Sadie here with a brief expedition update and a look inside shipboard lab operations! The next island along our route was Agattu, but inclement weather forced us to head East sooner than expected. After a full travel day, we arrived at beautiful Kiska Island this morning. As usual, the Edwards Lab dive team deployed chambers in three different habitat types (kelp, transition, and urchin barren). A quick refresher on what our lab is doing up here in the Aleutians: we’re comparing ecosystem productivity between these three habitats and among different islands in an east-west gradient along the island chain. For this large-scale project, we use clear, flexible chambers to isolate 0.57m^2 patches of the seafloor for 24-hour periods, meanwhile collecting changing oxygen concentration, temperature, and light data within these chambers. The organisms in nearshore benthic habitats all use or produce oxygen during photosynthesis or respiration, so we use oxygen concentration to assess the activities of algae and animals within the chambers. These data help us estimate productivity from the community as a whole; however, we want to go deeper into the story! Algae and invertebrate animals from inside the chambers are collected and brought back to the ship and further analyzed to help us understand how individual members of the community are contributing to our large-scale production estimates. That’s where Dr. Ju-Hyoung Kim and I come in. We’re using small-scale methods at the individual level to add details to the large-scale benthic chambers that give us community-level data. In the shipboard laboratory, we have set up small glass incubation chambers that hold one organism at a time. By controlling temperature and light, we can measure the change in oxygen concentration via photosynthesis (algae) and respiration (animals). Coupled with biomass data from the chambers, we hope tease apart how each species contributes to the larger productivity estimate within the benthic chambers that the dive team deploys in the field. These experiments in the field and in the laboratory allow our group of scientists to come together and work toward a common goal, which is to understand more about the valuable ecosystems of the Aleutian Islands! Usually our common goal is research-related, but sometimes we get together and make algae art! Featured here in an herbarium pressing: Neoptilota asplenoides, Kallymeniopsis sp., Odonthalia setacea, Neinburgia prolifera, Callophyllis sp., and more. Catch you at the next island!
--SS
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Nizki Island 7/14/2017 Hey there, this is Pike coming at you again from the Semichi Islands. Another day, another deployment. We’ve been in the Aleutians aboard the r/v Oceanus for just over a week now, diving in frigid water almost every day now. After trawling on Attu, we began our steam eastward; in the pre-dawn gloom we “dropped hook” in a small island cluster known as the Semichis. As we stumbled out of our bunks and towards the galley, following the smell of breakfast and hot coffee, a peculiar sight caught my attention; lights in the distance. Deceived by a brain still half-asleep, it took me a minute to process what I saw. Since leaving Adak the last week the only signs of humans we’ve seen have been remnants of WWII and the flotsam that’s washed up on the beaches. Here, in one of the most remote places on the planet, we hardly expect to see another living soul. And yet, what looked like a small city twinkled persistently on the horizon. As the sky began to lighten I realized what we were seeing; the military base on Shemya. During the Cold War the US built a top-secret radar station here, and to this day the ominous “boom box” still listens for ballistic missiles, should they enter US airspace. But we’re not here in the Semichis to gawk; we have our experiments to deploy and samples to collect. As stated before, the benthic productivity chambers (three in each of three habitat-types) are a beast to deploy. It takes all five divers from the Edwards Lab to set them up; we use lengths of heavy chain and whatever rocks we can find to make sure our chambers, and their respective sensors, stay upright all through the day and night. For those of you that might have missed it, inside each chamber we mount an oxygen and temperature sensor and a PAR sensor. PAR stands for “photosynthetically active radiation” or, more simply, the specific part of the light spectrum that plants and algae use for photosynthesis. The productivity chambers allow us to gain an understanding of what’s going in a fixed volume of water, which is important when we go to calculate the overall productivity of a system. What do we mean by productivity? We’re essentially looking at the difference between production (measured in the amount of oxygen produced) and respiration (the amount of oxygen consumed). Plants (and algae of course) and animals respire, but only photosynthesizers produce oxygen. Once we have a measurement of oxygen produced/consumed inside the chambers, we can compare that to the data gathered by the sensors we leave outside of the chambers, which are recording what’s going on in the environment. At the end of the 24-hr deployment, we “ground-truth” our measurements by collecting all of the organisms inside of the chambers when we go to pick them up and measure their biomass aboard the Oceanus. All the while we’re at sea, diving and steaming between islands, a colleague from Kunsan National University in Korea, Dr. Ju-Hyoung, and another Edwards Lab member, Sadie Small, run on-board experiments so we can get measurements on individual species’ rates of oxygen consumption/production.
