Norges teknisk-naturvitenskapelige universitetFakultet for informasjonsteknologi, matematikk og elektroteknikkInstitutt for matematiske fag

Steinar Engen

Professor in biostatistics/biomodelling - Centre for Biodiversity Dynamics - Advisor at NINA

Deptartment of Mathematical Sciences, NTNU;
Phone: +47 735 91747; Fax: +47 7359 3524;
Visiting address: SII-1229

Research interests:

Stochastic modelling and statistics in ecology and conservation biology

  • Stochastic dynamics for single species
  • Spatial stochastic population dynamics
  • Stochastic abundance models and community structure
  • Population viability analysis
  • Optimal harvesting in a stochastic environment
  • Genetic drift in fluctuating populations
  • Selection in fluctuating age-structured populations

Lecturing since 2003:

Publications before 1984

    1. Strømgren, T., Lande, R. and Engen, S. (1973). Intertidial distribution of the fauna on muddy beaches in the Borgenfjord area. Sarsia 53: 49-70.

    2. Engen, S. (1974). On species frequency models. Biometrika 61: 263-70.( pdf )

    3. Engen, S. (1975). A note on the geometric series as a species frequency model. Biometrika 62: 697-99.

    4. Engen, S. (1975). The coverage of a random sample from a biological community. Biometrics 31: 201-8.

    5. Engen, S. (1976). A note on the estimation of the species area curve. J.Cons.Int. Explor.Mer. 36: 286-88.

    6. Engen, S. (1977). Exponential and logarithmic species area curves. Am. Nat. 111: 591-94.

    7. Engen, S. (1977). Comments on two different approaches to the analysis of species frequency data. Biometrics 33: 205-13.

    8. Engen, S. and Thaillie, C. (1978). A basic development of abundance models. The proceedings of the second international ecological congress, satelite program in statistical ecology, Vol. 4, pp. 289-311.

    9. Engen, S. (1978). Abundance models; sampling and estimation. The proceedings of the second international ecological congress, satelite program in statistical ecology, Vol. 4, pp. 313-32.

    10. Engen, S. (1978). Stochastic abundance models with emphasis on biological communities and species diversity. Chapman & Hall, London. In the series: Monographs on applied probability and statistics, eds. M.S.Bartlett and D.R.Cox.

    11. Engen, S. (1979). Some basic concepts of ecological equitability. The proceedings of the second international ecological congress, satelite program in statistical ecology, Vol. 6, pp. 37-50.

    12. Engen, S. (1979). Stochastic abundance models in ecology. Biometrics 35: 331-38 (invited paper)

    13. Aagaard, K. and Engen, S. (1980). Species diversity of Chironimid Communities. Acta. Univ. Caralinae 12: 5-12.

    Publications 1984-1993

    14. Engen, S. and Stenseth, N.C. (1984). A general verion of optimal foraging theory: the effect of simultanious encounter. Theor. pop. biol. 26: 192-204.

    15. Engen, S. and Stenseth, N.C. (1984). An ecological paradox: A food type may become more rare in the diet as a consequence of being more abundant. Am Nat. 124: 352-59.

    16. Engen, S., Järvi, T. and Wicklund, C. (1984). The evolution of aposematic colouration by individual selection. Oikos 46: 397-403.

    17. Engen, S. (1984). The association between pairs of species on discrete habitable islands. Biometrics 40: 729-38.

    18. Engen, S. (1984). A comment on stochastic approaches to optimal foraging theory. Ecology 65: 652-54.

    19. Engen, S., Nørseth, S. og Wibe, J. (1984). Matematikk - databehandling i skolen. Nordisk matematisk tidsskrift 32: 55-63.

    20 Framstad, E., Engen, S. and Stenseth (1984). Regression analysis, residual analysis and missing variables in regression analysis. Oikos 44: 319-23.

    21. Nilsen, A. and Engen, S. (1985). A statistical procedure for counting alveolar macrofages. British Journal of Industrial Medicine 42: 205-8.

    22. Engen, and Sæther, B.-E. (1985). The evolutionary significance of sexual selection. J. Theor. Biol. 117: 277-89.

    23. Slagsvold, T., Røskaft, E. and Engen, S. (1986). Sex ratio, differential cost of rearing young, differential mortality between the sexes during period of parental care: Fisher's theory applied to birds. Ornis Scandinavika 17: 117-25.

    24. Engen, S. and Seim, E. (1987). Optimal invariant stopping rules. J. Appl. Prob. 24: 77-87.

    25. Iversen, O.J. and Engen, S. (1987). Aspekter ved AIDS-epidemien, noen regneeksempler. Tidsskriftet for den norske legeforening 19,20,21: 1598-1600.

