Population changes are believed to be controlled by multiple factors, including an important density-dependent effect. This paper reviews the literature on this topic and shows that this density-dependent effect does not exist. This paper also gives a typical example in which no density-dependent effect was detected in the stock-recruitment relationship in Japanese sardines. The recruitment was found to be determined in proportion to the spawning stock biomass and to be affected by environmental factors. This simple mechanism is applicable not only in fish species but also in insects such as Thrips imaginis in Australia. The reason that many biologists have not become aware that the density-dependent effect does not exist is discussed using a metaphor. This paper proposes a new concept in the study of population change. The new concept proposed here will replace the currently used basic concept that has been assumed to be correct for more than 50 years.
Davidson, J. and Andrewartha, H.G. (1948) Annual Trends in a Natural Population of Trips Imagines (Thysanoptera). Journal of Animal Ecology, 17, 193-199. http://dx.doi.org/10.2307/1484
Davidson, J. and Andrewartha, H.G. (1948) The Influence of Rainfall, Evaporation and Atmospheric Temperature on Fluctuations in the Size of a Natural Population of Thrips imaginis (Thysanoptera). Journal of Animal Ecology, 17, 200-222. http://dx.doi.org/10.2307/1485
Nicholson, A.J. and Bailey, V.A. (1935) The Balance of Animal Populations. Part I. Proceedings of the Zoological Society of London, 105, 551-598. http://dx.doi.org/10.1111/j.1096-3642.1935.tb01680.x
Huffaker, C.B. (1958) The Concept of Balance in Nature. Proceeding Tenth Internet. Congress of Entomology, 2, 625- 636.
Smith, F.E. (1961) Density Dependence in the Australian Thrips. Ecological Society of America, 42, 403-407. http://dx.doi.org/10.2307/1932093
Sibly, R.M., Barker, D., Denham, M.C., Hone, J. and Pagel, M. (2005) On the Regulation of Populations of Mammals, Birds, Fish, and Insects. Science, 22, 607-610. http://dx.doi.org/10.1126/science.1110760
Brook, B.W. and Bradshaw, C.J.A. (2006) Strength of Evidence for Density Dependence in Abundance Time Series of 1198 Species. Ecology, 87, 1445-1451. http://dx.doi.org/10.1890/0012-9658(2006)87[1445:SOEFDD]2.0.CO;2
Birch, L.C. and Browning, T.O. (1995) Herbert George Andrewartha 1907-1992. Australian Academic of Society. http://www.sciencearchive.org.au/fellows/memoirs/andrewartha.html
Sakuramoto, K. (2014) A Common Concept of Population Dynamics Applicable to Both Thrips Imaginis (Thysanoptera) and the Pacific Stock of the Japanese Sardine (Sardinops melanostictus). Fisheries and Aquaculture Journal, 4, 140-151.
Maelezer, D.A. (1970) The Regression of log Ni+1 on log Ni as a Test of Density Dependence: An Exercise with Computer-Constructed Density-Dependent Populations. Ecology, 51, 810-822. http://dx.doi.org/10.2307/1933973
Kuno, E. (1971) Sampling Error as a Misleading Artifact in “Key Factor Analysis”. Research Population Ecology, 13, 28-45. http://dx.doi.org/10.1007/BF02522011
Ito, Y. (1972) On the Methods for Determining Density-Dependence by Mean of Regression. Oecologia, 10, 347-372. http://dx.doi.org/10.1007/BF00345737
Sakuramoto, K. and Suzuki, N. (2012) Effect of Process and/or Observation Errors on the Stock-Recruitment Curve and the Validity of the Proportional Model as a Stock-Recruitment Relationship. Fisheries Science, 78, 41-45. http://dx.doi.org/10.1007/s12562-011-0438-4
Ricker, W.E. (1954) Stock and Recruitment. Journal of the Fisheries Research Board of Canada, 11, 559-623. http://dx.doi.org/10.1139/f54-039
Beverton, R.J.H. and Holt, S.J. (1957) On the Dynamics of Exploited Fish Populations. Fishery Investigations Series II 19 [1-533], Her Majesty’s Stationery Office, London.
Yatsu, A., Watanabe, T., Ishida, M., Sugisaki, H. and Jacobson, L.D. (2005) Environmental Effects on Recruitment and Productivity of Japanese Sardine Sardinops melanostictus and Chub Mackerel Scomber japonicus with Recommendations for Management. Fisheries Oceanography, 14, 263-278. http://dx.doi.org/10.1111/j.1365-2419.2005.00335.x
Kawabata, J., Honda, S., Watanabe, C., Okamura, H. and Ichinokawa, M. (2014) Stock Assessment and Evaluation for the Pacific Stock of Japanese Sardine (Fiscal Year 2013). In: Marine Stock Fisheries Stock Assessment and Evaluation for Japanese Waters (Fiscal Year 2013/2014), Fisheries Agency and Fisheries Research Agency, Japan, 15-46.
