The following Tacoma Public Utility site has graphs showing 2017 returns for various hatchery and natural origin fish.
https://www.mytpu.org/file_viewer.aspx?id=65889It is interesting that most natural origin species had returns comparable to the ten year average while all hatchery origin species except springers had a dismal year compared to the ten year average. Two reasons jump out but there could be others. One is that the hatchery release has been cut substantially and the other is that natural origin fish survive difficult ocean conditions better than hatchery fish. Does anyone have a good answer for the discrepancy in returns?
If the later reason is valid it has implications for the legislator and a number of fishermen who advocate ignoring HSRG (and potential ESA listings) and turning Puget Sound and Willapa bay into hatchery fish farms.
These are just graphs of 2017 counts relative to a 10 year average. They don't tell you anything about the numbers of fish released to get those returns. These are only good for one thing - TPU gauging whether or not they are meeting their adult mitigation obligation.
Survival varies annually as do hatchery release number (sometimes only slightly, sometimes hugely...as given in the example of summer sthd)
The least informative of these numbers is the wild fish at the trap. Raw numbers will not inform whether hatchery and wild fish are performing the same, better, or worse - you need rate of return/unit released to do that.
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