    26. Iversen, O.J. and Engen, S. (1987). The epidemiology of AIDS - statistical analysis. Journal of epidemiology and community health 41: 55-58.

    27. Engen, S., Sæther, B.-E. and Stenseth, N.C. (1988). The effect of competition on the ranking of food items. Am. Nat. 132: 629-42.

    28. Engen, S. and Sæther, B.-E. (1988). Optimization of constrained life histories: some generalizations. J. Theor. Biol. 130: 229:37

    29. Engen, S. and Stenseth, N.S. (1989). Age-specific optimal diets and optimal faraging tactics. A life-historic approach. Theor. pop. biol. 36: 281-95.

    30 Sæther, B.-E. Engen, S. and Andersen, R. (1989). Resource utilization of moose Alces alces during winter: Constraints and options. Finnish Game res. 46: 79-86.

    31. Vivås, H.J. and Engen, S. (1991). Estimation of circadian activity pattern when the beginning and end of active periods are not always observable. Biometrics 47: 1547-56.

    32. Engen, S. (1992). Sexual mixing models; A comparison between analogue deterministic and stochastic models. Math. Biosc. 108: 279-97. ( pdf )

    33. Yoccoz, N., Engen, S. and Stenseth, N.C. (1993). Optimal foraging: The importance of environmental uncertainty and accuracy in parameter estimation. Am. Nat. 141: 139-57.

    Publications 1994-1997

    34. Engen, S. and Sæther, B.-E. (1994). Optimal allocation of resources to growth and reproduction. Theor. pop. biol. 46: 232-48.

    35. Langvatn. R., Bakke, Ø. and Engen, S. (1994). Retrospective studies of read dear reproduction using regressing luteal structures. The Journal of Wildlife management 58: 654-63.

    36. Bevanger, K., Bakke, Ø. and Engen, S. (1994). Corpse removal experiments with Willow Ptarmigan (Lagopus lagopus) in power-line corridors. Õkol. Võgel 16: 597-607.

    37. Lande, R., Engen, S. and Sæther, B.-E. (1994): Optimal harvesting, economic discounting and extinction risk in fluctuating populations. Nature 372:88-90.

    38. Lande, R., Engen, S. and Sæther, B.E. (1995): Optimal harvesting of populations with a risk of extinction. Am. Nat. 145: 728-45.

    39. Sæther, B.-E., Engen, S. and Lande, R. (1995). Density-dependence and optimal harvesting of fluctuating populations. Oikos 76: 40-46.

    40. Engen, S. and Lande, R. (1996). Population dynamic models generating the lognormal species abundance distribution. Math. Biosc. 132: 169-84.( pdf )

    41. Engen, S. and Lande, R. (1996). Population dynamic models generating species abundance distributions of the gamma type. J. Theor. Biol. 178: 325-31.( pdf )

    42. Tufto, J., Engen, S. and Hindar, K. (1996). Inferring patterns of migration from gene frequencies under equilibrium conditions. Genetics 144: 1909-19.

    43. Engen, S., Lande, R. and Sæther, B.-E. (1997). Harvesting strategies for fluctuating populations based on uncertain population estimates. J. Theor. biol. 186:201-12.( pdf )

    44. Engen, S. and Lillegård, M. (1997). Statistical simulations conditioned sufficient statistics. Biometrika 84: 235-40..

    45. Tufto, J., Engen, S. and Hindar, K. (1997). Stochastic processes in dispersal of airborn seed and pollen. Theor. pop. biol. 52:16-26. ( pdf )

    46. Lande, R., Sæther, B.-E., Engen, S. (1997). Threshold harvesting and sustainability of fluctuating resources. Ecology 78: 1341-50..

    Publications 1998-2000

    47. Engen, S., Bakke, Ø. and Islam, A. (1998). Demographic and environmental stochasticity - concepts and definitions. Biometrics 54: 39-45. ( pdf )

    48. Sæther, B.-E., Engen, S., Islam, A., McCleery, R. and Perrins, C. (1998). Environmental stochasticity and extinction risk in a population of small song bird, the great tit. Am. Nat. 151:441-50.

    49. Tufto, J., Raybould, A.F., Hindar, K. and Engen, S. (1998). Genetic structure and dispersal pattern in sea beet. Genetics 149: 1975-85. ( pdf )

    50. Sæther, B.-E., Engen, S., Swenson, J.E., Bakke, Ø. and Sandgren, F. (1998). Viability of scandinavian brown bear Ursus Arctos populations: The effect of uncertain parameter estimates. Oikos 83: 403-16.

    51. Lande, R., Engen, S. and Sæther, B.-E. (1998). Extinction times in finite metapopulation models with stochastic local dynamics. Oikos 83: 383-89.

