Smalma, interesting observations about recent Skagit steelhead returns. After some discussions with Kate her thoughts are that age structure is related to ocean conditions. Russian biologists believe that repeat spawner rate is related to relative freshwater productivity and she tends to agree. The recent age structure being similar to that of the 1970s probably doesn't mean they are finding better ocean conditions, more likely poorer conditions and more competition from pinks and hatchery steelhead. Because time of return is in part determined by growth in the salt, in poor growth conditions it might take an extra year for many of the fish to reach the stage of return. The extra year in the ocean also mean higher mortality. In the 1970s steelhead populations were much higher and the fish would have been competing with each other for food so one might expect more 3 salt fish in the return. The dramatic change in ocean conditions in the early 80s and freshwater habitat losses reduced the population of steelhead and at the same time pink and chum populations were lower. It might have been the case that low populations meant less competition for food so that even though ocean conditions were not good a higher portion of the steelhead matured after two years in the salt. In recent years pink populations, particularly Russian pinks, which compete with steelhead have been high. In addition hatchery steelhead which compete with wild fish, at least for the first year in the salt if not longer, are being released at high numbers. The change in the age ratio might mean Skagit fish are finding better ocean conditions but more likely it is the opposite case.

One can make similar arguments about the freshwater life history stages and relative productivity to explain the repeat spawner rates. In both cases to know what is happening requires more ocean research and that is not happening now and probably not for some time in the future.

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