Theoretical studies have shown that variation in density regulation strongly influences population dynamics1, yet our understanding of factors influencing the strength of density dependence in natural populations still is limited2. Consequently, few general hypotheses have been advanced to explain the large differences between species in the magnitude of population fluctuations3,4,5,6. One reason for this is that the detection of density regulation in population time series is complicated by time lags induced by the life history of species7,8 that make it difficult to separate the relative contributions of intrinsic and extrinsic factors to the population dynamics. Here we use population time series for 23 bird species to estimate parameters of a stochastic density-dependent age-structured model. We show that both the strength of total density dependence in the life history and the magnitude of environmental stochasticity, including transient fluctuations in age structure, increase with generation time. These results indicate that the relationships between demographic and life-history traits in birds9,10 translate into distinct population dynamical patterns that are apparent only on a scale of generations.
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May, R. M. Simple mathematical models with very complicated dynamics. Nature 261, 459–467 (1976)
Sibly, R. & Hone, J. in Wildlife Population Growth Rates (eds Sibly, R. M., Hone, J. & Clutton-Brock, T. H.) 11–40 (Cambridge Univ. Press, Cambridge, 2003)
Pimm, S. L. The Balance of Nature? (Univ. of Chicago Press, Chicago, 1991)
Ariño, A. & Pimm, S. L. On the nature of population extremes. Evol. Ecol. 9, 429–443 (1995)
Lande, R., Engen, S. & Sæther, B.-E. Stochastic Population Dynamics in Ecology and Conservation (Oxford Univ. Press, Oxford, 2003)
Hanski, I. Density dependence, regulation and variability in natural populations. Phil. Trans. R. Soc. Lond. B 330, 141–150 (1990)
May, R. M. Stability and Complexity in Model Ecosystems (Princeton Univ. Press, Princeton, New Jersey, 1973)
Nisbet, R. M. in Structured Population Models in Marine, Terrestrial, and Freshwater Systems (eds Tuljapurkar, S. & Caswell, H.) 89–118 (Chapman & Hall, New York, 1997)
Charnov, E. L. A note on dimensionless life-histories for birds versus mammals. Evol. Ecol. 9, 288–291 (1995)
Charnov, E. L. Evolution of life-history variation among species of altricial birds. Evol. Ecol. Res. 2, 365–373 (2000)
Royama, T. Analytical Population Dynamics (Chapman & Hall, London, 1992)
Zeng, Z., Nowierski, R. M., Taper, M. L., Dennis, B. & Kemp, W. P. Complex population dynamics in the real world: modeling the influence of time-varying parameters and time lags. Ecology 79, 2193–2209 (1998)
Bulmer, M. G. The statistical analysis of density dependence. Biometrics 31, 901–911 (1975)
Coulson, T. et al. Age, sex, density, winter weather, and population crashes in Soay sheep. Science 292, 1528–1531 (2001)
de Kroon, H., Plaisier, A., van Groenendael, J. & Caswell, H. Elasticity: the relative contribution of demographic parameters to population growth rate. Ecology 67, 1427–1431 (1986)
Lande, R. et al. Estimating density dependence from population time series using demographic theory and life-history data. Am. Nat. 159, 321–332 (2002)
Newton, I. Population Limitation in Birds (Academic, San Diego, 1998)
Lande, R. in Population viability analysis (eds Beissinger, S. & McCullough, D. R.) 18–40 (Univ. of Chicago Press, Chicago, 2002)
Sæther, B.-E. & Bakke, Ø. Avian life history variation and contribution of demographic traits to the population growth rate. Ecology 81, 642–653 (2000)
Bennett, P. M. & Owens, I. P. F. Evolutionary Ecology of Birds (Oxford Univ. Press, Oxford, 2002)
Holyoak, M. & Baillie, S. R. Factors influencing detection of density dependence in British birds. II. Longevity and population variability. Oecologia 108, 54–63 (1996)
Sæther, B.-E. et al. Life-history variation predicts the effects of demographic stochasticity on avian population dynamics. Am. Nat. 164, 793–802 (2004)
Croxall, J. P. & Rothery, P. in Bird Population Studies. Relevance to Conservation and Management (eds Perrins, C. M., Lebreton, J.-D. & Hirons, G. J. M.) 272–296 (Oxford Univ. Press, Oxford, 1991)
Sæther, B.-E., Sutherland, W. J. & Engen, S. Climate influences on avian population dynamics. Adv. Ecol. Res. 35, 185–209 (2004)
Barbraud, C. & Weimerskirch, H. Climate and density shape population dynamics of a marine top predator. Proc. R. Soc. Lond. B 270, 2111–2116 (2003)
Weimerskirch, H., Inchausti, P., Guinet, C. & Barbraud, C. Trends in bird and seal populations as indicators of a system shift in the Southern Ocean. Antarct. Sci. 15, 249–256 (2003)
Thompson, P. M. & Ollason, J. C. Lagged effects of ocean climate on fulmar population dynamics. Nature 413, 417–420 (2001)
De Valpine, P. & Hastings, A. Fitting population models incorporating process noise and observation error. Ecol. Monogr. 72, 57–76 (2002)
Micol, T. & Jouventin, P. Long term population trends in seven Antarctic seabirds at Pointe Géologie (Terre Adélie). Polar Biol. 24, 175–185 (2001)
Shumway, R. H. Applied Statistical Time Series Analysis (Prentice-Hall, Englewood Cliffs, New Jersey, 1988)
We thank A. P. Møller for help in organizing this database and for comments on the manuscript. This study was supported by the Research Council of Norway (Strategic University Programme in Conservation Biology), the Natural Sciences and Engineering Research Council of Canada, the Institut Polaire francais-program 109 and the US National Science Foundation.
Reprints and permissions information is available at npg.nature.com/reprintsandpermissions. The authors declare no competing financial interests.
The estimates of the total strength of density dependence, the autoregression coefficients for different time lags, the stationary variance in the time series and the environmental variance (including transient fluctuations due to variation in the age-distribution) for the time series. The estimates of the life history characters clutch size, age at maturity and adult survival rates are also included. (PDF 21 kb)
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Sæther, BE., Lande, R., Engen, S. et al. Generation time and temporal scaling of bird population dynamics. Nature 436, 99–102 (2005). https://doi.org/10.1038/nature03666
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