Deming, W.E. (1943) Statistical Adjustment of Data [1-261]. Dover Publication Inc., New York.
Passing, H. and Bablok, W. (1983) New Biometrical Procedure for Testing the Equality of Measurements from Two Different Analytical Methods. Application of Linear Regression Procedures for Method Comparison Studies in Clinical Chemistry, Part I. Journal of Clinical Chemistry& Clinical Biochemistry, 21, 709-720. http://dx.doi.org/10.1515/cclm.1983.21.11.709
Aoki, S. (2009) Parameter of a Regression Line Estimated by Deming Regression Method. http://aoki2.si.gunma-u.ac.jp/R/Deming.html
Aoki, S. (2009) Parameter of a Regression Line Estimated by Passing Bablok Regression Method. http://aoki2.si.gunma-u.ac.jp/R/PassingBablok.html
Ohman, M.D. (2001) Density-Dependent Mortality in an Ocean Copepod Population. Nature, 412, 638-641. http://dx.doi.org/10.1038/35088068
Mayers, R.A. (2001) Stock and Recruitment: Generalizations about Maximum Reproductive Rate, Density Dependence, and Variability Using Meta-Analytic Approaches. ICES Journal of Marine Science, 58, 937-951. http://dx.doi.org/10.1006/jmsc.2001.1109
Imre, I., Grant, J.W.A. and Cunjak, R.A. (2005) Density-Dependent Growth of Young-of-the-Year Atlantic Salmon Salmo salar in Catamaran Brook New Brunswick. Journal of Animal Ecology, 74, 508-516. http://dx.doi.org/10.1111/j.1365-2656.2005.00949.x
Sundstrom, L.F., Kaspersson, R., Naslund, J. and Johnsson, J.I. (2013) Density-Dependent Compensatory Growth in Brawn Trout (Salmo trutta) in Nature. PloS ONE, 8, 1-7. http://dx.doi.org/10.1371/journal.pone.0063287
Sakuramoto, K. (2012) A New Concept of the Stock-Recruitment Relationship for the Japanese Sardine, Sardinops melanostictus. The Open Fisheries Science Journal, 5, 60-69.
Sakuramoto, K. (2005) Does the Ricker or Beverton and Holt Type of Stock-Recruitment Relationship Truly Exist? Fisheries Sciences, 71, 577-592. http://dx.doi.org/10.1111/j.1444-2906.2005.01002.x
Sakuramoto, K. (2013) A Recruitment Forecasting Model for the Pacific Stock of the Japanese Sardine (Sardinops Melanostictus) That Does Not Assume Densi-ty-Dependent Effects. Agricultural Science, 4, 1-8. http://dx.doi.org/10.4236/as.2013.46A001
Sakuramoto, K., Shimoyama, S. and Suzuki, N. (2010) Relation-ships between Environmental Conditions and Fluctuations in the Recruitment of Japanese Sardine Sardinops melanos-tictus in the Northwestern Pacific. Bulletin of Japanese Society of Fisheries and Oceanography, 74, 88-97.
Singh, A.A., Sakuramoto, K. and Suzuki, N. (2014) Model for Stock-Recruitment Dynamics of the Peruvian Anchoveta (Eugraulis ringens) off Peru. Agricultural Sciences, 5, 140-151. http://dx.doi.org/10.4236/as.2014.52017
Watlers, C.J. (1987) Nonstationarity of Population Relationships in Exploited Populations. Canadian Journal of Fishers and Aquatic Sciences, 44, 156-165. http://dx.doi.org/10.1139/f87-319
Zheng, J. and Kruse, G.H. (2003) Stock-Recruitment Relationships for Three Major Alaskan Crab Stocks. Fisheries Research, 65, 103-121. http://dx.doi.org/10.1016/j.fishres.2003.09.010
Sakuramoto, K., Sugiyama, H. and Suzuki, N. (2001) Models for Forecasting Sandfish Catch in the Coastal Waters off Akita Prefecture and the Evaluation of the Effect of a 3-Year Fisheries Closure. Fisheries Sciences, 67, 203-213. http://dx.doi.org/10.1046/j.1444-2906.2001.00241.x