    52. Engen, S. and Sæther, B.-E. (1998). Stochastic population models: Some concepts, definitions and results. Oikos 83: 345-52.

    53. B.-E. Sæther and S. Engen (eds.).1998. Population dynamics in a stochastic environment: theory and facts. Proceedings of an Oikos seminar held at Røros, Norway, 4-7 April, 1997. Oikos 83: 343-416.

    54. Sæther, B.-E., Engen, S. and Lande, R. 1999. Finite metapopulation models with density-dependent migration and stochastic local dynamics. Proc. Roy. Soc. Ser. Lond. B. 266: 113-118..

    55. Lillegård, M. and Engen, S. (1999). Exact confidence intervals generated by conditional parametric bootstrapping. J. appl. statistics: 26:447-59.

    56. Lande, R., Engen, S. and Sæther, B.-E. (1999). Spatial scale of population synchrony: correlation versus dispersal and density regulation. Am. Nat. 154: 271-81 ( pdf ).

    57. Tufto, J., Sæther, B.-E., Engen, S.,Swenson, J.E. and Sandegren, F. (1999). Harvesting strategies for conserving minimum viable populations based on World Conservation Union criteria: brown bears in Norway. Proceedings of the Royal Society London. Series B. 266: 961-67.

    58. Tufto, J., Sæther, B.-E, Engen, S., Arcese, P., Jerstad, K., Røstad, O.W. and Smith, J.N.M.(2000). Bayesian meta-analysis of demographic parameters in three small temperate passerines. Oikos 88: 273-81.

    59. Sæther, B.-E-, Tufto, J., Engen, S., Jerstad, K. Røstad, O.W.and Skåtan, E. (2000). Population dynamic consequencies of climate change in a small temperate songbird, the dipper. Science 287: 854-856 .

    60. Diserud, O. H., and Engen, S. (2000). A general and dynamic species abundance model, embracing the lognormal and the gamma models. The American Naturalist. 155: 497-511.

    61. Engen, S. and Sæther, B.-E. (2000). Predictions in Brownian motions applied to population viability analysis. Journal of theoretical biology 205: 649-658.( pdf )

    62. Sæther, B.-E., Engen, S., Lande, R., Arcese, P. and Smith, J.N.M. (2000). Estimating time to extinction in an island population of song sparrows. Proceedings of the Royal Society B 267: 621-626.

    63. Ødegaard, F., Diserud, O.H., Engen, S. and Aagaard, K. (2000). The magnitude of local host specificity for phytophagous insects. Conservation Biology 14: 1182-86.( pdf )

    Publications 2001-2002

    64. Lande, R., Sæther, B.-E. and Engen, S. (2001). Sustainable exploitation of fluctuating populations. In Conservation of exploited species, D.J. Reynolds, G.M. Mace, K.H. Redford and J.G. Robinson, eds. Cambridge University press.

    65. Engen, S. (2001). A dynamic and spatial model with migration generating the log-Gaussian field of population densities. Mathematical Biosciences 173: 85-102.( pdf )

    66. Sæther, B.-E., Engen, S. and Solberg, E.J. (2001). Optimal harvesting of age-structured populations of moose in a fluctuationg environment. Wildlife Biology 7:171-179.

    67. Engen, S., Sæther, B.-E. and Møller, A.P. (2001). Stochastic population dynamics and time to extinction of a declining population of barn swallow. J.Anim.Ecol. 70: 789-797.( pdf )

    68. Sæther, B.-E. and Engen, S. (2002). Including stochasticity in population viability analysis. In Population Viability Analysis, Steven R. Beissinger and Dale R. McCullough, editors. University of Chicago Press, Chicago, Illinois.

    69. Engen, S., B.-E. Sæther and R. Lande (2002). Migration and spatio-temporal variation in population dynamics in a heterogeneous environment. Ecology 83:570-579.

    70. Aanes, S., Engen, S. and Sæther, B.-E. (2002). Sustainable harvesting strategies of willow grouse (Lagopus lagopus) in a fluctuating environment. Ecological Applications 12:281-290.

    71. Lande, R, Engen, S. ,Sæther, B.-E., Filli, F. and Matthysen,E. 2002. Estimating density dependence from population time series using demographic theory and life history data. American Naturalist 159:321-337.

    72. Engen, S., Lande, R., Walla,T. and DeVries, P.J. (2002). Analysing spatial structure of communities by the two-dimensional Poisson lognormal species abundance model. American naturalist 160: 60-73. ( pdf )

    73. Sæther, B-.E., Engen, S. and Matthysen, E. (2002). Demographic characteristics and population dynamical patterns of solitary birds. Science 295:2070-73.

