Field work notebook posts from 17-20 September at Point Whitney.

September 17

Today I went to the Point Whitney hatchery to conduct continued 10K Seed stress hardening and check on broodstock gamete development.

1. 10K stress hardening

I conducted another round of stress hardening as described in Steven’s notebook. The temperature exposure is occuring in the lab on a daily timer of exposure (36°C between 11pm-5am daily). I took bags 75/76 and 56/66 and added each bag to an individual 5 gallon bucket in fresh water for two hours from 10:30-12:30. Bags were then moved back to indoor tank (75/76) or the lagoon (56/66).

2. Photos of 10K seed for growth and numbers

I took images of seed for the 10K project from bags 47, 75, 76, 56, and 66. For each bag, there are two photos (bag “a” and bag “b”). All seeds are contained within the two photos. I added a caliper for size reference and a notepad with the bag and photo letter in each photo.

We will continue to analyze these images for number of oysters in each bag and average size before outplanting as described in this issue.

All images are uplaoded to this directory in GitHub.

I’ll add the remaining bag images (30, 36, 37, 50, and 49) when I go out on Friday of this week.

Here is an example of what these photos look like:

3. Broodstock gamete status

I opened 2 broodstock oysters (each from different bags - bag 34 and 28) to look for gamete development. While doing this, I checked all broodstock bags for total number of alive and dead oysters so we know what we have to work with for potential spawning. I removed 1 from bag 34 and 1 from bag 28, so that is why those bags have 19 total oysters.

Several of the bags had fresh water exposure from earlier in the summer, which is noted below. If a “control” or “exposed” is not present, that means that the family did not get included in the fresh water exposure from earlier in the summer.

• Bag 34 = 19 alive, 0 dead (family 27.014)
• Bag 35 = 8 alive, 1 dead (family 27.009; control)
• Bag 28 = 19 alive, 1 dead (family 27.025)
• Bag 99 = 10 alive, 0 dead (family 27.052; treated)
• Bag 100 = 8 alive, 0 dead (family 27.009; treated)
• Bag 26 = 19 alive, 1 dead (family 27.039)
• Bag 29 = 13 alive, 1 dead (family 27.052; control)

Interestinly, 1 died in each control bag with 0 dead in each treated bag.

Of the oysters I opened, 1 was a male and 1 was a female! I saw sperm and eggs in the microscope. I have included images below. The gamete area was medium in size, so perhaps in a couple weeks each oyster will have more gametes. Carrie looked at the sperm and eggs on the scope and said they looked good and could be ready for spawning in a couple weeks.

Male:

Female:

Eggs:

4. Loggers

I downloaded all temperature loggers today. I also launched a new logger (SSN 22023407) in the indoor temperature exposure tank logging every 10 min. We have 1 new logger left we can deploy during outplanting.

The logger from the 10K seed lagoon is on GitHub here and the loggers from outdoor tanks and trays are on GitHub here.

I need to plot the data from all these loggers ASAP.

To do on Friday

On Friday, I will do another round of stress hardening treatments and finish taking images for bags 30, 36, 37, 50, and 49.

We also need to decide what to do with Effort C project dip/trip families that underwent exposure to daily temperature increases alongside Effort B oysters. We are currently testing survival in the lab for Effort B and I’ll see what those results say. We could either do more survival assays in the lab for Effort C or outplant to the field.

Notebook images

September 20

Today I went to Point Whitney to finish images of 10K seed bags and conduct another round of fresh water stressors.

1. Continuing stress

I conducted another round of stress hardening as described in Steven’s notebook. The temperature exposure is occuring in the lab on a daily timer of exposure (36°C between 11pm-5am daily). I took bags 75/76 and 56/66 and added each bag to an individual 5 gallon bucket in fresh water for two hours from 10:00-12:00.

All bags were taken back to the lagoon after the fresh water stress. We will now let the bags be in the lagoon for a couple weeks before outplanting.

I cleaned all tanks and removed all heaters and pumps.

2. Photos of 10K seed for growth and numbers

I took images of seed for the 10K project from bags 30, 36, 37, 49, and 50. For each bag, there are two photos (bag “a” and bag “b”). All seeds are contained within the two photos. I added a caliper for size reference and a notepad with the bag and photo letter in each photo.

We will continue to analyze these images for number of oysters in each bag and average size before outplanting as described in this issue.

All images are uplaoded to this directory in GitHub.