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Location of the study areas in the lowland (square) and mountain forest (circles) regions. In the lowland, landscape comparisons were based on data for the western (50 9 100 km) part of that study area

Location of the study areas in the lowland (square) and mountain forest (circles) regions. In the lowland, landscape comparisons were based on data for the western (50 9 100 km) part of that study area

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Changes in forest landscape structure have been suggested as a likely contributing factor behind the long-term decline in the numbers of cyclic grey-sided voles (Clethrionomys rufocanus) in northern Fennoscandian lowland regions in contrast to mountain regions due to the absence of forest management in the mountains. This study, for the first time,...

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... was made in one lowland region near Umeå (Vindeln), northern Sweden (& 63°50 0 N, 19°50 0 E) in 1971-2008, and three mountain regions: near Ammarnäs (& 67°30 0 N, 17°50 0 E) in -1998and 2001 (Fig. 1). The lowland region was located in the middle boreal sub-zone and the mountain regions in the alpine belts and the northern boreal sub-zone including the subalpine belt (Sjörs ...
Context 2
... of the major aims of the current study was to compare abundance of the grey-sided vole in forest habitats in the lowland and mountain regions. Data for the LF region was based on data from the western half of the LF study area (50 9 100 km) ( Fig. 1), representing twenty-nine 2.5 9 2.5 km large land- scapes (in the following abbreviated as landscape(s)) from which suitable landscape data were available. The three MF regions represented a total of 14 non- overlapping landscapes, five around Stora Sjöfallet, four around Ammarnäs and five around Vålådalen/ Ljungdalen (see below ...

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Cyclic dynamics with extensive spatial synchrony has long been regarded as character-istic of key herbivores at high latitudes. This contrasts to recent reports of fading cycles in arvicoline rodents in boreal and alpine Fennoscandia. We investigate the spatio-temporal dynamics of boreal red fox and alpine arctic fox in Sweden as a proxy for the dynamics of their main prey, voles and Norwegian lemming, respectively. We analyse data from five decades, 1960–2008, with wavelets and autocorrelation approaches. Cyclic dynamics were identified with at least one method in all populations (arctic fox n = 3, red fox n = 6). The dynamics were synchronous between populations, or coupled with a 1-yr lag, in 8 of 13 pairwise comparisons. Importantly though, the dynamics were heterogeneous in space and time. All analytical approaches identified fading cycles in the three arctic fox populations and two northern red fox populations. At least one method identified similar patterns in three southern red fox populations. Red fox dynamics were cyclic in the 1970s primarily, while arctic fox dynamics was cyclic until the late 1980s or early 1990s. When cyclic, 4-yr cycles dominated in arctic fox and northern red fox, whilst 3–4-yr cycles was found in southern red foxes. Significant cyclic regimes reappeared in the 1990s or 2000s in two red fox populations and one arctic fox population. Cycles and regionally coupled dynamics appeared associated in northern arctic and red foxes. This study supports accumulating evidence which sug-gests that cyclic and synchronous patterns in the dynamics of lemmings and voles are nonstationary in space and time. Furthermore, the similar patterns of change in both fox species indicate that persistence of cycles is governed by similar mechanisms in lemmings and voles.