29 Nov 2013 – Hunting for worms (63o 40’S 59o 43’W)
Let’s talk about worms. More specifically, I want to talk about marine segmented worms, also known as polychaete annelids. Our first box core and Blake trawls were full of them. Many were hiding in tubes, others were happily digging their way through the mud. Some were long and skinny, others short and fat. Some were microscopic, some were half a foot long.
I have seen my share of worms in my life but here everything is new to me. For example, there are long and skinny worms which build tubes out of mud and resemble sticks of bamboo – hence their common name: bamboo worms. Well, it took me a while to even figure out which end was the head and which the tail. And even after I had that sorted out, there was simply no easy way to identify them to genus and species. We have a few reference books for Antarctic marine invertebrate fauna, but they are far from complete. How could they be, considering how few scientists have the privilege to sample in these remote waters?
One of the weirdest worms I have ever seen is called Sternaspis (see image above). We commonly call them “butt worms” although I am not sure if you can find that name in any scientific reference. They are short and chubby and they have a double-shield at their hind end reminiscent of – OK, I’ll just say it – butt cheeks. Members of the genus Sternaspis also occur in other parts of the world but we will need genetic data to clarify whether the ones we find here belong to the same or a separate species.
And then there is Aphrodite, the Greek goddess of love and beauty. She has a whole family of worms named after her, Aphroditidae (see below image). They are certainly the biggest ones we’ve seen so far but they only show traces of their former beauty when we pull them up. Usually their backs would be covered with golden iridescent spines and scales, but, alas, they lose most of them on their journey to the surface. We can only imagine how seductive they must have looked crawling around in the deep.
Worms and other critters that live on the bottom of the ocean are called benthic. Some benthic species brood their offspring somewhere on or in their body. The juveniles are eventually released and look like their parents, only smaller. Since often neither juvenile nor adult move around much, the young usually continue to live close to their parents in a tight-knit little community. However, many benthic species will simply release their eggs and sperm into the water where they bump into each other, merge into one and develop into planktonic (= drifting) larval forms (which are being looked for under a microscope in the below image). The larvae look very different from their parents and they can drift around in the currents for weeks or months before they find a suitable place on the bottom to settle down and metamorphose into adults.
So, if we want to know how different populations of worms are connected to each other, it is important to understand their reproductive strategies and life cycles. Therefore, we also take plankton samples in addition to the benthic samples and look for larvae. So far, we’ve sorted through two plankton samples. We did find larvae of ribbon worms, sea stars and sea cucumbers, but no polychaetes yet. They have probably spotted our net, smelled trouble and found themselves a nice little current to get away… (did somebody say anthropomorphizing is bad?)
Contributed by: Dr. Anja Schulze, Texas A&M Galveston
28 Nov 2013 – First Sampling Day! (64o 24’S 61o 56’W)
For the midnight-to-noon crew, Thanksgiving began with restless anticipation of the first sampling event of this cruise. For me, this morning marked my very first Antarctic field work experience—something I’ve been anxiously awaiting since being offered the chance to come along on this adventure. Most of the other researchers on my shift are veterans, and may have been a little disappointed in the results of our first Blake trawl. The contents of the net were basically…mud. A giant sack of mud filled with (mostly) worms (see above image). And working up a net like the one we hauled in is time-consuming: all of the mud is carefully washed away, the water used for rinsing is sieved, and each rock is examined to prevent the inadvertent discarding of a rare individual or a species of particular interest to someone on board. By the end of my shift, my face was splattered with muddy seawater, my hands were a little numb, I was exhausted, and it felt wonderful. There’s something about working outside, being on a boat, and digging through mud to find critters that just feels like science. For me, nothing really comes close to the satisfaction that follows a day of field “work.” To call it work probably isn’t even fair—it really feels more like being 6 years old and exploring the creek in one of the parks in my hometown, in search of anything creepy-crawly. I feel so fortunate to have found an area of study that piques my curiosity and allows me to re-experience childlike wonder in the way that biology does. The excitement of seeing sea spiders, my organism of interest, emerging from the mud was a little unreal. Sea spiders are brooders; males carry around fertilized eggs until they are ready to hatch, and the young simply crawl away. One individual we picked from the trawl was covered with dozens of these mini-sea spiders, who seemed to be ready and waiting to stretch their eight little legs. It was a truly exciting find, and I’m looking forward to others like it.
This Thanksgiving, I’m so immensely thankful for this incredible opportunity I’ve been given: to tag along for 4 weeks of my favorite kind of “work” in some of the most beautiful environments on the planet (see below image). In the spirit of the holiday, I took a short survey of some of our team, asking them what they’re thinking about today. I’m sure we’re all thankful for our families, waiting for us to come home, but we’re also thankful for:
“Pilidia and ham, egg, and cheese sandwiches.”
“Our cook, Jerry, staying up all night so we could enjoy a wonderful Thanksgiving lunch.”
