Baywater Outplant Assessments and Deployments 20 August 2025

Today we assessed 10K seed outplants at Baywater Shellfish in the Hood Canal, WA and outplanted the remaining PolyIC seed for future assessments.

Overview

In October 2024, we outplanted 10K seed at Baywater Shellfish in Thorndyke Bay, WA. Today, we are assessing oysters for growth and survival and then redeploying them for the rest of the summer.

We also outplanted the remaining PolyIC seed, which were also deployed this summer at Sequim Bay.

10K seed assessment

We pulled in all of the cages that we located last week. All 30 bags were still in place on the lines.

We then did the following things for each bag:

  • Empty the bag onto a table
  • Count the number of dead oysters and remove any mussels, crabs, empty shells, and other debris
  • Imaged all oysters with a scale bar for growth analysis using ImageJ
  • Added a new yellow ID tag
  • Moved oysters into a new clean bag with the new tag
  • Moved loggers into the new bags

The bags were processed and will be redeployed tomorrow onto lines. Here are some notes from today:

  • Two bags were completely empty. One was open and oysters likely fell out. One was closed but contained no oysters.
  • Some bags had <10 oysters. These oysters were imaged but were not redeployed in new bags. We therefore had 6 bags that were not redeployed (24 bags for the 10K project were redeployed)
  • Some bags had a mixture of large and small oysters. In some cases, we found dead/empty shells either of small or large oysters and we recorded the number of alive/dead for each size. It is likely that the small shells were winter mortality and the large shells are summer mortality.
  • Bags were left at the processing center and will be added back onto the lines tomorrow. Processing occured from ~09:00-12:30 today.
  • Logger batteries were full and memory was only at 30%.
  • Yellow tags were added onto exterior of bags.

Here is an example of the size images:

Here is the outplant data.

purple.tag source.bag treatment number.oysters 20250820.tag 20250820.notes 20250820.loggers 20250820.mortality
1 75 FW 35C 150 400     1 large
2 75 FW 35C 150 328     6 small
3 75 FW 35C 150 304      
4 76 FW 35C 150 301     7 big, 8 small
5 76 FW 35C 150 306      
6 76 FW 35C 150 318   22023410 4 big, 12 small
7 47 35C 150 311     5 small
8 47 35C 150 309      
9 47 35C 150 316     4 big
10 30 35C 150 315     2 big
11 30 35C 150 319     1 small, 1 big
12 30 35C 150 317      
13 49 Immune 150 NA not rebagged, <10 oysters   1 big
14 49 Immune 150 305      
15 49 Immune 150 302      
16 50 Immune 150 NA not rebagged, <10 oysters    
17 50 Immune 150 NA empty, no oysters    
18 50 Immune 150 303      
19 66 FW 150 NA not rebagged, <10 oysters    
20 66 FW 150 312      
21 66 FW 150 NA not rebagged, <10 oysters    
22 56 FW 150 307      
23 56 FW 150 308      
24 56 FW 150 314     1 big, 23 small
25 37 Control 150 NA bag open, no oysters remaining    
26 37 Control 150 329      
27 37 Control 150 310   22023411  
28 36 Control 150 313     6 small
29 36 Control 150 320     3 small
30 36 Control 150 330   22023406  

Data are on GitHub here.

PolyIC Seed Deployment

Today Steven picked up the PolyIC oysters from Point Whitney and we outplanted at Baywater. The seed were still too small for the bags, so we used the following steps to deploy:

  • Combine the duplicate Control (green tags 49 and 47) and, separately, combien Treated (green tags 45 and 48) mesh bags from Point Whitney dock lines
  • Screened oysters from each treatment though the bag to have one bag of “large” seed
  • Split the remaining seed (“small” seed) between 1-2 mesh seed bags. These seed bags were then placed inside of outplant tumble bags. We will need to return in 1 month or so to remove the mesh bags.
  • We will use images to estimate numbers and size of oysters in each bag.
  • Yellow tags were added to the exterior of bags.

We have a total of 5 PolyIC bags and therefore a total of 29 bags at Baywater.

Here is the outplant data:

source_tag outplant_tag treatment rearing_tank number logger deploy.date notes
49/47 326 Control NA NA   20250820 larger oysters, not in mesh bag; refer to image for number and size estimates
49/47 325 Control NA NA   20250820 small oysters, in mesh bag; refer to image for number and size; accidentally labeled as 326 in photo for measurements
49/47 327 Control NA NA   20250820 small oysters, in mesh bag; refer to image for number and size measurements; refer to image for number and size estimates
45/48 323 Treated NA NA   20250820 larger oysters, not in mesh bag; refer to image for number and size estimates
45/48 324 Treated NA NA   20250820 small oysters, in mesh bag; refer to image for number and size measurements

Data are on GitHub here.

Next steps

Written on August 20, 2025