Laura’s Notebook: Manchester 7/3

Screening day, preserved growth exp. larvae, changed growth exp water, collected new, cleaned downwellers.

Just me and Grace today, but all was very manageable.

Cleaned outside downwellers

Again, green film is clogging the silos; rinsed with fresh. Lesson learned: do NOT use tetraselmis algae (the green one). It’s large, and clogges everything. I spoke with Stuart, and he has agreed to not feed any of my system Tet moving forward.

Screened larvae

Larvae numbers are dwindling. High mortality last week, as well as minimal newly spawned larvae, equals extremely low counts. [screening data here as soon as I digitize]

New Larvae

image I had previously planned to cease stocking new larvae on 6/30, BUT this group, NF10 Low, had an enormously high mortality event so I opted to keep these ~40k larvae and move them through to (hopefully) set.

Water change on SN growth exp


Transferred all SN growth exp larvae into tubes for safe keeping

As advised by Katherine, I had Grace transfer all the SN growth experiment sampled larvae from 6/22 & 6/29 into labeled tubes. Grace labeled them with date and well #; well #’s corresponding treatment and rep are located on my master larval data spreadsheet. NOTE: I do not have saved larvae from time 0 (6/15), as I did not have the forethought to do so.

Running list of lessons learned:

  • trust but verify
  • be explicit
  • avoid Tetraselmis
  • cull all groups

Consideration: was it necessary to have 2 spawning groups per treatment, given the long time-frame? AKA is it realistic that one male would fertilize all females over 2 months?

from The Shell Game