Common dynamic structure of Canada lynx populations within three climatic regions

Science

Volumn 285, Issue 5430, 1999, Pages 1071-1073

  Stenseth, Nils Chr ^a,b   Chan, Kung Sik ^c   Tong, Howell ^d,e   Boonstra, Rudy ^a,f   Boutin, Stan ^g   Krebs, Chartes J ^a,h   Post, Eric ^b   O'Donoghue, Mark ^h,i   Yoccoz, Nigel G ^a,j   Forchhammer, Mads C ^k,l   Hurrell, James W ^m  

^a Det Norske Videnskaps Akademi   (Norway)

^b UNIVERSITY OF OSLO   (Norway)

^c UNIVERSITY OF IOWA   (United States)

^d LONDON SCHOOL OF ECONOMICS   (United Kingdom)

^e UNIVERSITY OF HONG KONG   (Hong Kong)

^f UNIVERSITY OF TORONTO   (Canada)

^g UNIVERSITY OF ALBERTA   (Canada)

^h UNIVERSITY OF BRITISH COLUMBIA   (Canada)

ⁱ Fish and Wildlife Branch   (Canada)

^j NORWEGIAN INSTITUTE FOR NATURE RESEARCH   (Norway)

^k UNIVERSITY OF CAMBRIDGE   (United Kingdom)

^l Natl Environ Research Institute   (Denmark)

^m NATIONAL CENTER FOR ATMOSPHERIC RESEARCH   (United States)

more..

Author keywords

[No Author keywords available]

Indexed keywords

CLIMATE EFFECT; FELID; POPULATION CYCLE; POPULATION DYNAMICS;

ARTICLE; CANADA; CLIMATE; ECOLOGY; FOREST; INSECT; NONHUMAN; POPULATION DENSITY; POPULATION DYNAMICS; PRIORITY JOURNAL;

CANADA;

CARNIVORA; FELIDAE; INSECTA; LYNX; LYNX CANADENSIS; LYNX LYNX;

EID: 0033551915     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.285.5430.1071     Document Type: Article

References (34)

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27. Using the tests described in (22) and adopting a 5% significance level, we cannot reject the hypothesis of common slopes and the hypothesis of the common ratio of intercepts for the pairs (L1 and L2) and (L4 and L5). For L6 and L7, we cannot reject the hypothesis of common slopes in the upper regimes and that the lag-2 coefficients may be the same for the two series. However, L6 and L7 appear to have a different lag-1 coefficient in the lower regime. Thus, the evidence of common dynamics for L6 and L7 is somewhat weak. For details, see (6).
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30. We have investigated the constraint structure further (Table 1): assuming only a common structure in the lag-1 and lag-2 in the upper regime provides worse fit This suggests that the additional constraints [found by testing (6)] are significant Relocating 13 to the Pacific-maritime group yields an AIC slightly larger than -1819.38. This implies some fuzziness in the boundary of the three zones. One can classify L3 into the Pacific-maritime zone or the Continental zone. The case of Yukon seems rather clear cut: including it in the Pacific zone substantially increases the AIC and hence provides a poorer description.
31. Supplementary information is available at www. sciencemag.org/feature/data/1037845.shl.
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34. This work was initiated while several of the authors were at the Centre for Advanced Study at the Norwegian Academy for Sciences and Letters, Oslo. N.C.S. acknowledges generous support from the Norwegian Science Council and the University of Oslo. K-S.C. acknowledges generous support from the University of Iowa. H.T. acknowledges the Engineering and Physical Sciences Research Council (UK) and the University of Hong Kong for support N.C.S. and H.T. acknowledge support from UK Biotechnology and Biological Sciences Research Council/Engineering and Physical Sciences Research Council (UK) grant 96/MM109785. R.B., S.B., and C.J.K. acknowledge support from the Natural Sciences and Engineering Research Council of Canada. E.P. acknowledges the National Science Foundation (grant DBI-93-04178) for support. M.C.F. acknowledges the Danish National Research Council for support We thank A. Kenney for preparing the figure and three anonymous reviewers for providing valuable comments, helping us to clarify our argument.