Today I sampled oyster larvae at 14 days post fertilization out at Point Whitney following broodstock PolyIC spawning.

Overview

We followed the same procedure generally as I detailed on 15 October.

Larval sampling and rearing

Today I sampled larvae when Carrie dropped all of the 1K L tanks. We followed similar protocols to the link above for 15 October sampling.

We dropped all of the tanks onto 265 and 240 um screens. The larvae were very pigmented and concentrated! All tanks returned high yield on 240 um screens. Larvae above 240 um were sampled and prepared for shipping.

Larval rearing conditions in these tanks have been consistent (see notebook images below).

We looked at the larvae under the scope - they looked great! Larvae were large and the guts were full in both treatments.

The larvae have feet and eye spots and were very active.

Once the larvae were isolated on the 240 um screen, I took samples by scooping concentrated larvae into tubes with 500 uL RNA/DNA shield.

• Tubes 61-75 = Treated
• Tubes 76-90 = Control
• n=15 per treatment

Samples were taken home and put in the freezer.

Sampled from 08:30-09:00.

After sampling, we weighed the larvae by pouring the larvae into a coffee filter and weighing. Point Whitney has established that 4 g of concentrated larvae equal 1 million larvae.

• Treated = ~25.8 million larvae (>95% survival)

• Control = ~51 million larvae (almost 100% survival)

We have great survival and growth in both treatments.

Larvae from 240 um were prepared for shipping. Carrie packed them in the coffee filter and will ship to Kona today for setting.

Larvae <240 um (extras) were returned to the 1K tanks. Carrie will use these as extras and will ship them in a few days if they are a bit bigger.

13 million treated larvae were shipped and 21.2 million control larvae were shipped.

Probe measurements

tank	date	time	temp.C	pH.nbs	sal.psu	initials	notes
1K_5	10/15/24	09:00	30.6	8.1	NA	carrie	PolyIC-larvae-treated
1K_6	10/15/24	09:00	30.8	8.1	NA	carrie	PolyIC-larvae-treated
1K_7	10/15/24	09:00	30.8	8.09	NA	carrie	PolyIC-larvae-control
1K_9	10/15/24	09:00	30.8	8.11	NA	carrie	PolyIC-larvae-control
1K_10	10/15/24	09:00	30.6	8.12	NA	carrie	PolyIC-larvae-control
1K_5	10/16/24	09:00	28.8	8.21	NA	carrie	PolyIC-larvae-treated
1K_6	10/16/24	09:00	29	8.19	NA	carrie	PolyIC-larvae-treated
1K_7	10/16/24	09:00	28.5	8.19	NA	carrie	PolyIC-larvae-control
1K_9	10/16/24	09:00	28.7	8.21	NA	carrie	PolyIC-larvae-control
1K_10	10/16/24	09:00	28.4	8.21	NA	carrie	PolyIC-larvae-control
1K_5	10/17/24	09:00	28.7	8.22	NA	carrie	PolyIC-larvae-treated
1K_6	10/17/24	09:00	29	8.2	NA	carrie	PolyIC-larvae-treated
1K_7	10/17/24	09:00	28.4	8.18	NA	carrie	PolyIC-larvae-control
1K_9	10/17/24	09:00	28.6	8.2	NA	carrie	PolyIC-larvae-control
1K_10	10/17/24	09:00	28.1	8.19	NA	carrie	PolyIC-larvae-control
1K_5	10/18/24	09:00	28.7	8.1	NA	carrie	PolyIC-larvae-treated
1K_6	10/18/24	09:00	29	8.11	NA	carrie	PolyIC-larvae-treated
1K_7	10/18/24	09:00	28.3	8.11	NA	carrie	PolyIC-larvae-control
1K_9	10/18/24	09:00	28.4	8.14	NA	carrie	PolyIC-larvae-control
1K_10	10/18/24	09:00	28	8.14	NA	carrie	PolyIC-larvae-control
1K_5	10/19/24	09:00	28.6	8.13	NA	carrie	PolyIC-larvae-treated
1K_6	10/19/24	09:00	28.8	8.1	NA	carrie	PolyIC-larvae-treated
1K_7	10/19/24	09:00	28.2	8.09	NA	carrie	PolyIC-larvae-control
1K_9	10/19/24	09:00	28.6	8.09	NA	carrie	PolyIC-larvae-control
1K_10	10/19/24	09:00	28.2	8.06	NA	carrie	PolyIC-larvae-control
1K_5	10/20/24	09:00	28	8.1	NA	carrie	PolyIC-larvae-treated
1K_6	10/20/24	09:00	28	8.15	NA	carrie	PolyIC-larvae-treated
1K_7	10/20/24	09:00	28	8.12	NA	carrie	PolyIC-larvae-control
1K_9	10/20/24	09:00	28	8.15	NA	carrie	PolyIC-larvae-control
1K_10	10/20/24	09:00	28	8.15	NA	carrie	PolyIC-larvae-control

Fluorometry measurements ranged from 20-40. They are eating lots and had high quality food!

Flow was 2-2.4 in all tanks.

Temperatures were consistent.

Notebook images