Publications by authors named "Kaja Johnsen"
Article Synopsis
- Small rodent populations exhibit distinct population dynamics, with the northern hemisphere experiencing regular cycles in species like voles and lemmings.
- In contrast, southern hemisphere rodents face large, irregular outbreaks rather than consistent cycles.
- The text identifies key areas of research and ten critical questions that need to be addressed to better understand these dynamics across different ecosystems.
Background: Social behaviour has been linked to hypotheses explaining multiannual population cycles of small rodents. In this paper we aimed to test empirically that the degree of space sharing among adult breeding female voles is higher during the increase phase than in the crash phase, and that the degree of sociality is positively related to population growth rate as suggested by Lambin and Krebs (Oikos 61:126-132, 1991) and Andreassen et al. (Oikos 122:507-515, 2013).
View Article and Find Full Text PDFVole population cycles are a major force driving boreal ecosystem dynamics in northwestern Eurasia. However, our understanding of the impact of winter on these cycles is increasingly uncertain, especially because climate change is affecting snow predictability, quality, and abundance. We examined the role of winter weather and snow conditions, the lack of suitable habitat structure during freeze-thaw periods, and the lack of sufficient food as potential causes for winter population crashes.
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