“Icebergs, penguins, and a smooth passage.”
“Our technicians and the science support staff that make our work possible.”
And, just because we can never be too thankful for our loved ones:
“The support of my family that allows me to take these trips.”
Happy Thanksgiving from our crew to yours!
Contributed by: Avril Harder, Graduate Researcher, Central Michigan University
27 Nov 2013 - The first day in Antarctica! (64o 52’ S 63o 46’ W)
The last 24 hrs were the most eventful so far. To begin with, we finally came to Antarctica, which you can physically sense by a noticeable reduction of the ship movements vs the Drake passage. Then it was a whole array of stunning landscapes with all imaginable combinations of ice and mountains, penguins and even leopard seals. Next we arrived at Palmer Station (see above image) – the US research base - small but a very efficient one and a very warm welcome. I had started with internet access after 4 days of relaxation and a ton of junk mails to be deleted. Then, it was a traditional shopping in a local store, a traditional bar with dancing, followed by non-traditional ‘hot tub’ for most of the party and, an even more untraditional jumping in freezing Antarctic water at 1am - only the bravest members of the crew and the research team did such a thing- the water temperature was really, really cold (-1oC!). In conclusion of our one-day Palmer adventure, we climbed a glacier (see below image) – another stunning and beautiful landscape on a very slippery slope indeed (I manage to get taste of an Antarctic water too J). Finally, the day is not over yet, we just sailed off the Palmer station and currently we are heading to our first sample collection this sunny evening with amazing mountains all around us. What a polar day!
Contributed by: Dr. Leonid L. Moroz, University of Florida
26 Nov 2013 – Nearing Palmer Station (64o 36.8’ S 62o 47.2’ W)
I woke up to the sounds of slush against the sides of our ship and thought, “Yeah, Antarctica! “ It felt like Christmas morning when I looked out my porthole and saw the ice. We are finally out of the Drake Passage and heading into the inner passage of the Antarctic Peninsula to Palmer Station (see above image). It only took eight days, two continents, two oceans and a Drake crossing to get here!
The changes over the past eight days are remarkable and quite dramatic; only last week, I started this trip under a gloomy blanket of grey, drizzling clouds in Seattle with a miserably decreasing photoperiod, Now the days are getting much longer as the “bottom” of the earth shows much of its face to the sun. Fairly soon, there will be no nighttime for us and even now there are only two or three hours of crepuscular light after 12 pm.
As the Gould passed through the Drake Passage (also known as Mar de Hoces), the ocean has changed dramatically too. The Drake is notorious for being the roughest body of water in the world. In terms of oceanography, this makes sense; the Drake is a relatively narrow passage between Cape Horn, South America and the tip of the Antarctic Peninsula, which is only about 800 km/500 m wide. So just as narrow water ways in rivers become rapids, so too the Drake becomes rough as the flow of three oceans, Pacific, Atlantic and Southern mix, intermingle and squeeze through a continental bottleneck. Add a bit of wind to that and you have incredibly rough waters. How rough? Well, there are many rumors from colleagues of being thrown from their bunks by the waves, but fortunately, I have no empirical evidence of any of this! Yes, it was rough enough to make it difficult to walk in a straight line, shower, put on pants, and eat dinner while holding down your cup and plate (don’t worry I didn’t try to do all these things at the same time) in the Drake, but apparently it can be far worse. I’ve crossed the Drake four times in one year and it’s been calm! Sailing lore and my colleagues, tell me I’ve been unbelievably lucky but we will eventually have to cross back in a month; I’ll be sure to give libation to Poseidon when we leave Palmer Station and start home.
Another dramatic change occurred between the start of the Southern Ocean and the end of the Atlantic when we crossed the Antarctic Polar Front (APF). I enjoyed watching the ships monitors as we passed through the APF; at lunch yesterday we were in 8C waters and by dinner we were down to 2C, a substantial change in temperature in a very short span of time for oceans. The APF marks a significant environmental change for organisms as well and is perhaps a barrier to their dispersal to islands and continental shelves considered sub-Antarctica. It is a unique result of the cold waters of the Southern Ocean colliding with all the world’s oceans.
The Southern Ocean and it’s predominate current, the Antarctic Circumpolar Current (ACC), or the West Wind Drift, isolates the entire Antarctic continent and shelf as it flows rapidly west to east. The ACC is generated by wind, the Coriolis Effect, and is confined to the area around Antarctica by deep oceanic basins as well as temperature and salinity differences between the worlds other oceans. Taken together these keep the Southern Ocean very cold and maintain the ice dome over the entire continent. So APF and ACC are one of earth’s exceptional boundaries.
We are only a few hours out of Palmer Station (see below image) where we will offload some scientists, tons of cargo for the station and boxes of fresh fruit and veggies, which I am sure the folks at Palmer will be glad to see! So soon we will start the adventure of collecting animals.
Contributed by: Dr. Megan Schwartz, University of Washington Tacoma