Abstract
Understanding how climate can interact with other factors in determining patterns of species abundance is a persistent challenge in ecology. Recent research has suggested that the dynamics exhibited by some populations may be a non-additive function of climate, with climate affecting population growth more strongly at high density than at low density. However, we lack methodologies to adequately explain patterns in population growth generated as a result of interactions between intrinsic factors and extrinsic climatic variation in non-linear systems. We present a novel method (the Functional Coefficient Threshold Auto-Regressive (FCTAR) method) that can identify interacting influences of climate and density on population dynamics from time-series data. We demonstrate its use on count data on the size of the Soay sheep population, which is known to exhibit dynamics generated by nonlinear and non-additive interactions between density and climate, living on Hirta in the St Kilda archipelago. The FCTAR method suggests that climate fluctuations can drive the Soay sheep population between different dynamical regimes--from stable population size through limit cycles and non-periodic fluctuations.
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- Coulson T., Catchpole E. A., Albon S. D., Morgan B. J., Pemberton J. M., Clutton-Brock T. H., Crawley M. J., Grenfell B. T. Age, sex, density, winter weather, and population crashes in Soay sheep. Science. 2001 May 25;292(5521):1528–1531. doi: 10.1126/science.292.5521.1528. [DOI] [PubMed] [Google Scholar]
- Gilpin M. E., Ayala F. J. Global models of growth and competition. Proc Natl Acad Sci U S A. 1973 Dec;70(12):3590–3593. doi: 10.1073/pnas.70.12.3590. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grenfell B. T., Price O. F., Albon S. D., Clutton-Brock T. H. Overcompensation and population cycles in an ungulate. Nature. 1992 Feb 27;355(6363):823–826. doi: 10.1038/355823a0. [DOI] [PubMed] [Google Scholar]
- Hurrell J. W. Decadal trends in the north atlantic oscillation: regional temperatures and precipitation. Science. 1995 Aug 4;269(5224):676–679. doi: 10.1126/science.269.5224.676. [DOI] [PubMed] [Google Scholar]
- Leirs H., Stenseth N. C., Nichols J. D., Hines J. E., Verhagen R., Verheyen W. Stochastic seasonality and nonlinear density-dependent factors regulate population size in an African rodent. Nature. 1997 Sep 11;389(6647):176–180. doi: 10.1038/38271. [DOI] [PubMed] [Google Scholar]
- May R. M. Biological populations obeying difference equations: stable points, stable cycles, and chaos. J Theor Biol. 1975 Jun;51(2):511–524. doi: 10.1016/0022-5193(75)90078-8. [DOI] [PubMed] [Google Scholar]
- May R. M. Biological populations with nonoverlapping generations: stable points, stable cycles, and chaos. Science. 1974 Nov 15;186(4164):645–647. doi: 10.1126/science.186.4164.645. [DOI] [PubMed] [Google Scholar]
- Mysterud A., Stenseth N. C., Yoccoz N. G., Langvatn R., Steinheim G. Nonlinear effects of large-scale climatic variability on wild and domestic herbivores. Nature. 2001 Apr 26;410(6832):1096–1099. doi: 10.1038/35074099. [DOI] [PubMed] [Google Scholar]
- doi: 10.1098/rspb.1999.0770. [DOI] [PMC free article] [Google Scholar]
- Stenseth N. C., Chan K. S., Framstad E., Tong H. Phase- and density-dependent population dynamics in Norwegian lemmings: interaction between deterministic and stochastic processes. Proc Biol Sci. 1998 Oct 22;265(1409):1957–1968. doi: 10.1098/rspb.1998.0526. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stenseth Nils Chr, Mysterud Atle, Ottersen Geir, Hurrell James W., Chan Kung-Sik, Lima Mauricio. Ecological effects of climate fluctuations. Science. 2002 Aug 23;297(5585):1292–1296. doi: 10.1126/science.1071281. [DOI] [PubMed] [Google Scholar]
- Stenseth Nils Chr, Ottersen Geir, Hurrell James W., Mysterud Atle, Lima Mauricio, Chan Kung-Sik, Yoccoz Nigel G., Adlandsvik Bjørn. Review article. Studying climate effects on ecology through the use of climate indices: the North Atlantic Oscillation, El Niño Southern Oscillation and beyond. Proc Biol Sci. 2003 Oct 22;270(1529):2087–2096. doi: 10.1098/rspb.2003.2415. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walther Gian-Reto, Post Eric, Convey Peter, Menzel Annette, Parmesan Camille, Beebee Trevor J. C., Fromentin Jean-Marc, Hoegh-Guldberg Ove, Bairlein Franz. Ecological responses to recent climate change. Nature. 2002 Mar 28;416(6879):389–395. doi: 10.1038/416389a. [DOI] [PubMed] [Google Scholar]
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