/ 



LIFE HISTORY OF THE LAKE HERRING (LEUCICHTHYS 

 ARTEDI LE SUEUR) OF LAKE HURON AS REVEALED BY 

 ITS SCALES, WITH A CRITIQUE OF THE SCALE METHOD 



By JOHN VAN OOSTEN, Ph. D. 

 Assodale Aquatic Biologist, U. S. Bureau of Fisheries 



CONTENTS 



Page 



Introduction 267 



The problem 267 



Material 268 



Acknowledgments 269 



General considerations 270 



Description of coregonid scales 270 



Typical scales 270 



Irregularities in scale structure 271 



Scale method and its application 272 



Methods of measurements and counts 272 



Body measurements 272 



Scale measurements and counts 274 



General historical review 276 



PART I 



Critique of scale theory and method 278 



Assumptions of the method 278 



Identity of scales throughout life 279 



Constancy in number of scales throvighout life 279 



Annuli and number of years of life 287 



Criticisms 288 



Indirect evidences 292 



Direct or experimental evidences 293 



Correlation between growth of body and scale 301 



Historical 30 1 



Differential growth of scales of a lake herring and of the areas of one of its scales.. 310 



Age variations in the growth of the head 312 



Age variations in body scale (K/V) ratios based on selected (X) and unselected 



(non-X) scales of adult lake herring 313 



Age variations in body scale (K/V) ratios of juvenile coregonids 316 



Average length of body and scale compared for corresponding years 321 



Comparison of computed lengths based on anterior radii and on diameters of herring scales. _ 322 

 Factors involved in apparent discrepancies of length computations based on the scales of 



herring 328 



Time of formation of an annulus and factors involved in it 344 



265 



