SAMPLE SIZE IN THE STUDIES OF POPULATION AGE STRUCTURE OF SOME FISH SPECIES
The Stanisław Sakowicz Inland Fisheries Institute in Olsztyn
ABSTRACT. Minimum size of a representative sample collected for age structure analysis of fish populations: roach, bream, tench, whitefish, and pike ranges from 150 to 300 individuals. In case of stratified samples it is about 200, and for random samples –250 individuals on the average. Due to more laborious collection of stratified samples, for age structure analysis random samples are more appropriate. They are also representative for size structure analysis.
Key words: SAMPLE, POPULATION, AGE STRUCTURE, RANDOM SAMPLING