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The following is a summary of a trip to Jamestown Point Whitney Shellfish Hatchery in Brinnon, Washingston frmo 3/6/20 - 3/13/20.

About the trip..

Prepare heathstack for 8-month rearing trial starting from 30-day-old pediveliger (setter) stage well in to juvenile development.

• Experiment will contain three main Ω_{aragonite.sat} treatments controled in triplicate

  (1) ambient p_CO₂ = _Ω_{aragonite.sat} > 1; pH_t.s. 7.8-7.9;

  (2) moderate elevated p_CO₂ = _Ω_{aragonite.sat} 0.4; pH_t.s. 7.4;

  (3) severe elevated p_CO₂ = _Ω_{aragonite.sat} 0.1-0.2; pH_t.s. 7.1;

• Continuous live algae feed and isolated seawater flow per replicate tank/tray

Heathstack up and running

• nine trays total each fed by a conical sump for three total _p_CO₂ treatments

  

Algae plan

• the broodstock are fed from a continuous flow of live low density culture from the greenhouse
• a flow switch in the feed conical prevents pumps from burning
• our plan discussed with Mat that 400 - 600 L will be possible per day to add to this conical. This equates a rate of 1/2 GPH for each heathtray

Reciprocal treatment transition

• Experiment will contain two periods (months 2 and 4) when animals will be divided and allocated to different treatments to address the effects of stress priming on subsequent encounters
• review “2020-03-12_8_month_OA_Experiment_Plan” for further details
• replication will require custom tanks with trays acting as a water. It is critical that seawater is not exchanged between tanks

Scope for Growth build

• P = [C - (R + U)]
  • R respiration rate: measured with SDR dish at the hatchery; freeze all animals in -20C for AFDW as loss of ignition in Putnam Lab
  • U ammonia excretion: freeze water samples from respiration rate measurements (~3-4 ml individual^-1) for later analysis
  • C ingestion rate and absportion efficiency:
• For ingestion rate & absortion efficency, it is critical that sw+seston is homogenous for Nexcelom Cellometer readings pre and post incubation. The animal(s) will also need to be suspended on a platform to avoid disturbance from the magnetic stir bar below.