AGE OF A FISH
THE WAY TO TELL IT. Could y 7 ou tell the age of a fish if asked to do so? It has been found that the age of a fish may be read from its scales. These increase in size by annular growths, two rings being formed each year. The “ otoliths,” or ear stones, wliiph lie in two sacs on either side of the base of the cranial cavity, afford another means of determination. Like the scales, the otoliths increase bytwo rings annually Each spring a white ring is formed, and each autumn a black one. Thus the number of either white or black rings in an otolith gives the age of the fish in years. In the case of flatfish the latter method has been found more reliable, whereas in the case ot the cod the scales give a better result. Although varying much in size and shape in different species, the otoliths show ‘a remarkable constancy in the same sjoecies; hence they are of considerable value in tho diagnosis of a species.
Permanent link to this item
https://paperspast.natlib.govt.nz/newspapers/OW19230724.2.177
Bibliographic details
Otago Witness, Issue 3619, 24 July 1923, Page 41
Word Count
178AGE OF A FISH Otago Witness, Issue 3619, 24 July 1923, Page 41
Using This Item
Allied Press Ltd is the copyright owner for the Otago Witness. You can reproduce in-copyright material from this newspaper for non-commercial use under a Creative Commons New Zealand BY-NC-SA licence. This newspaper is not available for commercial use without the consent of Allied Press Ltd. For advice on reproduction of out-of-copyright material from this newspaper, please refer to the Copyright guide.
Log in