Summary from Anna Sturrock

  1. Many species of Pacific salmon due to dynamic shifting environments
  2. Central Valley salmon the ‘world leaders’ in salmon diversity…juvenile or adult going in or out of the Sacramento River every day of the year
  3. Status of world leader in diversity at risk.  Winter run are endangered, spring run is threatened, fall run are a species of concern (not immune to collapse)
  4. Collapse of fall run fish in 2009, 2010
  5. Why? Perhaps an erosion of diversity in life history.
  6. An  imbalance with water supply vs. demand.  Less in the south but more demand. Solution was some serious engineering of levees and canals
  7. When and how much rain comes is highly variable! And if it falls more as rain than snow in the mountains then it has consequences for amount of water over the summer
  8. 25 million residents rely on Delta water
  9. The Delta has been transformed from a diverse habitat complex to a stable homogenous area where habitats are disconnected and greatly disrupted
  10. San Joaquin listed as most endangered river as listed by American Rivers (environmental NGO) in 2014
  11. Amount of freshwater strongly correlated with adult returns…the wetter the better
  12. Other major solution to problems was perceived to be hatcheries
  13. Survival so poor of fish moving through the Delta that a solution was to truck the fish from the hatchery
  14. Otolith microchemistry a useful tool for reconstructing a fish’s life history
  15. By reconstructing size of the fish that had survived we can see that being larger going to sea is not always better

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