Week of March 6, 2023

Breaking News:  Sudden Change of Daily Activities

This week start­ed out fair­ly hec­tic as we learned on Tues­day, March 8 that the Sut­ter Bypass was expect­ed the run again start­ing late-Fri­day night, March 10.  Begin­ning March 8, this ini­ti­at­ed a flur­ry of activ­i­ty to pri­or­i­tize field drain­ing and removal of caged fish to relo­cate them to the UC Davis Lab for JSATS (teleme­try) tag­ging there instead of out at the project field as orig­i­nal­ly planned.  More details on this in the Activ­i­ty Updates sec­tion below.

Updated Catch Numbers

As of March 9, we had cap­tured over 425 fish via trap net and sein­ing. Based on size chart assess­ments, these include 116 wild fall run-sized, 1 late-fall run-sized, 10 win­ter run-sized, and 38 spring run-sized Chi­nook salmon.  On March 10 (the date of this email), many more wild fish were count­ed but I do not have these num­bers to report out at this time.  Over­all mor­tal­i­ty has been low.  About 3.1% (13/425) mor­tal­i­ty of all fish encoun­tered so far with fyke and seine. All of these were dead when we encoun­tered them, no fish have died dur­ing or short­ly after our han­dling that we have seen. Of these, 5 were PIT-tagged hatch­ery fall-run salmon, 4 wild fall run salmon, 1 shad, 2 mos­qui­to fish, 1 sun­fish.

What is notable about these num­bers is the sud­den increase in the spring run-sized salmon count which increased by 31 upon the first fyke check after ini­ti­a­tion of drainage on March 9.  This is a very inter­est­ing result, and the UC Davis Field­work Leader offered the fol­low­ing thoughts on this:  Intu­ition says that the 31 “spring run sized” salmon are actu­al­ly fall run fish which are larg­er than expect­ed due to flood­plain rear­ing.  Reminder:  All wild fish col­lect­ed are also genet­i­cal­ly test­ed for final con­fir­ma­tion of run clas­si­fi­ca­tion and final account­ing will be adjust­ed accord­ing­ly after this analy­sis is com­plet­ed.

General In-field Activity Updates

As men­tioned, tremen­dous effort began the morn­ing of March 8 to get all the caged fish out and off to the lab.  This was done in a sin­gle day with a full con­tin­gent of the UC Davis Team plus some extra help pro­vid­ed by “vol­un­teer” rice grow­ers and their equip­ment to help get the job done as quick­ly as pos­si­ble.  It was essen­tial­ly a buck­et brigade out there to tedious­ly get all the fish out using buck­ets, fish nets, ice chests and ATV’s.  Sev­er­al pho­tos attached help to tell the sto­ry.  In addi­tion, the bot­tom drain was adjust­ed to allow a max­i­mum amount of water to exit the field while also main­tain­ing the fyke net.  All went well and by the end of the next day (March 9) the top check was near­ly com­plete­ly dewa­tered and searched for any strand­ing of salmon (which is not expect­ed based upon pre­vi­ous obser­va­tions).  Only one dead fish was found and it was a large­mouth bass.

General Lab Activity Updates

Ear­ly in the week, the UC Davis Team did all the JSATS-tag­ging of 350 lab-reared salmon.  The UC Davis Team had begun the process of JSATS-tag­ging the rice-reared fish in the lab.  As of the end of March 9, about 190 of these fish had been tagged.

Looking Out

We were obvi­ous­ly hop­ing the Tis­dale Weir over­top­ping event might be milder than pro­ject­ed. We tried to beat the clock to count as many nat­ur­al-ori­gin and PIT-tagged salmon remain­ing in the field as pos­si­ble to fin­ish off what has been a fair­ly good field sea­son except for the impacts of the slow­er fish growth result­ing from the recent unsea­son­ably cool weath­er.  Still, the UC Davis Team was com­mit­ted to get­ting as much count­ing done as pos­si­ble until the field became recon­nect­ed with the sec­ond round of bypass flood­wa­ter flows.  Ulti­mate­ly, flood­wa­ters began to over­take the field by the after­noon of Sat­ur­day, March 11 leav­ing num­ber of both our PIT-tagged and nat­ur­al-ori­gin salmon left uncount­ed.  

