 Opportunistic sampling to estimate fecundity of chum and coho salmon from Norton Sound. Introduction: This project is designed estimate the fecundity (the number of eggs) of chum and coho salmon from Norton Sound. Issues Addressed: The recent decline of adult salmon abundance in numerous Norton Sound tributaries has caused concern that chum salmon production may be affected by their reproductive capacity and subsequent seeding of the spawning grounds. Fecundity estimates are essential for determining the reproductive capacity and spawning ground seeding rates of salmon populations, yet there is still relatively little knowledge of Norton Sound salmon fecundities. This project will sample multiple fisheries (subsistence and test fisheries) in Norton Sound to estimate fecundities in specific populations. Chum salmon will be the target species while the methods are refined, after which all species will be targeted whenever the season and budget allows. While only one river in the Norton Sound has been examined to date, we plan to target another system this summer.  Results
to Date: In the summer of 2002, over a
hundred of both female chum and coho
salmon were retained by ADF&G technicians
working on the Unalakleet Test Net
project. The salmon were measured, scale
samples taken, and their ovaries retained
and preserved for later analysis to
estimate their fecundity. The eggs were
shipped to the NSEDC Anchorage office
where they were all subsampled for
estimates. The results have been rather
surprising, indicating that Unalakleet
River coho have higher fecundities (mean =
5334) than any other population found in a
well-known review (Sandercock, 1991). It
was also determined that Unalakleet River
chums have a higher relative fecundity
(number of eggs per cm length of the fish,
a common measure of fecundity) than other
stocks in a review by Salo (1991), with a
mean fecundity = 2809.
For further information please contact
Simon Kinneen.
Norton Sound Economic Development Corporation
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