Sprat from Norwegian Waters - An Analysis of Vertebrae Counts

Abstract

The present report gives a review of some results of the vertebrae counts of sprat from the years 1927-1949. Within each sample of sprat of the 0-group there is generally a positive correlation between the size of the fish and the number of vertebrae. The positive differences between the average number of vertebrae of "large" and "small" fish of the same sample is generally smaller than 0.40. It has been shown that samples taken at the same locality within a short space of time may differ significantly as to the frequency distribution for number of vertebrae. It is therefore difficult to obtain representative samples from a certain locality. For this reason a comparison with respect to number of vertebrae of sprat from diffelrent year classes, and from different waters, may be of doubtful value. Our samples can not be considered representative of more than the shoals from which they have been taken. In each year there may be significant differences between the samples as to the average number of vertebrae, indicating that the shoals from which they have been taken are of somewhat different origin.