Conference Call

October 09, 2019 Slides

By phone:

Cyril Michel, Susan Strachan, Cesar Blanco, JD Wikert, Mike Urkov, Mark Gard, Mark Tomkins, John Kelly, Bruce McLaughlin, Mike Berry, Carl Dealy, Tricia Bratcher, Matt Brown, Towns Burgess, Jason Hassrick, Mike Wright, John McManus, Rod Wittler, Sadie Gill, Jim Peterson, Adam Duarte, Priscilla Liang

Update on predator contact points (Cyril, Allison, and Corey) Slides

  • Artificial lighting known to increase predator/prey interaction is not new
  • The way we implement contact point study in first year was to do literature review, supposed to be published now (come up with likely culprits of Central Valley, paired with spatial analysis with how frequently contact points occurred. Highest points to investigate further was submerged aquatic vegetation and artificial lighting)
  • 5 sites, interested in light type (spectrum of light), wanted to pick a warm/cold light that were far apart to see if there was a difference in predation
  • Dotted lines - guidelines, 200 meters long along shore, and approx 20-30 meters wide
  • Two high powered floodlights, beaming on cross section of river
  • Lit area and controlled area have a sonar camera to count predators in different areas to see if light increases aggregation of predators
  • Cold light upstream downstream, warm light repeat, at five sites
  • Results: see slides
  • Unfortunately when there’s no predation in field site, not generating relationship (L6, L7, L8 had low predation for few weeks. Revisited L4 with moderately high predation to see relationship between predation and light).
  • Didn’t collect information generalizable to whole delta, but likely same in many places in delta (relationship between light and predation)
  • Working on incorporating lunar cycle into model, not currently in there because we found lunar cycle would kind of change lux by almost a couple of orders of magnitudes smaller scale
  • relationships between lux and predation based on light hitting water that day (including other things going on in the sky that could affect illumination)
  • PERs tell us if predator rates increased locally
  • If predation increased, is it because more predators, or is it because predators are more effective with illumination around? Don’t have predator density yet
  • Yellow dots in slides = where predation occurred
  • Results of analysis were used in model selection
  • Relationship between lux and relative predation hazard ratio–relative predation hazard ratio 1 means predation risk has not changed. If it’s higher than 1, higher than factor, if lower than 1, decreased than factor
  • Some mortality that occurs at 0 lux
  • Lux, temperature, and time past sunset influence relative predation risk. Would like to know how predator density influences relative predation risk as well.
  • Investigate effects of illumination from bridge/structures in area on survival of fry-sized fish in late/summer fall so that we’re there when winter-run are in their fry life stage.
  • Staff part of project were hoping to investigate submerged vegetation risk on delta
  • LED lights attached to diversion pipes increased the amount of smolt attracted to diversion pipes than when there weren’t lights attached. Evidence there could be possibility both prey and predators are both attracted to the artificial lighting

Update on watershed expert meetings (Mike Urkov)

  • Set to go to Santa Cruz tomorrow, pretty good response, hoping to talk to possibly a couple dozen people, report when that’s done
  • Next phase doing outreach to power and water customers, working on policy questions on that

Discuss Battle Creek winter run proposal (Matt)

  • Fish were collected during drought, genetic material may be rare at this point
  • First year after restock, pretty good return of jacks (95 total, need to be updated in proposal)
  • Based on survival estimates, expecting 500-600 jacks and 3-year olds this year. Idea is that fish returned to 3 locations, 25% going back to hatchery operation
  • Using rotary screw traps to look at juvenile production
  • Expecting production out of creek (hatchery fish) with be more dominated by fish returning to spawn again and again
  • Idea at this point is 3 release locations (one upstream of river, one downstream of Eagle Canyon dam, one upstream of Eagle Canyon dam)
  • Prepared to be flexible on release locations, may have to truck them up there because of barriers
  • Where fish can go based on outreach
  • Rod likes proposal, concerned about the timing of it. Mindful of our overall schedule of producing NTRS, there’s a lot of new incoming information, anticipate that we will have an addendum to NTRS a year from now, start thinking about that if this doesn’t upset the schedule, all for it, but if it’s going to slow us down and delay, Rod has big caution about that
  • Potential downside of not being able to do this for NTRS, battle creek would not be included
  • Could be pulled in things when we update if this is promising in respect to winter-run
  • Battle Creek up in the air with PGE situation, lots of questions around that
  • Mike U: Do we want to put more work on numerical model to incorporate this now, or should this be a priority item in addendum?
  • Not in model at this point, come up to considerations in actions for Battle Creek in NTRS (not priority until other modeling results are done)

Discuss proposed rulesets for restoration strategy development (All)

  • Scenario evaluation like what was done in 2017 prioritizations—4 actions per tributary
  • Mike U: There’s large agreement and then separation in fish returns. We have a case where we have the same result for years 1-7, notable but sp=mall diff 8-14, drought/other 15-17, acceleration at end. For NTRS, we’re talking about concentrations on years 1-7, changes and iterations in model happen in subsequent iterations of NTRS.
  • Mike U: Main idea is to develop paired rulesets (potential rule, and opposite). Example of management restraint: maximize fish returns, minimize fish returns. From group of runs Adam did, take one that does the worst, see what’s causing it to do the worst. Geographical constraint (investment to northern watersheds, and to constrain investment to southern watersheds)
  • Mike U: Also talked about genetic constraints

Review example output that the SIT will be provided with to develop strategies (All)

  • Looking at tributary level, relative to itself
  • Rulesets adopted should be finite
  • Have so much output to look at, hard to process in head
  • Mike U suggests maximum and minimum, only American River and north or South of American, hatchery-dominated vs non-hatchery dominated · East side of the delta tribs should be included in the northern tribs (this is a Matt edit) · Consumnes and Moke are both considered northern group but Calaveras is in the southern

  • How hatcheries vs river defined? Unsure. Streams with hatchery vs streams without hatcheries (Feather, American, Mokelumne, Merced, and Battle are hatchery streams) with inclusion of mainstems

New Business

  • Science Coordinator position: final announcement in the next couple of weeks
  • Rod: monitoring, several 2020 charters incomplete with meeting SIT priorities (ones that required adaptive management plan). Rod would like the SIT to review their design to ask the SIT if they meet the monitoring design that the SIT needs to evaluate and learn from it. They will get request out this week,ask for quick turnaround. He does not have a firm date at this time. He would like to present this to the SIT at the in person meeting and let the SIT have a couple weeks to comment by the 25th of November.
  • Winter-run salmon model workshop concurrent with this SIT meeting, will call in to see data needs discussion