Laura’s Notebook: Manchester, 6/15

Screening day. Some hiccups, but nothing devastating. Grace screening, Olivia working buckets/setup, me sampling/counting. Initial visual inspection of larval buckets look like larvae aren’t doing as well as they were last week. But, we’ll see!

Data: imageimage

Snafoo: the SN-10 Ambient group was mislabeled as SN-10 Low, and before realizing I stocked the 224um larvae (of which there were ~30k!) in the SN-10 Low setting tank. This error was caught moments later, and labeling/data entries were corrected. Unfortunately, the SN-10 Low setting tank, which had been stocked with ~4,300 larvae since 6/5 and which I know there were still swimmers, is now mixed with ~30k SN-10 Ambient larvae. I started a new SN-10 Low setting silo. I kept the mixed up batch, labeled as such. Most of the animals in this group are from SN-10 Ambient.

TBD ….. more info…

from The Shell Game

Laura’s Notebook: Manchester, 6/13 & 6/14


  • Temperature in system has fallen consistently over the past couple days- it was ~16degC. Noticed that the immersion heater I borrowed from Jon was reading 17degC, but was not heating. I swapped in the spare heater that we had purchased, and set it to 19degC. Will observe over the next couple days.
  • Checked on temp of upwelling tank outside: 17degC. This is sufficient- I will not install a 2nd heater.
  • Purchased pvc part and installed in a Calwell tank, which I will use tomorrow to feed the upwelling tank- hopefully I have some setters!
  • New larvae present in: SN-6 low B (some), HL-6 low (a tiny bit). Did not collect today, will do so tomorrow.
  • Connected the 100um and 180um buckets and adjusted flow/banjos for the 2-Bucket Challenge. Built new double-buckets for new larval groups.
    • Notes on bucket configuration:
    • I separate SN & NF groups into 2 buckets, 100um and 180um, after screening, but do not separate the K & HL groups (limited number of banjos). Mortality rate in the >180um group is considerably lower than in 100um; by separating the groups I minimize risk to the 180um, AND I maintain capacity in the 100um buckets to stock new larvae.
    • 2 days prior to screening I connect the 2 buckets in SN & NF groups, setting flow in the 1st (100um) bucket, where live 100um larvae will flow into the 180um bucket. For K & HL groups, I install a 2nd, bucket, pushing live larvae from old bucket to new bucket.
    • I screen on Mondays & Thursdays (usually); buckets are therefore connected in their 2-Bucket Challenge configuration on Tuesdays & Saturdays. The size groups are thus separated for 1 or 2 days.
  • Gigas:
    • Increased temp by 1degC – 17degC
    • Removed bags, sprayed with fresh water, inspected for morts – no morts observed
    • Tried vacuuming tanks, but instead drained completely with siphon, as water had become very dirty when removing bags.


  • Arrival inspection:
    • All larval banjos very dirty. A couple buckets nearly overflowing. Changed banjos immediately.
  • Screened and cleaned setting tanks and checked for set larvae:
    • Setters visibly inspected by first screening on to 450um, and viewing under microscope. Not very many, so I also sampled from the rest of the contents that did not hold on the 450um. Saw some newly set oysters, as well as lots of larvae that had yet to go through metamorphosis.
    • Cleaned setters/culch/larvae in freshwater bath
    • Oyster set observed in:
      • NF-6 Ambient – lots of swimmers too
      • SN-10 Low – lots of swimmers
      • NF-10 Low – very few swimmers file_000
      • NF-10 Ambient – very few swimmers, here’s a photo of an oyster set: file_000 1
      • HL-10 Ambient – a couple set
      • K-6 Low – no larvae visible in the sampled contents
      • K6 Ambient – just 1 setter, lots eyed larvae
      • K-10 Low – lots of morts, 1 larvae set visible
      • Here’s a video of the SN-10 Ambient group, in which I didn’t see any set oysters, but there were lots of swimmers:
    • Not enough setters to warrant using the outside upwelling tank. Returned all larvae/set to the 180um silos in the downweling tanks.
  • Collected new larvae: image
  • Changed filters
  • Rinsed larval catchment buckets
  • Increased Gigas temp to 18degC. Heater does not appear to be keeping up with the flow rate. Will continue to increase temp by 1 degC/day, as to not shock them.

from The Shell Game

Laura’s Notebook: Manchester, 6/12

Screening day- Arrived at 8:30am, geared up to screen through the larvae. Grace worked the screening table, Olivia managed the buckets and whatnot, I counted and re-stocked larvae, and Katie took video and images. Finished at ~2:00pm. Things went very smoothly and we got a good routine down. Here are snap-shots of the data:


After restocking, all buckets were fed 700mL algae cocktail of: 1/4 Tet, 1/4 609, 1/2 Chagra.

Images: using my phone & the new cell phone adapter, Katie imaged and observed activity. Images were taken using my phone. Here are her notes:


I fixed all screened larvae with Lugols and stored in fridge for size imaging (under the scope with the scale) at a later date.

Collected new larvae, counted, sampled, and stocked:

  • HL-6 Ambient
  • HL-10 Low
  • K-6 Ambient
  • SN-6 Low B
  • NF-6 Low A

Other activities:

  • Arrival inspection:
    • All buckets very clear, likely have been without food for several hours.
    • It appears the dripper was left out of NF-10 Ambient B since Saturday. Air stone was still in there; no apparent mortalities.
    • Aeration was not sufficiently high on the west side of the larval table (mostly on K & HL groups).
    • Temperature in the whole system has dropped to ~16degC, possibly due to it being pretty cold outside…?
  • Rinsed all larval catchment buckets
  • Checked on the upwelling tank outside; it is holding at 17degC
  • Gigas:
    • Grace & Olivia cleaned, inspected for morts (none)
    • Grace measured and adjusted flow rate to set a 1.2L/min per side
    • I increased temp 1degC; temp was reading 15degC, so I set heater to 16degC
    • Installed aquarium pump in header tank, fed with 490mL Reeds Shellfish Diet, and set dosing pump to 57

from The Shell Game