Interlinking hare and lynx dynamics using a century's worth of annual data

• Published in: Population ecology Vol. 50; no. 3; pp. 267 - 274
• Main Authors: Vik, Jon Olav, Brinch, Christian N, Boutin, Stan, Stenseth, Nils Christian
• Format: Journal Article
• Language: English
• Published: Japan Japan : Springer Japan 01.07.2008; Springer Japan; Blackwell Publishing Ltd
• Subjects: Animal populations; Behavioral Sciences; Biomedical and Life Sciences; Ecology; Evolutionary Biology; Forestry; Lepus americanus; Life Sciences; Linear model; Lynx; Lynx lynx; Normal distribution; Original Article; Plant Sciences; Population; Population cycles; Population density; Population dynamics; Predation; Predator–prey models; Questionnaires; Rabbits; Trapping; Wildcats; Zoology; Population dynamics; Population cycles; Predator–prey models; Linear model
• ISSN: 1438-3896; 1438-390X
• DOI: 10.1007/s10144-008-0088-2

The classic fur trade records on Canadian lynx (Lynx canadensis) have rarely been analysed in direct conjunction with data on its principal prey, the snowshoe hare (Lepus americanus). Comparable long-term data for hare exist only for a region south of Hudson Bay. We fitted a bivariate log-linear time-series model to this hare and lynx data to disentangle the within- and between-population interactions of these species. To reduce problems with fur returns being non-normal and non-linearly related to abundance, we transformed the fur returns to a normal distribution based on sample quantiles. The estimated effect on next year's lynx abundance of a 1% increase in current hare abundance was a 0.23% (SE = 0.05) increase in lynx. Conversely, a 1% increase in current lynx abundance corresponded to a 0.46% (SE = 0.12) decrease in next year's hare abundance. This contrasts with some earlier studies. However, these studies mixed hare data from south of Hudson Bay with lynx totals for all of Canada. Despite this asymmetry of interaction strengths, coefficients of determination were similar for hare versus lynx and lynx versus hare, because hare abundance varies more than lynx. Both species showed clear intraspecific density-dependence of about equal strength. A 1% increase in current abundance increased next year's abundance by about 0.75%.