSN 1572-9761, Vol. 21, 1135-1150 p.Article in journal (Refereed) Published
Over the past three decades in boreal Sweden, there has been a long-term decline of cyclic sympatric voles,leading to local extinctions of the most affected species, the grey-sided vole (Clethrionomys rufocanus). Wemonitored this decline by snap-trapping on 58 permanent plots spread over 100 km2 in spring and fall from fall1971–2003. The reason for the decline is largely unknown, although a common major factor is likely to beinvolved in the decline of C. rufocanus and of the coexisting voles.However, here we deal with the reasonabilityof one complementary hypothesis, the habitat fragmentation hypothesis, which assumes that part of thedecline of C. rufocanus is caused by habitat (forest) destruction. There was considerable local variation in thedecline among the 58 1-ha sampling plots, with respect to both density and timing of the decline; however, alldeclines ended up with local extinction almost without exception. Local declines were not associated withhabitat destruction by clear-cutting within sampling-plots, as declines started about equally often before asafter clear-cutting, which suggested that habitat destruction outside sampling plots could be involved. In amultiple regression analysis, local habitat preference (LHP; expressed as a ratio of observed to expectednumber of voles trapped per habitat) together with two habitat variables in the surrounding (2.5 · 2.5 km2)landscape matrix explained56%of the variation among local cumulated densities of C. rufocanus and hence oflocal time-series.LHPwas positively correlated and explained31%of the variation, while connectivity amongclear-cuts was negatively correlated and proximity among xeric-mesic mires was positively correlated andexplained additional 16% and 9%, respectively. Even if the overall decline cannot be connected to local clearcuttingon sampling-plots, clear-cutting and hence habitat fragmentation/destruction in the surroundinglandscapes potentially influenced grey-sided vole numbers negatively.
Place, publisher, year, edition, pages
The Hague: SPB Academic Publ. , 2006. Vol. 21, 1135-1150 p.
Clear-cutting, Cycles, Density indices, Grey-sided vole, Habitat fragmentation, Landscape matrix, Local habitat preference, Multiple regression, Population dynamics, Time-series
IdentifiersURN: urn:nbn:se:umu:diva-7426DOI: 10.1007/s10980-006-7249-5OAI: oai:DiVA.org:umu-7426DiVA: diva2:147097