    74. Engen, S., Lande, R.- and Sæther, B.-E. 2002 . The spatial scale of population fluctuations and quasi-extinction. American Naturalist 160: 439-451.( pdf )

    75. Lande, R., Engen, S. and Sæther, B.-E. 2002. Estimating density-dependence in age-structured populations. Phil. Trans. R. Soc. Lond. B 357: 1179-1184.

    76. Sæther, B.-E., and S. Engen. 2002. Patterns of variation in avian population growth rates. Phil. Trans. R. Soc. Lond. B 357:1185-1195.

    77. Sæther, B.-E., Engen, S, Lande, R., Both, C. And Visser, M.E. 2002. Density-dependence and stochastic variation in the dynamics of newly established small songbird population. Oikos 99: 331-337.

    78. Sæther, B.-E., Engen, S., Filli, F., Aanes, R., Schröder, W. And Andersen, R. 2002. Contrasting stochastic population dynamics of two introduced Swiss populations of Ibex. Ecology 83: 3457-3465.

    Publications 2003-2004

    79. Lindqvist,B., Taraldsen, G., Lillegård, M. And Engen, S. (2003). A counterexample to a claim about stochastic simulations. Biometrika 90:489-90.

    80. Lande, R., Engen, S. and Sæther, B.-E. 2003. Stochastic population dynamics in ecology and conservation. Oxford University Press. Oxford.

    81. Engen, S., Lande, R. and Sæther, B.-E. 2003. Demographic stochasticity and Allee effects in populations with two sexes. Ecology 84:2378-2386.

    82. Sæther, B.E. and Engen, S. 2003. The routes to extinction. In: T. Blackburn and K. Gaston (eds.), pp. 218-236. Macroecology. Blackwell Publ., Oxford.

    83. Sæther, B.-E. and Engen, S. 2003. Pattern of variation in avian population growth rates. In: R.M. Sibly, J. Hone and T.H. Clutton-Brock (eds.), pp. 66-84. Cambridge University Press, Cambridge.

    84. Engen, S. 2003. Stokastisk modellering i økologi og bevaringsbiologi. Akademiets årbok.

    85. Sæther, B.-E., Engen, S. , Møller, A.P. et al. 2003. Climate variation and regional gradients in population dynamics of two hole nesting passerines. Proceedings of the Royal Society London. Series B. 270: 2397-2404.

    86. Lande, R., Engen, S. and Sæther, B.-E. 2003. Estimating density dependence in time-series of age-structured populatiobs, pp. 55-65. Cambridge University Press, Cambridge.

    87. Sæther, B.-E., Sutherland, W.J. and Engen, S. 2004 Climate influences on avian population dynamics. Advances in Ecological Research 35:185-209.

    88 Sæther, B.-E. and Engen, S. 2004. Stochastic population theory faces reality in the laboratory. Trends in Ecology and Evolution 19: 351-353.

    89. Sæther, B.-E., Engen, S., Lande, R., Møller, A.P., Bensch, S.,Hasselquist, D.,Beier, J. And Liesler, B. 2004. Time to extinction in relation to mating system and type of density regulation in populations with two sexes. Journal of Animal Ecology 73: 925-934. ( pdf )

    90. Walla, T.R., Engen, S., DeVries, P.J. and Lande, R. 2004. Modeling vertical beta-diversity in tropical butterfly communities. Oikos 107: 610-618. ( pdf )

    91. Sæther, B.-E., Engen, S., Møller, A.P., Visser, M.E., Matthysen, E., Fiedler, W., Freckleton, R., Lambrechts, M.M., Becker, P.H., Brommer,J., Dickinson, J., Gehlbach, F.R., Merilä, J., Rendell, W., Thomsen, D. and Török, J. 2004. Time to extinction of bird populations. Ecology 86: 693-700.

    Publications 2005-2006

    92. Grøtan, V., Sæther, B.-E., Engen, S., Solberg, E.J., Linnell, J.D.C., Andersen, R., Brøseth, H. and Lund, E. 2005. Climate causes large scale spatial synchrony in population fluctuations of a temperate herbivore. Ecology 86: 1472-1482. ( pdf )

    93. Engen, S., Lande, S., Sæther, B.E. and Bregnballe, T. 2005. Estimating patterns of synchrony in fluctuating populations. Journal of Animal Ecology 74:601-611. ( pdf )

    94. Sæther, B.E., Engen, S., Møller, A.P., Weimerskirch, H., Visser, M.E., Fiedler, W., Matthysen, E., Lambrechts, M.M., Badyaev, A., Becker, P.H., Brommer, J.E., Bukacinsky, D., Bukacinsky, M., Christensen, H., Dickinson, J., Du Feu, C., Gehlbach, F.R., Heg, D., Hötker, H., Merilä, J., Nielsen, J.T., Rendell, W., Robertson, R.J., Thomsen, D.L., Török, J. and Van Hecke, P. 2005. Life history variation predicts the effects of demographic stochasticity on avian population dynamics. American Naturalist 164:793-802.( pdf )

