SF Chronicle – Fallow, flooded rice fields just the thing for salmon fry. What is that delicacy… Nigiri?

    Good news is not always news, not as a news reporter defines it. This morning a story ran in the local press declaring that there is at least one win-win response to California's on-going rain shortage, now in its 15th month, and evermore heated argument over water system priorities among proponents of wildlife, crops, and urban faucets. It reports a rare alignment in what's best for one of the state's most iconic finned friends and for farmers – specifically, those who grow the California food crop that consumes the most irrigation water.

    This piece is well worth reading even though, as explained further along, it has a few holes.

    The gist is that for the last few years a rice farm out in the Central Valley, west of Sacramento, has been growing whopper Chinook salmon fry. The farm is on the Yolo Bypass, a vital part of the state's water and flood control system. It is a stretch of about 60,000 acres in all that are part of the ancient, now mostly diked-off flood plains of the Sacramento and other rivers streaming in from the north and east. But for many years state authorities have allowed the bypass to flood in winters when the rivers run high . This eases threats to the state capital and many other communities (Here is a Wiki pic of the watery Yolo with Sacramento in the distance). As has long been appreciated, the wintry expanse also has been a boon for migrating waterfowl. After it drains off, farmers move in.

   A UC Davis team of researchers got a bright idea. It, working with the California Trout conservation organization and the state's dept. of water resources, have sown thousands of  juvenile salmon in the shallow waters during years – about two thirds of them – that the farmland inundates. Bingo, the little guys grow far faster – up to five times – than do their cohorts in what are left of natural flood plains. Turns out a fallow, flooded rice field is Eden for a growing little salmon as long as one digs a few trenches to shelter them from hungry wading birds. Not only that, but after the acreage drains and takes its load of well-fed Chinook youngsters into the main riverbeds in spring, many more of them survive the trip down to the sea and the migration back to spawn. By one measure, 60 percent return compared to 5% or fewer for typical Chinook grounds elsewhere.

   So, one can learn something useful from this story and also get a warm feeling that some water deals can make erstwhile rival parties – farmers and wildlife advocates in this case – happier.

   Fimrite wrote this with a strong style. I for one learned a lot and found it cheering to boot.


   To start with a near-trivial omission, the story only names the experiment. It is the Nigiri Project. I put a picture of nigiri at the top. It is common in sushi restaurants – a slice of fish, often smoked salmon, on a bed of rice. The metaphoric name is beyond good, it is great. Perhaps in this foodie-paradise that is the Bay Area everybody knows that? I didn't. Whether Fimrite omitted  the name's etiology or his Chronicle editors cut it out I don't know. Its absence cuts a big slice from the story's delight.

   Second, what about the operator of the ranch? Are the owners happy with this development? (answer: yes, but the story should have said so explicitly with credit to somebody in charge there). Any impact at all on the ability to farm the land during the dry season? Third, does this technique have potential application in other rice growing regions of the state – when do the farmers there flood there lands and for how long and could they similarly expand salmon spawning and juvenile sheltering grounds without sacrificing any of their main aim of growng a lot of rice? Fourth, what will happen to returning and gamete-laden Chinook if they show up in a winter when the Yolo does not flood? Might they set up housekeeping in other shallows or just die in frustration? Fifth, these tests use hatchery salmon fry. Are wild salmon already using the bypass in significant numbers to spawn or at least do their hatchlings already go there to fatten up? Would mixing in a lot more hatchery fry harm remaining stocks of purely native, wild salmon?

   That's a lot. The news hole is small at the shrunken Chronicle. One cannot expect encyclopedic coverage. But to not explain nigiri? Baffling. 

  Finally, this is not news. It remains smart for the Chron to include it in continuing coverage of the drought from many angles. But it is no exclusive. Even The Chronicle itself has written it up before.

   Other stories:

  Grist for the Mill: UC Davis News Press Release; UC Davis Study Text ;

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