Alright, I think that’s enough ecology for today. Be sure to check back in, after the Semichis we’re heading east again towards yet another island. Until then, this is Pike (aka Baron von Urchin) checking in from the Aleutian Archipelago Attu Island 7/12/2017 “This isn’t the end of the world, but you can see it from here” These words are posted on a sign at the US Coast Guard outpost on Attu. This lonely but spectacular island is the furthest west you can go in North America; technically we’re closer to Russia than anywhere else. Attu saw a severe battle between the US and entrenched Japanese soldiers during the second World War, but you’d never know it by the vistas afforded to us from our anchorage in Holtz Bay. Most of us, at least from San Diego, were eagerly awaiting our time at Attu. What would it be like all the way west? Would the wind be howling across the Near Strait? Would the water be unbearably cold? What would the rocky reef communities look like? Attu, if nothing else, was spectacular beyond belief. Our dive sites were in the three different habitats that we are studying: a kelp forest, an urchin barren, and a transition zone. The conditions were exemplary and each midnight sunset was more spectacular than the last. The wind howling through hidden glacier-carved valleys subsided as we launched the small boats to our dive sites. The sun showed itself on multiple occasions, revealing towering snow-capped peaks looming above us. Tussock grass swayed gently in the breeze on the cliffs as murrelets and puffins darted between the water and the sky around us. Deployment of the benthic experiments went smoothly. We put three benthic chambers in each habitat to measure how much oxygen each habitat is producing. We may expect that kelp forests, because of the abundance of photosynthetic material (ie kelp) in the habitat, are more ‘productive’ ie produce more oxygen than urchin barrens, which are mostly devoid of kelp. Once they are placed on the bottom they sit for most of the time, although we maintain them every six hours, which affords us time to work on other projects. In the meantime, we enjoyed the sites Attu had to offer with breathless amazement. We were even allowed on shore for a brief expedition. But, all too soon we had to pack up our experiments, stow the small boats on the Oceanus’s deck and begin our steam back east. For the rest of the trip we’ll be running to several more islands as we make our way eastward to Dutch Harbor on Unalaska, and our departure from the Aleutians.
Until next time, -Pike (aka Baron von Urchin) Tristin here, greetings from the Aleutian Archipelago! This week we embarked on our lab’s second voyage to the Aleutian Archipelago to study patterns of biodiversity and ecosystem functioning along the island chain! Our lab was granted NSF (National Science Foundation) funding for a two-year study how biodiversity and ecosystem production have changed following wide-spread kelp loss. We are focusing on three habitat types: Kelp forests, Urchin Barrens, and areas that are in transition between the two. Last year, we traveled from Adak (center of the Aleutian Island chain) towards mainland Alaska. That 21-day cruise on the R/V Oceanus covered a 444-mile expanse, and we surveyed six islands. For a more information on our research goals, and history of the project scroll down to the “Welcome to the Aleutian Islands Blog 2016” at the bottom of this page. This year, we will expand on the work we did last year and sample the far western Aleutians including the islands: Amchitka, Kiska, Attu, Agattu, and Shemya. The furthest of the islands is Attu (see image), and to put it in perspective, Attu is 1,100 miles from mainland Alaska… and ~450 miles to Russian territory. As a side-note and interesting fact, during WWII, Attu was the only battle fought on American soil. The expanse of our trip this year will lake us west from Adak to Attu, then back east where we will end our cruise in Dutch Harbor, AK. Team Edwards (Dr. Matt Edwards, Dr. Ju-Houng Kim, Scott Gabara, Tristin McHugh, Sadie Small, Pike Spector and Genoa Sullaway) is back in action, and we are ready for another amazing adventure. Stay tuned for more updates on our research activities over the next couple of weeks! Genoa here! We just left Amchitka Island and are en route to Attu Island, however it will take us about 21 hours to get there, and we have to steam through Buldir Pass which is a section of exposed Bering Sea...Needless to say we are taking our seasick medicine now! At Amchitka Island we were anchored next to an old World War II pier and one of our dive sites was littered with bullet casings and an old airplane wing! We need to get back to sorting samples so not much time to write, but here are a few pictures from the island! R/V Oceanus anchored in Constantine Harbor, Amchitka Island. It may be cloudy on the surface, but underwater, the subtidal world shows off its vibrant colors. In this photo the Dragon kelp (Eularia fistolusa) sporophylls (reproductive kelp blades) are surrounded by hungry sea urchins. Often, kelp can survive on pinnacles like this because the water speeds up as it goes over the rocks and knocks off the hungry urchins. Additionally, the sporophylls are strong and as they sway back and forth in the wave motion and knock off the sea urchins. But kelps that aren't lucky enough to grow on tall rocks or pinnacles lose their defense from hungry sea urchins. View from the bridge of the RV Oceanus as we steam through Buldir Pass on the foggy Bering Sea.
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