    95. Engen, S., Lande, R., Sæther, B.-E. and Weimerskirch, H. 2005. Extinction in relation to demographic and environmental stochasticity in age-structured models. Mathematical Biosciences 195:210-227.( pdf )

    96. Lillegård, M., Engen, S. and Sæther, B.-E. 2005. Bootstrap method for estimating spatial synchrony in fluctuating populations. Oikos 109:342-350. ( pdf )

    97. Lillegård, M, Engen, S., Sæther, B.-E. and Toresen, R. 2005.Harvesting strategies for Norwegien spring spawning herring. Oikos 110: 567-577. ( pdf )

    98. Engen, S., Lande, R. and Sæther, B.-E. 2005. Effective Size of a Fluctuating Age-Structured Population. Genetics 170: 941-954. ( pdf )

    99. Sæther, B.-E., Lande, R., Engen, S., Lillegård, M. et al. 2005. Generation time and temporal scaling of bird population dynamics. Nature 436:99-102 . ( pdf )

    100. Engen, S and Sæther, B.-E. 2005. Generalizations of the Moran effect explaining spatial synchrony in population fluctuations. American Naturalist 166:603-612 ( pdf ).

    101. Lillegard M, Engen S, Saether BE. 2005. Bootstrap methods for estimating spatial synchrony of fluctuating populations: an addendum OIKOS 110 : 629-629 ( pdf ).

    102. Sæther, B.-E., Engen, S., Persson, J., Brøseth, H., Landa, A. And Willebrand, T. 2005. Management strategies of Fennoscandian wolverines. Journal of Wildlife management 69: 1001-1014.

    103. Asbjørnsen, E.J., Sæther, B.-E., Linnell, J.D.C., Engen, S., Andersen, R. And Bretten, T. 2005. Predicting the growth of a small introduced muskox population using population prediction intervals. Journal of Animal Ecology 74: 612-618 . ( pdf )

    104. Sæther, B.-E., Grøtan, V., Tryjanowski, P., Barbraud, C., Engen, S. and Fulin, M. 2006. Climate and spatio-temporal variation in the population dynamics of a long distance migrant, the white stork. Journal of Animal Ecology 75:80-90.( pdf ).

    105. Lande, R., Engen, S., Sæther, B.-E. and Coulson, T. 2006. Estimating Density Dependence from Time Series of Population Age Structure. American Naturalist 168:76-87 ( pdf ).

    106. Ringsby, T.H., Sæther, B.-E., Jensen, H. and Engen, S. 2006. Demographic Characteristics of Extinction in a Small Insular House Sparrow Population in Northern Norway. Conservation Biology 20:1761-1767 (pdf)

    Publications 2007

    107. Engen,S., Lande, R., Sæther, B.-E. and Festa-Bianchet, M. 2007. Using reproductive value to estimate key parameters in density-independent age-structured populations. Journal of Theoretical Biology 244:308-317 ( pdf ).

    108. Engen, S. 2007. Stochastic growth and extinction in a spatial geometric Brownian population model with migration and correlated noise. Mathematical Biosciences 209: 240-255 ( pdf ).

    109. Sæther, B.-E., Lillegård, M., Grøtan, V., Filli, F. and Engen, S. 2007. Predicting fluctuations of re-introduced ibex populations: the importance of density-dependence, environmental stochasticity and uncertain population estimates. Journal of animal ecology 76:326-336 ( pdf ).

    110. Sæther, B.-E., Engen, S., Grøtan, V., Fiedler, W., Matthysen, E., Visser, M. E., Wright, J., Møller, A. P., Adriaensen, F., van Balen, H., Balmer, D., Mainwaring, M. E., McCleery, R. H., Pampus, M. and Winkel, W. 2007. The extended Moran effect and large-scale synchronous fluctuations in the size of great tit and blue tit populations. Journal of Animal Ecology 76: 315-325 ( pdf ).

    111. Sæther, B-.E., Engen, S., Solberg, E.J. and Heim, M. 2007. Estimating the growth of a newly established moose population using reproductive value. Ecography 30: 417-421 ( pdf ).

    112. Engen, S., Ringsby, T.H., Sæther, B.-E., Lande, R., Jensen, H. 2007. Effective size of fluctuating populations with two sexes and overlapping generations. Evolution 61: 1873-1885 ( pdf ).

