Thur. Sept. 19, 2019 Pt. Whitney Juvenile Var.low pH experiment
Posted on September 19, 2019
Water chemistry
Took discrete measurements and TA around 2:30pm
for TA, I took directly from the discrete measurment water after filtering it through 20uM. The discrete measurement water samples were directly from the headers and inside the silos (using clean TA cups)
everything looked as it should
@5:40pm calibrated B5 which was off by 0.08. All other probes were within 0.01.
Animal check
Tote B5 had a pretty low water level and Matt and I weren’t really sure why. He said the header upstairs was overflowing so he turned that down and it should give more water to the totes. He also turned the pump up a little bit. The animals in B3 were still receiving water although the flow felt a little weaker by the touch. I doubt it has been like this for a whole week, it seems anomlymous.
Algae line looked a little clogged, like it wasn’t really flowing. However disconnecting from the tote inflow pipe looked like it was dispensing the same volume as the lines going into the conical headers. Also algae came out from the tap near the pump head itself when turned on. So all good here.
Respirometry and sampling
filled 5L beakers with 1-2L 1uM FSW.
Submerged vials in well plate holders
turned off flow in silos and removed manifolds
took 1 animal/silo with transfer pipette spoon and then used 2 transfer pipettes like chopsticks to transfer the animal into the corresponding submerged vial
Did this for all silos, took about 20 minutes
Turned flow back on immediately after transferring animals and adjusted to 7mL/sec.
Noticed animals in low pH treatment had very fragile shells and are a little white like Sam has previously seen
it seemed like animals from ambient parents were more fragile (many broken shells on the sand surface.
Ran 1 respirometry trial around 5pm for about 30 minutes.
SDR plate positions here (A1 = bottom right corner):
on SDR plate:
After trial, emptied vials and animals onto a well plate lid (to track their positions; A1 = upper right corner and order listed on size measurement data table linked below) for shell length measurements
Got wet weight for each animal by transfering animals onto paper towel (using the transfer pipette chopstick method) to gently blot off excess water. Then transferred animal into tared snap cap tube, recorded weight, and immediately froze in liquid N2.