Grower’s Argo and employee deployed in a pinch to help get caged fish collected quickly.
Grower’s Argo and employ­ee deployed in a pinch to help get caged fish col­lect­ed quick­ly.
Cage being hauled from inside the field to the field edge where the fish will be extract­ed
Member of the UC Davis Team and a grower’s employee working to remove salmon from a cage while in the field.
Mem­ber of the UC Davis Team and a grower’s employ­ee work­ing to remove salmon from a cage while in the field.
Anne Boyd of the UC Davis Team explain­ing cur­rent field activ­i­ty and plans for the fish head­ed to the lab for tag­ging
The tank used for transporting the rice field salmon to the lab for tagging.
The tank used for trans­port­ing the rice field salmon to the lab for tag­ging.
Fish tak­en from a cages being trans­ferred into an ice chest onto the ATV
UC Davis field tech bringing another cage from the field.
UC Davis field tech bring­ing anoth­er cage from the field.
Video of fish being tak­en from the cages and into an ice chest so they can be put into the hold­ing tank at the field edge
An empty cage being carried to the edge of the field
An emp­ty cage being car­ried to the edge of the field
Peter Aron­son of the UC Davis Team talks about tag­ging plans for the salmon being removed from the field
The Argo, with a load of fish, head­ing for the hold­ing tank
A cage being opened up for the removal and transport of salmon.
A cage being opened up for the removal and trans­port of salmon.
Bring­ing a cage full of fish to the field edge with the sounds of a big grind of geese over­head
Haul­ing anoth­er cage from the field
Using a fish net to remove salmon from the cage in the field
The project rice farmers’ lab, Opie, sad yet again because he can’t come out and play with the field crew
The project rice farm­ers’ lab, Opie, sad yet again because he can’t come out and play with the field crew
Argo climbs out of the field with anoth­er load of salmon to deliv­er to the hold­ing tank
Der­rick Alcott, UC Davis Lead Researcher, adjust­ing the drain box to max­i­mize out­flow to the bypass chan­nel
Photo of the drainage canal and fyke next operating at maximum outflow from the field
Pho­to of the drainage canal and fyke next oper­at­ing at max­i­mum out­flow from the field
Video of the drainage canal flow­ing through the fyke net
Video of the low­er por­tion of the drainage canal to where it dumps into the bypass canal.
The bypass channel where the rice field salmon enter to continue their journey to the ocean
The bypass chan­nel where the rice field salmon enter to con­tin­ue their jour­ney to the ocean
The top check of the project rice field nearly drained
The top check of the project rice field near­ly drained
The top check of the project rice field almost completely drained
The top check of the project rice field almost com­plete­ly drained
All of the caged fish reared on the rice field safe­ly removed from their cages and head­ed back to the UC Davis lab for acoustic teleme­try tag­ging
Der­rick Alcott of the UC Davis Team explains tag­ging activ­i­ty live from the UC Davis Lab
Picture of fish tagging surgery. (Photo by Brian Baer)
Pic­ture of fish tag­ging surgery. (Pho­to by Bri­an Baer)
Fish weighed and placed on table for surgery
Close-up photo of a JSATS tag being inserted during a surgical procedure. (Photo by Brian Baer)
Close-up pho­to of a JSATS tag being insert­ed dur­ing a sur­gi­cal pro­ce­dure. (Pho­to by Bri­an Baer)
Oper­a­tion of a Pinger Dish, a device for test­ing and record­ing data from a JSATS Tag
Video of the sur­gi­cal process to insert a JSATS tag into a fish
Video of the UC Davis crew pro­cess­ing a wild salmon from the exit­ing the project field. This involves mea­sur­ing the fish and tak­ing a very small fin clip for lat­er genet­ic analy­sis to con­firm the run of the salmon being record­ed in the catch data se
Close-up photo of cutting the fin clip for later genetic testing to confirm the run of the salmon being recorded in the catch data set.
Close-up pho­to of cut­ting the fin clip for lat­er genet­ic test­ing to con­firm the run of the salmon being record­ed in the catch data set.
Video of the UC Davis crew pro­cess­ing a lab-reared, PIT-tagged salmon placed into the field sev­er­al weeks ago and now exit­ing the project field. This involves mea­sur­ing and weigh­ing the fish record­ed in the catch data set
The type of scale used to weigh each lab-reared, PIT-tagged salmon. The container with water is placed on the scale and set to zero. Then, the fish is placed into the container and weighed. The instrument is so sensitive that it is weighed in the box with the lid closed
The type of scale used to weigh each lab-reared, PIT-tagged salmon. The con­tain­er with water is placed on the scale and set to zero. Then, the fish is placed into the con­tain­er and weighed. The instru­ment is so sen­si­tive that it is weighed in the box with the lid closed

Other Field News

Update on the 2022–23 Salmon Project Fieldwork Season

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team unloading salmon release equipment from truck trailer at the river

Week of March 13, 2023

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Alexandra Wampler gathering salmon for fin clipping.

Week of February 27, 2023

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