EURO-BASIN Mesocosm 2012: Day 27 (Aug 25 2012)

Hurrah! We killed the Agg Bags today. That was kind of fun. That half of the experiment is now OVER (or at least it will be in another three hours, after we have finished processing the samples of the biofilm that grew on the insides of the bags, something we did not have the energy to face last night, so we just stuffed square pieces of the bag in the fridge to wait for today).

What you had to do was first pull up the bag until you could not lift it any more, because the bag was completely filled with water (to the bursting at the seams point, nevermind that it doesn't have any seams except at the bottom). As soon as you could lift the water in the bags a centimeter or two above the level of the ocean water, you were certain that the bags were perfectly plumped out. Then you measured the distance between the height of the water in the bag and the 0 meter mark on the plastic. This told you the exact length of the bag (since we measured them out to be a perfect 10 meters plus the cone bottom which was traced out from a pattern). Thus, knowing the diameter of the plastic bags, we can now calculate the volume of water in the bags at the end of the experiment (which should be somewhere between 6000 and 7000 liters). And since we have only taken out perhaps 100 liters (maybe double this in some bags), we actually know the volume at the beginning of the experiment to at least within 5 or 10 %.

Tomorrow, after Richard has made a solo attempt to count the Bolinopsis remaining in his bags at the end of the experiment (which could be an interesting thing to do, but which everyone else thinks is a waste of time, seeing as how it has not been done at any point before the end of the nearly 3-week experiment and we certainly have seen the populations rise and fall and rise again, in some cases), we will kill the calcite bags. Then all there is left to do is tow in and dismantle the mesocosm raft structure, pack up, get our boxes and our precious frozen samples shipped of hither and yon, and then clean up and go home. It is certainly more than time.

Julia left us this morning. At mealtimes, the table is beginning to look desperately thin. It's got this definite And Then There Were None feel to it.

Aug 25 2012a- The crack mesocosm destruction team.

Aug 25 2012b- Pulling in the boat.

Aug 25 2012c- Piling into the boat.

Aug 25 2012d- Riding out to the mesocosms.

Aug 25 2012e- Juli giving me another of her shame on you, you're taking a picture of me looks.

Aug 25 2012f- Morgane is very happy to be going out to kill the agg bags.

Aug 25 2012g- Beginning to dismantle the first one.

Aug 25 2012h- Morgane playing the puppeteer.

Aug 25 2012i- Handing me the implement of incision.

Aug 25 2012j- Slicing it open and hauling the plastic into the boat.

Aug 25 2012k- It's kind of fun, actually.

Aug 25 2012l- Moving on through the set of agg bags.

Aug 25 2012m- The anoxic goo at the bottom was quite whiffy.

Aug 25 2012n- Grabbing the weight at the bottom of the bag.

Aug 25 2012o- The first empty ring. *sniff*

Aug 25 2012p- While waiting for half the crew to deposit the first half of the bags onshore, Nathalie makes friends with a baby lumpsucker fish that had taken a shine to the bottom of one of the big black mesocosm framework rings.

Aug 25 2012q- Attack!

Aug 25 2012r- One of the baby lumpsucker fish.

Aug 25 2012s- The lumpsucker fish swimming off into the great blue.

Aug 25 2012t- Time to kill the last agg bag.

Aug 25 2012u- The fatal tear.

Aug 25 2012v- Morgane got very good at this.

Aug 25 2012w- DONE! YAY!

Aug 25 2012x- Juli turning away from the camera as I take a picture of the plastic bag mound in the boat.

Aug 25 2012y- Mission accomplished.

Aug 25 2012z- That deserves a second shot.

Aug 25 2012za- Leaving the now half empty mesocosm raft.

Aug 25 2012zb- Our triumphant return, spear aloft.

Aug 25 2012zc- Nathalie demonstrating proper bow riding technique.

Aug 25 2012zd- Jussi steering while staring into a solid wall of plastic.

Aug 25 2012ze- It is the right hand you salute with, right?

Aug 25 2012zf- Juli is very proud of our haul of plastic.

Aug 25 2012zg- Hauling them out of the boat, bucket brigade style.

Aug 25 2012zh- The sliced open bags being passed along up the dock.

Aug 25 2012zi- Briva is looking happy for someone who has been mouth pipetting fecal pellets all afternoon.

Aug 25 2012zj- She must have taken Morten up on his offer. He is quite the entrepreneur.

Aug 25 2012zk- The zooplankton team donated their home made plankton net as the memorial creation to mark our stay here. Juli made sure that everyone signed a tag.