    113. Aanes, S., Engen, S., Sæther, B.-E., Aanes, R. 2007. Estimation of fish stock dynamical parameters from catch-at-age data and indices of abundance: can natural and fishing mortality be separated? Canadian Journal of Fisheries and Aquatic Sciences 64: 1130-1142 ( pdf ).

    114. Engen, S. 2007. Heterogeneity in dynamic species abundance model: the selective effect of extinction processes. Mathematical Biosciences 210: 490-507 ( pdf ) .

    115. Engen, S. 2007. Heterogeneous communities with lognormal species abundance distribution: species-area curves and sustainability. Journal of Theoretical Biology 249: 791-803 ( pdf ) .

    116. Lie, A. M., Engen, S. and Sæther, B.-E. 2007. Understanding Mating Systems: A Mathematical Model of the Pair Formation Process. Theoretical Population Biology 73:112-124.

    Publications 2008-2009

    117. Lillegård, M., Engen, S., Sæther, B.-E., Grøtan, V. and Drever, M. C. 2008. Hierarchical Bayesian methods and estimation of population parameters from areal counts of North-American mallards: A cautionary tale. Ecological Applications 18: 197-207.

    118. Beissinger, S. R., Wunderle jr., J. M., Meyers, J. M., Sæther, B.-E. and Engen, S. 2007. Atonomy of a bottleneck: Diagnosing factors limiting population growth in the Puerto Rican parrot. Ecological monographs 78: 1197-1208.

    119. Grotan V, Sæther B-E, Filli F and Engen S. 2008. Effects of climate on population fluctuations of ibex. Global Change Biology 14:218-228.

    120. Vindenes, Y., Engen, S. and Sæther, B.-E. 2008. Individual heterogeneity in vital parameters and demographic stochasticity. American naturalist 171:455-467.

    121. Engen, S., Lande, R. and Sæther, B.-E. 2008. A general model for analysing Taylor's spatial scaling laws. Ecology 89: 2612-2622 ( pdf ).

    122. Engen, S., Sæther, B.-E., Sverdrup-Thygeson, A., Grøtan, V. and Ødegaard, F. 2008. Assessment of species diversity from species abundance distributions at different localities. Oikos 117:738-748 ( pdf ).

    123. Sæther, B.-E., Engen, S., Grøtan, V., Bregnballe, T., Both, C., Tryjanowski, P., Leivits, A., Wright, J., Møller, A. P., Visser, M. E., and Winkel, W. 2008. Forms of density regulation and (quasi-) stationary distributions of population sizes of birds. OIKOS 117: 1197-1208 ( pdf ) .

    124. Sæther, B.-E., Lillegård, M., Grøtan, V., Drever, M., Engen, S., Nudds, T., Podruzny, K. 2008. Geographical gradients in the population dynamics of north american prairie ducks. Journal of Animal Ecology 77: 869-882.

    125. Engen, S, Grøtan, V., Halley, D. and Nygård, T. 2008. An efficient multivariate approach for estimating preference when individual observations are dependent. Journal of Animal Ecology 77: 958-965.

    126. Jonsson, B., N. Jonsson, K. Hindar, T.G. Northcote and S. Engen. 2008. Asymmetric competition drives lake use of coexisting salmonids. Oecologia 157: 553-560 ( pdf ).

    127. Grøtan, V., Saether, B.-E., , Engen, S., Van Balen, J. H., Perdeck, A.C. and M. Visser, 2008. Spatial and temporal variation in the relative contribution of density dependence, climate variation and migration to fluctuations in the size of great tit populations. Journal of Animal Ecology 78:447-459.

    128. Engen, S., Lande, R. and Sæther, B.-E. 2009. Fixation probability of beneficial mutations in a fluctuating population. Genetics research 91:73-82 ( pdf ).

    129. Steinnes, E., Gaare, E. and Engen, S. 2009. Influence of soil acidification in southern Norway on the 137Cs exposure of moose? Science of the Total Environment 407: 3905-3908.

    130. Lande, R., Engen, S. and Sæther, B.-E. 2009. An evolutionary maximum principle for density-dependent population dynamics in a fluctuating environment Phil. Trans. Roy. Soc. Phil. Trans.R. Soc. B 364: 1511-1518 ( pdf ).

    131. Sæther, B.-E., Grøtan, V., Engen, S., Noble, D., and Freckleton, R. 2009. Ctitical parameterts for predicting population fluctuations of some British passerines. Journal of Animal Ecology 78: 1063-1075.

    132. Sæther, B.-E., Engen, S. and Solberg, E. 2009. Effective size of harvested ungulate populations. Animal Conservation 12: 488-495 ( pdf ).

    133. Engen, S., Lande, R, and Sæther, B.-E. 2009. Reproductive Value and Fluctuating Selection in an Age-Structured Population. Genetics 183: 629–637 ( pdf ).

