Fecundity is an important parameter used in the calculation of Atlantic salmon egg depositions for rivers in the Newfoundland Region. It is usually derived from ovaries collected in the recreational fishery during summer. The process involved in fecundity determinations is time consuming and expensive. From this perspective, it would be desirable to know the extent on inter-annual and inter-river variability in fecundity and the risk involved in using default values as a means of reducing cost. Annual fecundity data were available for one river in Labrador and nine rivers in insular Newfoundland. Most rivers showed significant annual variability in relative fecundity expressed in terms of weight (egg/kg) and length (eggs/cm) and there were significant differences among rivers as well. There was also a suggestion that there are regional differences in fecundity, for instance between northeast coast rivers and south coast rivers. Fecundity for repeat spawning grilse tended to be higher than for virgin grilse and significantly so for some rivers. Given the magnitude of differences observed within and among rivers, in order to minimize the risk of error in the calculation of egg depositions, the use of defaults should be avoided.
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