Project field is fully contained with a much lower volume of water leaving the field only through the modified board with a hole/notch. Therefore, the rate of exit of fish from the field has reduced to about 1–3 fish per day. However, the science team continues counting and releasing fish daily. We have counted about 50 salmon thus far. Based on salmon size-class assessment, we suspect we have counted mostly Fall run (about 40), 1 late-Fall run, 7 Winter run and 2 Spring run during seining and fyke net trap operations. We have also observed splittail, shad, and hatchery steelhead within the study fields. Occasional predators include bass and sunfish, and larger predators are being sampled for diet contents via gastric lavage and released.
The UCD Team successfully PIT-tagged nearly 4,500 lab-reared salmon and deployed all of the fish cages (to grow JSATS-taggable fish) into the field. The release of free-swimming and caged fish has begun. In addition, 100 of our 200 Late-Fall yearlings have been double-tagged with PIT and JSATS and were also released into the field. We are now monitoring movements of these individuals through the seven PIT-wired boxes.
Both the bypass and dryside fields continue to be monitored, in real-time, with autonomous HOBO data loggers and will remain so until end of the field season, or another flood approaches, at which point the real time system from the bypass field would be retrieved.
The grower continues to refine irrigation timing and assess the benefits of trying out the two holes in the upper boxes. We believe this adjustment being tried this year (used all single-hole boards last year) will help to equalize flow and enable the grower to better maintain desired flood depths of 10–12 inches in each check.
Steve Neader, the Rice Grower currently working with the project team, adjusting one of the special boards used for the Ricelands Salmon Project.The fyke net positioned at the outfall drain of the project field.The Team uses a seine to push fish towards the fyke net for counting and recording the salmon.UCD Team discusses the right approach to deploy the seine in the field.The UC Research Team preparing to walk out into the field to seine for salmon.The Team carefully takes the gathered seine out towards the open water.The UC Davis field crew heading out for more work in the trenches.Another shipment of fish cages arrive.Fish cage being secured in the field with anchoring stake.Fish cage being installed and secured in place ahead of lab-reared salmon being placed inside.Derrick Alcott, Lead Project Researcher, discussing how seining is used for the project.One of many cages brought out into the field for installation.The seine being brought in from the field with fish for counting.A rice box, maintaining target depth of 10–12” and providing fish passage into next rice check through 2” holes.Work being done to set up a PIT-tag receiver station at one of the rice boxes providing fish passage.Landscape image showing flood status of our project field compared other fields in the bypass. Helps to illustrate the fish habitat “extension” of this pilot management practice.UC Davis Team placing lab-reared salmon into protective cages. (Photo by Peter Aronson)UC Davis Team releasing the first 100 of the 200 late-Fall Run Yearlings into the top check of the Project field.Lab-reared, PIT-tagged salmon being released into the project field. (Photo by Peter Aronson)Trailer with aerated tank used to transport and deliver salmon from the UC Davis lab to the project field. (Photo by Peter Aronson)Short video of the late-Fall Run Yearlings on the day of release.
