Sea stars, also known as starfish (this latter term is a bit of misnomer considering they are certainly not "fish"), are common sea floor animals that are found in all the world's oceans. Most have five rays or arms, but others can muster as many as twenty-five to thirty as saw my previous "Unexpected Surprises" post. Their arms are lined with legions of tiny tube-feet that operate using a unique hydraulic plumbing system that squeezes water through tubes with tiny valves that open and shut. The tube-feet serve primarily for locomotion, but also play a role in food capture and sensing prey.

On Monday this week we built 18 mesocosm "universes" in the Palmer Station aquarium. That may sound a little out of this world, but let me explain. This week we started our mesocosm experiment, utilizing the relationship a large species of brown algae (the same big branched brown Desmarestia menziesii I mentioned in a previous post) and all of the amphipods on it. We created smaller simulated natural "community" assemblages from carefully collected Desmarestia. See the image right for my multple universes, complete with air lines and pH probes.

As Chuck hinted in Dive Ops, part 1 this entry will focus on the tender side of our diving operation. Tender, in our vernacular, is used as a noun and refers to the act of tending to one's needs – in this case – a diver's needs. All of our dive operations have two divers and two tenders. Every project member routinely serves as a tender and often a volunteer or 'town tender' substitutes for one of us so that member can remain on station to instead tend to lab work. The other day I served as project tender and had the delightful assistance from town tender Harry Snyder, the winter-over carpenter. In addition to extraordinary wood working skills, Harry jams smiling at ease on the guitar and at the throttle of a zodiac as pictured.

The day I prepared to leave Palmer Station, I took a final glimpse from my dorm window at the splendid architecture of the glacier. I finally had an opportunity to climb the glacier and walk to its far side, days before I left. Crossing the field of boulders in the back yard, separating Palmer Station from the glacier, was a long walk. I eventually reached the glacier and began my ascent, aided by the spikes I affixed to my boots for stability on the ice. I climbed higher and higher; soon, Palmer Station was barely visible.

Scuba diving is a central part of our research here. We call it "Dive Ops" which is short for Diving Operations. All our experimental manipulations on this project are done in the lab but since the organisms we are studying live along the bottom of the ocean (described then as benthic organisms), Dive Ops are critical in order to collect them and their food. Today Julie and I needed to dive to collect food for the amphipods (shrimp-like animals) that she is working with in the lab and also some more amphipods for upcoming experiments.


Palmer Station Webcam