Life is never dull in Antarctica. Since our return from field camp, we've still been diving and going on SCINI missions on the ice in front of McMurdo. However, we have also had a busy week of day trips to various other spots on the ice. Most of the team spent two day trips recovering Paul's experiments and flying SCINI at a place across McMurdo Sound called Salmon Bay. Here Paul's experiments were actually on top of the ice as the anchor ice had lifted them up. Recovering them was not as exciting though Paul was still able to study the seafloor using SCINI.
Yesterday, DJ, Paul, and Jen were back on the ice in front of McMurdo taking SCINI to a record depth of 320 feet.
While they were based at our home site, Stacy, Kamille, Kevin, Julie and I took a trip across McMurdo Sound to a crack in the ice in front of an island called Bratina Island. This tide crack is estimated to be about 10 miles long. Last year it was open in many places but this year it was mostly closed and covered with snow and ice.
View from the Helicopter - Did you think the ice in Antarctic looks like this?
The helicopter dropped us and our survival bags off. We always have to be prepared for the worst here in Antarctica.
We walked from one end of the crack to the other - about 3 miles of up and down, over slippery ice and through deep snow.
We were on various marine animal survey missions. One mission involved trying to find fish heads left by Weddell seals, the same type of seal that you read about just a few days ago that another research group is counting and weighing. Stacy and her collaborators investigated this area, in 2009 and found 45 fish heads along the crack. They think that Weddell seals eat most of these fish, the Antarctic Toothfish, commonly known as the Antarctic cod, but that they do not eat the heads. They believe that these fish heads then float to the surface and, as the sea ice ablates, are finally brought to the surface of the ice. Finding these heads in this location told Stacy and her collaborators that these large fish might be the main food for seals that are here, far from open water. So what happens if we continue to overfish this fish like we are also doing with its relative, the severely over-fished Chilean Seabass (otherwise known as Patagonian Toothfish)? How will this affect the seals here along the crack?
The WATER DROP from Tina's Cabrillo English 1A class came along to help.
Curiously, this year we only found a few fish heads. We didn't find 45 like they found last year. Was there too much snow hiding them? This year, we also wanted to see how old the fish are. Tiny ear bones in the heads of the fish called otoliths have rings similar to trees which tell the scientists the age of the fish.
Here, Stacy explains what the earbone of the fish, the otolith, looks like.
Kevin is trying to find the otolith. Can the WATER DROP from Tina's Cabrillo English 1A class help?
We think we found one. Can you see how tiny it is compared to the fish head?
Unfortunately, finding the otoliths was also not that easy. Hence, we stuck the fish heads we found in plastic bags and carried them with us on our hike so we could bring them back to study in our lab at McMurdo. What will we find? We'll still have to wait and see.
In addition to our fish head and otolith mission, we also were on a scavenger hunt for invertebrates like sponges and bryozoans for Paul. Again we only found a few, freeze dried on the surface of the ice.
How big is this sponge? Where is it located? We took pictures of each organism we found with a ruler so we could tell how big it is and a GPS that displays the coordinates and records a way point.
Along the way we found a few seals near the crack. They come up through holes in the crack.
Sadly we found many dead seals as well. We think the crack freezes back shut and traps them on the surface - away from their food.
At the end we had spent the whole day hiking. We were pretty tired.
After yesterday's day of hiking, we took our trusted vehicle, the Tucker north today to Stacy's last monitoring site - Turtle Rock. This site is about 6 miles from McMurdo, a good one and a half hour Tucker ride. It's also on a spot in the ice covered in cracks which means we couldn't get LT and his big Reedrill to make holes for us. They'd fall in! Thus, we had to find cracks to use as entry points for our divers.
Stacy and Kevin try to find a hole in the crack so they can SCUBA dive.
Stacy gets ready to jump in. This time there's no hut and we didn't have to drill the hole.
Kamille helps Kevin get ready to jump in.
Kevin is in the hole. Underwater they will have to find the hole to get back out.
This seal jumped in after Stacy and Kevin and they enjoyed watching it underwater.
With that dive, we are now done with Stacy's monitoring! The last of the pictures are being uploaded and backed up as I speak and Kamille has already sieved the samples!