Salmon Tracker: Where are California’s Chinook now?
Spring is well underway which means movement and change is evident everywhere one looks. The lengthening daylight is stirring everything to life. Waterfowl are lifting and heading to northern breeding grounds along with many shorebirds and songbirds. And, in streams, last year’s cohort of juvenile salmon (including winter, spring, and fall/late-fall Chinook salmon and steelhead) have hatched and been rearing and feeding on aquatic insects and other invertebrates whose life cycles and production are boosted by increasing daylight and nutrients flushed in during winter’s overbank flows from riparian zones and on floodplains and flowing in with the rising runoff of snowmelt-driven tributaries.
Fall-run salmon fry that reared near the spawning grounds all winter are to transforming into silvery smolts, readying themselves for their downstream migration and transition to life in the ocean. Last summer’s winter-run juveniles and the past fall-run fry that moved downstream with the high and flooding river flows this past winter were able to take advantage of inundated riparian zones and floodplains that provide refuge from the river torrents and expanded rearing opportunities afforded by access to these ecologically important areas. Both upstream and downstream rearing groups of salmon will make their final push to the ocean over the next couple of months, when by June, ocean productivity will be peaking to welcome them to the greatest smorgasbord of their lives.
I am sure it is not lost on anyone the good fortune of this winter’s abundant water for the salmon runs, especially in light of the very low numbers of natural spawners of all the salmon runs this past season, providing the best possible conditions for the progeny of these depressed salmon runs to get a good start, which we are all working to ensure experience the best survival possible to contribute to recovery of our Sacramento River salmon runs.
- Keith Marine, Principal Fisheries Scientist, Aquatic Resources Consulting Sciences
