This post details activities at Point Whitney from 22 May 2024 trip.

Overview

Today we went to Point Whitney to prepare for the next round of field outplanting and experiments. We also conducted weekly stressors.

Weekly probe measurements

We took weekly measurements and did fluorescence measurements before and after feeding. I added about 1/3 of a 5 gal bucket to each tank of food. Also filled the header feed tank.

Feeding measurements

tank	pre feeding	post feeding
left tank	3	36
left tank (silo)	2	13
left tank (silo)	2	15
middle tank	4	11
middle tank (silo)	1	14
middle tank (silo)	1	24
left tank	3	47
left tank (silo)	1	11
left tank (silo)	1	17

Environmental measurements

tank	date	time	temp.C	pH.nbs	sal.psu	initials	notes
right	5/22/24	11:30	14.9	8.17	29.85	ash	tank
right	5/22/24	11:30	15	8.17	29.87	ash	silo
right	5/22/24	11:30	15	8.18	29.88	ash	silo
middle	5/22/24	11:30	14.5	8.16	29.86	ash	tank
middle	5/22/24	11:30	14.5	8.16	29.86	ash	silo
middle	5/22/24	11:30	14.5	8.16	29.89	ash	silo
left	5/22/24	11:30	14.5	8.16	29.92	ash	tank
left	5/22/24	11:30	14.5	8.16	29.9	ash	silo
left	5/22/24	11:30	14.5	8.16	29.9	ash	silo
outdoor_tray	5/22/24	11:30	14.5	7.72	28.69	ash	large POGS
outdoor_tray	5/22/24	11:30	14.5	7.73	28.64	ash	small POGS

Weekly stressors

We conducted weekly fresh water and thermal hardening as usual from 11:41-12:11. This included large and small 2023 POG cohorts.

Stress conditions were 23.5°C in the temperature stress (7.78 pH and 30.31 salinity). Conditions were 14.5°C in the fresh water stress (pH 8.31 and salinity 0.181).

Cleaning and resetting tank system

We moved all animals from middle and right tanks to one upweller outside. They will have natural food concentrations and ambient conditions until outplanting. We put animals from all silos into one orange bag (one bag for ambient animals, one bag for hardened animals from daily exposure).

3 adult families were moved outside, 2 were kept inside. We left the LCO project tank (left tank) running as normal.

We then drained and rinsed the middle and right tank and took down temperature equipment. Tanks are now ready to add HUDL’s or conduct new hardening trials.

This is the system now:

We will work on finding the equipment and set up that we want for HUDLs over the next couple of weeks. We want to streamline water delivery and air line delivery to make the system cleaner and easier to use.

Point Whitney will also likely have some extra larvae in the next few weeks that we can use to optimize and test our rearing system.

Field outplant planning

Here is an outline of the number of animals we have available for outplanting:

• Outdoor trays
  • “small” 2023 POGS: 2 stress trays with about 700 animals per tray and 2 control trays with about 700 animals per tray. This will allow for ~1400 control and ~1400 hardened seed. From this, we can do 100-150 seed per bag/basket for a total of 10-14 units per treatment. We will try to do 5-7 baskets or bags of each condition at Westcott and another 5-7 of each condition at Goose Point.
  • “large” 2023 POGS: We have about 300 control and 300 stress animals from the temperature weekly treatment. We have about 650 animals in the control and 400 in the stressed from the weekly fresh water treatment. From this, we will pick one site and send all individuals to one site (about 3 bags of each condition in temperature stress and about 4-5 bags of each condition in fresh stress).
• Indoor POGS daily hardening
  • All seed from silos will go to one site. We have n=16 groups of 50 seed with n=8 from hardened and n=8 from control. We also have some seed from bulk exposure bags that can go into these.

Total outplants to Westcott:

• n=14 total bags of “small” 2023 POGS thermal hardening (weekly)
• n=6 total bags of “large” 2023 POGS thermal hardening (weekly)
• n=8-10 total bags of “large” 2023 POGS fresh water hardening (weekly)
• n=16 total bags of indoor 2023 POGS thermal hardening (daily). We can reduce this if we increase number of animals per bag.

Total outplants to Goose Point:

• n=14 total baskets of “small” 2023 POGS (100-150 animals per basket) to Goose Point. They have 15 baskets for us, so we can go up to 15. Thermal hardening (weekly).
• Seapa baskets at 12mm mesh. Must select animals >12mm.
• Outplant these either next week (Thurs/Fri) or in mid/late June. Kathleen will confirm date with AH early next week and AH will drive animals out to the coast on the outplant day.

Broodstock planning

Next week, we will use half of the animals of 2 families to trial broodstock hardening. We are going to try fresh water and mechanical exposure on n=10 of each family with n=10 of each family left at ambient as a control. We want to find hardening treatments that stress the animals without inducing spawning. We will try this next week. If some animals do spawn, we will still have n=10 from the control condition to work with for spawning.

Notebook images