    134. Grøtan, V., Sæther, B.-E., Lillegård, M., Solberg, E.J. and Engen, S. 2009. Geographical variation in the influence of density dependence and climate on the recruitment of Norwegian moose. Oecologia 161: 685-695.

    135. Engen, S., Lande, R., Sæther, B.-E. and Dobson, F. S. 2009. Reproductive value and the stochastic demography of age-structured populations. American Naturalist 174: 795–804 ( pdf ).

    Publications 2010-2011

    136. Vindenes,Y., Lee, A.M., Engen, S. and Sæther, B.-E. 2010. Fixation of slightly beneficial mutations: Effects of life history. Evolution 64: 1063-1075.

    137. Sæther, B.-E. and Engen, S. 2010. Population analyses. In Effects of climate change on birds. Møller, A.P., Fiedler, W. and Berthold, P. eds., chapter 7, pp 67-76. Oxford University Press, Oxford, UK.

    138. Sæther, B.-E. and Engen, S. 2010. Population consequencies of climate change. In Effects of climate change on birds. Møller, A.P., Fiedler, W. and Berthold, P. eds., chapter 14, pp 191-212. Oxford University Press, Oxford, UK.

    139. Engen, S., Lande, R., Sæther, B.-E. and Gienapp, P. 2010. Estimating the ratio of effective to actual size of an age-structured population from individual demographic data. Journal of Evolutionary Biology 23: 1148–1158.

    140. Van de Pol, M., Vindenes, Y., Sæther, B.-E., Engen, S., Ens, B. J., Oosterbeek, K. and Tinbergen, J. M. 2010. Effects of climate change and variability on population dynamics in a long-lived shorebird. Ecology 91: 1192-1204 ( pdf ).

    141. Sæther, B.-E., Engen, S., Odden, J., Linnell, J.D.C., Grøtan, V., Andersen, R. and Andrén. 2010. Sustainable harvest strategies for age-structured Eurasian lynx populations: The use of reproductive value. Biological Conservation 143: 1970-1979.

    142. Engen, S., Grøtan, V. and Sæther, B.-E. 2011. Estimating similarity of communities: a parametric approach to spatio-temporal analysis of species diversity. Ecography 34:220-231 ( pdf )

    143. Sæther, B.E., Grøtan, V., Engen, S., Noble, D.G. and Robert, P. 2011. Rarity, life history and scaling of the dynamics in time and space of British birds. Journal of Animal Ecology 80: 215-224.

    144. Vindenes, Y., Engen, S. and Sæther, B.E. 2011. Integral projection models for finite populations in a stochastic environment. Ecology 92: 1146-1156.

    145. Lee, A.M. Engen, S. and Sæther, B.E. 2011. Demographic stochasticity, Allee effects and extinction: the influence of mating system and sex ratio. The American Naturalist 177:301-313.

    146. Engen, S., Aagaard, K and Bongard, T. 2011. Disentangling the effects of heterogeneity, stochastic dynamics and sampling in a community of aquatic insects. Ecological Modelling 222: 1387-1393.

    147. Lee, A.M. Engen, S. and Sæther, B.E. 2011. The influence of persistent individual differences and age at maturity on effective population size. Proceedings of the Royal Society, B. (in press) ( pdf ) .

    148. Certain, G., Skarpaas, O., Bjerke, J.W., Framstad, E., Lindholm, M., Nielsen, J.E., Norderhaug, A., Oug, E., Perdersen, H.C., Schartau, A.K., Storaunet, K.O., Van der Meeren, G., Aslaksen, I., Engen, S., Garnåsjordet, P.A., Kvaløy, P., Lillegård, M., Yoccoz, G., and Nybø, S. 2011. The nature index: a general framework to synthesize knowledge on the state of biodiversity. 2011. PLoS ONE 6(4): e18930. doi:10.1371/journal.pone.0018930 ( pdf )

    149. Van de Pol, M., Vindenes, Y., Sæther, B.-E., Engen, S., Ens, B. J., Oosterbeek, K. and Tinbergen, J. M. 2011. Poor environmental tracking can make extinction insensitive to the colour of environmental noise. Proceedings of the Royal Society 278: 3713-3722.

    150. Engen, S., Lande, R. and Sæther, B.-E. 2011. Evolution of a plastic quantitative trait in an age-structured population in a fluctuating environment. Evolution 65: 2893-2906.

    Publications 2012-2013

    151. Vindenes, Y., Sæther, B.-E. and Engen, S. 2012. Effects of demographic structure on key properties of stochastic density-independent population dynamics. Theoretical Population Biology 82: 253-263 ( pdf ) .

