Thread by @jarosenfield

Thing I’ve been hearing a lot recently: “Real Time Fish monitoring should dictate when the CVP & SWP export pumps are turned off to protect #endangeredspecies. See fish-pump off...no fish-pump on”.

There is *so* much wrong with this, it will require a #thread to unpack.

2a) Real time monitoring is not individual surveillance. Ecological monitoring will always miss individuals, esp. for rare species. (ie, we call it “sampling” & use statistics).

Monitoring will likely miss rare species & the early/late migrants that populations depend on.

2b) This point — the need to maintain life history diversity to prevent declines — can’t be overstated. Just protecting a narrow slice of these species’ diversity is a recipe for further decline & loss of resilience.

journals.plos.org/plosone/articl…

1) The CVP & SWP export pumps were never “turned off” to protect #endangeredspecies in water years 2010-2018. (& not 2019 either)

escholarship.org/uc/jmie_sfews
Fig 4 shows how often exports were limited (slowed) by different constraints, but only maintenance caused complete shut down.

2c) Salvage of Delta smelt at the export pumps has occured several times on the same days when nearby real-time monitoring did not detect Delta smelt.

Again, we are not capable of tracking the location of all fish as they move through the Delta.

3) The CVP and SWP export pumps cannot be switched “on” and “off” at a moment’s notice. They are massive pumps that reverse river flows, not countertop blenders.

The “flexibility” exporters talk about is not a feature of their infrastructure or of their water demand pattern.

4) Exports have a large effect on Delta habitats & reservoir releases are often timed to correspond with pumping schedules, so the effect of the pumps lingers even after exports are ramped down. Adjusting exports only after we detect fish is often too late to avoid impacts.

5) Advocates of this impractical/impossible approach to “fine tune” exports to avoid harming #endangeredspecies often also call for “ecosystem management”.

But the “see fish, pumps off; no fish pump, on” approach is the opposite of ecosystem management.

6) *SFBay hosts 6 #endangered fish species which are harmed by unsustainable 💦 diversions

*2008/09 #EndangeredSpeciesAct protections for these fish were based in the best science

*new science shows they need stronger protection
nrdc.org/experts/doug-o…

nrdc.org/experts/doug-o…

7) Whittling down protections for #endangeredspecies under the guise of “flexibility” & “real time data” is not a solution, it’s a recipe for #extinction.

Solutions require acknowledging that the #SFEstuary ecosystem and its fishes need more help & then following the #science.