vi CONTENTS 



POPULATION DYNAMICS AND EXPLOITATION OF SEALS IN THE EASTERN 

 CANADIAN ARCTIC. 



I. A. McLaren, Fisheries Research Board of Canada, Arctic Unit and 

 Department of Zoology, Yak University i68 



DISCUSSION 184 



THEORETICAL AND MATHEMATICAL MODELS OF 

 EXPLOITED POPULATIONS 



THE CONCEPTUAL FORMULATION AND MATHEMATICAL SOLUTION OF 

 PRACTICAL PROBLEMS IN POPULATION INPUT-OUTPUT DYNAMICS. 



K. E. F. Watt, Statistical Research & Services, Canada Department 



of Agriculture, Ottawa ........ 191 



THE APPLICATION OF MATHEMATICAL MODELS TO FISH POPULATIONS. 



J. A. GuUand, Fisheries Laboratory, Lowestoft .... 204 

 DISCUSSION . . . . 218 



SOME EXPERIMENTAL AND THEORETICAL APPROACHES 



PREDATION AND EFFICIENCY IN LABORATORY POPULATIONS. 



L. B. Slobodkin, Department of Zoology, University of Michigan . 223 



LONG-TERM DYNAMICS OF CERTAIN NORTH SEA HSH POPULATIONS. 



R. J. H. Beverton, Fisheries Laboratory, Lowestoft . . . . 242 



DISCUSSION 260 



ON SOME ADAPTATIONS TO THE REGULATION OF POPULATION DENSITY 

 IN HSH SPECIES WITH DIFFERENT TYPES OF STOCK STRUCTURE. 



G. V. Nikol'skii, Biology & Soils Faculty, Moscow State University 



and Institute of Animal Morphology, U.S.S.R. Academy of Sciences 265 



THE EFHCIENCY OF REPRODUCTION AND RECRUITMENT IN FRESHWATER 

 HSH. 



E.D.LeCrcn, Freshwater Biological Association, Ambleside. . . 283 



DISCUSSION 297 



PREDATION AND COMPETITION IN RELATION TO 

 EXPLOITATION 



THE EFFECT OF SEAL STOCKS IN RELATION TO SCOTTISH MARINE 

 nSHERLES. 



B. B. Kzc, Marine Laboratory, Aberdeen 305 



SEALS AND SALMON NETS. 



W. M. Shezrei, Freshii^ater Fisheries Laboratory, Pitlochry . .312 



GREY SEALS AS COMPETITORS WITH MAN FOR SALMON. 



J.D.Lockie, The Nature Conservancy, Edinburgh . . -3^6 



