Juvenile spring Chinook parr and smolt mortality.

<p>Juvenile juvenile spring Chinook parr or smolts were fed for 23 d with pellets, salmon eggs (- control), or salmon eggs cured with 1 of 4 or 5 commercially available cures. Bars represent the mean % mortality for three replicate tanks (N = 55 fish per tank). A value of 0 represents treatments that had no mortality in all three tanks. NT = Not Tested. *Significantly different from the group fed pellets (<i>P</i><0.05).</p

Index of cumulative mortality in juvenile Chinook and steelhead parr and smolts.

<p>Juvenile Chinook and steelhead parr and smolts were fed cured eggs for a period of 23 d. We calculated cumulative mortality by summing the number of fish that died each day for all treatment groups (calculated separately for each lifestage and species) fed cured eggs and dividing this by the total number of fish that died during the 23 d period.</p

Relationship between the number of eggs consumed and the time to mortality.

<p>Survival time of juvenile spring Chinook fed the equivalent of 3 (low), 6 (medium), or 10 (high) eggs that were cured with cure 5 (A) or cure 4 (B). The cured egg mixture was administered into the stomach daily using a syringe. Control fish were given uncured eggs. The experiment was terminated after 10 d. Each group consisted of 20 fish.</p

Effect of pre-soaking the cured eggs on the mortality of juvenile Chinook salmon.

<p>Eggs cured with cure 1 were soaked for 0 s, 30 s, 60 s, or 10 min prior to feeding. Each bar represents the % mortality in an individual tank (N = 30 fish per tank).</p

Description of experimental methods.

<p>Experimental description refers to the section number in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0021406#s2" target="_blank">methods</a> section. CHS: Spring Chinook, ST: Steelhead.</p

Effect of sodium sulfite on mortality in juvenile spring Chinook.

<p>The fish were fed (10 d, 1.5% BW/d) eggs that were cured with the full cure (FC), the same cure without sodium sulfite (-Na sulfite), or the same cure without sodium sulfite or sodium nitrite (-Na sulfite -Na nitrite). We evaluated the effect in two cures (cure 1 and 5), however cure 5 does not contain sodium nitrite. Each bar represents the mean % mortality in 2 (cure 1) or 3 (cure 5) replicate tanks (N = 30 fish/tank). 0 represents no mortality in a tank. Groups sharing a line above the bar are significantly different (<i>P</i><0.05).</p

Passage dates for Yukon River Chinook salmon radio tagged during the peak of the run and tracked upriver during 2003.

<p>Distances of the upriver locations from Russian Mission, number of fish, and numbers of days taken by the group of tagged fish to pass the sites are presented. The reduced sample size at the upriver locations reflects the harvest of radio-tagged fish in mainstem fisheries and the movement of fish into other terminal tributaries along the migratory route.</p><p>¹Includes several fish tagged during the pulse, but moving substantially later past the site.</p><p>Passage dates for Yukon River Chinook salmon radio tagged during the peak of the run and tracked upriver during 2003.</p

Relationship between movement rates and nonmetric multidimensional scaling (NMS) ordination scores for 96 Yukon River Chinook salmon returning to the Salcha River during 2002–2004.

<p>Both the Axis 1 (left panel) and Axis 2 (right panel) scores and associated regression lines are presented for the five sequential tracking stations located along the migratory route.</p

Yukon River Chinook salmon stocks analyzed using within-stock ordination to describe the migration patterns of individual fish returning to terminal tributaries based on average movement rates (km d^-1) in sequential reaches of the basin.

<p>Pearson’s <i>r</i>² values represent the proportion of the multivariate data explained by the synthetic variables (axes).</p><p>Yukon River Chinook salmon stocks analyzed using within-stock ordination to describe the migration patterns of individual fish returning to terminal tributaries based on average movement rates (km d^-1) in sequential reaches of the basin.</p

Movement rates for the principal Chinook salmon stocks returning to regional areas of the Yukon River basin during 2002–2004.

<p>Estimates and standard error are based on fish with complete tracking records (recorded by all stations passed). Capitalized stock names indicate major stocks within the basin.</p