    152. Grøtan, V., Lande, R., Engen, S., Sæther, B.-E. and DeVries, P.J. 2012. Seasonal cycles of species diversity and similarity in a tropical butterfly community. Journal of Animal Ecology 81:714-723.

    153. Bellier, E., Grøtan, V. and Engen, S. 2012. Combining counts and incidence data: an efficient approach for estimating the species abundance distribution and diversity indices. Oecologia 170: 477-488 ( pdf )

    154. Engen, S., Sæther, B.-E., Kvalnes, T and Jensen, H. 2012. Estimating fluctuating selection in age-structured populations. Journal of Evolutionary Biology 25: 1487-1499.

    155. Tufto, J., Lande, R., Ringsby, T.-H., Engen, S., Sæther, B.-E., Walla, T.R. & DeVries, P.J. 2012. Estimating Brownian motion dispersal rate, longevity and population density from spatially explicit mark-recapture data on tropical butterflies. Journal of Animal Ecology 81: 756-769.

    156. Bjørkvoll, E., Grøtan, V., Aanes, S., Sæther, B.-E., Engen, S. and Aanes, R. 2012. Stochastic population dynamics and life history variation in marine fish species. American Naturalist 180: 372-387.

    157. Sandvik, H., Sæther, B.-E., Holmern, T., Tufto, J. and Engen, S. 2013. Generic Ecological Impact Assessments of Alien Species in Norway: A Semi-Quantitative Set of Criteria. Biodiversity and Conservation 22: 37-62.

    158. Linnerud, M., Sæther, B.-E., Grøtan, V., Engen, S., Noble, D. G. and Freckleton, R.P. 2013. Interspecific differences in stochastic population dynamics explains variation in Taylor’s temporal power law. Oikos 122: 1207-1216.

    159. Engen, S., Sæther, B.-E., Armitage, K. B., Blumstein, D. T., Clutton-Brock, T. H., Stephen Dobsen, F., Fiesta-Bianchet, M., Oli, M. K., and Ozgul, A. 2013. Estimating the effect of temporally autocorrelated environments on the demography of density-independent age-structured populations. Methods in Ecology and Evolution 4: 573-584.

    160. Engen, S., Lande, R. and Sæther, B.-E. 2013. A quantitative genetic model of r- and K-selection in a fluctuating population. The American Naturalist 181:725-736.

    161. Sæther, B.-E., Engen, S. and Grøtan, V. 2013. : Species diversity and community similarity in fluctuating environments: parametric approaches using species abundance distributions. Journal of Animal Ecology 82: 721-738 ( pdf ).

    162. Solbu, E. B., Engen, S. and Diserud, O. 2013. Changing environments causing time delays in population dynamics. Mathematical Biosciences 244: 213-223.

    163. Sæther, B.-E., Grøtan, V., Engen, S. 2013. How life history influences population dynamics in fluctuating environments. American Naturalist 182: 743-759.

    Publications 2014-

    164. Bellier, E., Grøtan, V., Engen, S., Schartau, A-.K., Herfindal, I. and Finstad, A.G. 2014. Distance decay of similarity, effects of environmental noise and heterogeneity among species in the spatio-temporal dynamics of a dispersal-limited comunity. Ecography 37: 172-182.

    165. Engen, S. and Sæther, B.-E. 2014. Evolution in fluctuating environments: decomposing selection into additive components of the Robertson-Price equation. Evolution 68: 854-65.

    166. Engen, S., Kvalnes, T. and Sæther, B.-E. 2014. Estimating phenotypic selection in age-structured populations by removing transient fluctuations. Evolution 68:2509-2523.

    167. Bartzke, G., May, R., Stokke, S., Røskaft, E., and Engen, S. 2014. Comparative effects of power lines and roads on moose (Alces alces) habitat selection. In Proceedings of the Environmental Concerns in Right-of-Way Management: 10'th International Symposium. Phoenix, Arizona, USA (in press).

    168. Magdalena Lee, A.M., Sæther, B.E., Hansen, B.B., Bjørkvoll, E.M., Grøtan, V., Engen, S., Albon, S., Stien, A., and Loe, L.E.. 2014. An integrated population model for a long-lived ungulate: more efficient data use with Bayesian methods. Oikos (in press).

    169. Engen, S., Lande, R. and Sæther, B.-E. 2014. Evolutionary Consequences of Nonselective Harvesting in Density-Dependent Populations. The American Naturalist 184: 714-726.

    170. Sæther, B-.E. and Engen, S. 2015. The concept of fitness in fluctuating environments. Trends in Ecology and Evolution (in press).

    171. Sæther, B-.E. and Engen, S. 2015. The theory of r and K selection in deterministic, stochastic environments and density-dependent environments. Encyclopedia of Evolutionary Biology. Elsevier (in press).