Ice Stories: Dispatches From Polar Scientists » biology http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 Going Under the Ice! http://icestories.exploratorium.edu/dispatches/going-under-the-ice/ http://icestories.exploratorium.edu/dispatches/going-under-the-ice/#comments Tue, 30 Dec 2008 18:13:47 +0000 Mark Krasberg http://icestories.exploratorium.edu/dispatches/?p=1425 SOUTH POLE STATION, ANTARCTICA– The day I arrived at McMurdo I ran into Ron Hipschman and John Weller. They told me they were going to go to the “Penguin Ranch” the next day, and I got permission to go with them. I was very lucky!

The trip was a roughly one hour ride over the sea ice in a dual-tracked vehicle called a MATTRAX.


Mount Erebus from the sea ice.

John Weller, our guide Peggy Malloy, Ron Hipschman and the MATTRAX.

During the trip we could see a few icebergs which were trapped in the sea ice.

What they do at the Penguin Ranch is study emperor penguins. They take a small number of emperor penguins from the coast and put them in a fenced in area on the sea ice. A couple of holes are cut in the ice for the penguins, and the penguins are then able to go swimming any time they want to (they catch their own food). The penguins apparently go diving around once an hour. There are no holes in the ice nearby, so the penguins always come back to the Penguin Ranch when they are done swimming.


Penguin Ranch.

The very beautiful emperor penguins.

A penguin at the start of a dive…

… and jumping back on top of the ice.

The best part of the Penguin Ranch was the observation tube. You can climb down in a narrow tube about 15 feet under the ice and look out some windows. The colors under the ice are amazing, as you can see! It was incredible to be under the ice and also to watch the penguins swimming.


Emperors swimming.

Thanks John and Ron and Peggy for a great day!

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Connecting Antarctic Science to Children http://icestories.exploratorium.edu/dispatches/connecting-antarctic-science-to-children/ http://icestories.exploratorium.edu/dispatches/connecting-antarctic-science-to-children/#comments Mon, 08 Dec 2008 02:25:38 +0000 Jean Pennycook http://icestories.exploratorium.edu/dispatches/?p=1269 CAPE ROYDS, ROSS ISLAND, ANTARCTICA– Most of the time while we are working with penguins in Antarctica, we are in the field at Cape Royds. We live in a tent and sleep on the ground near the breeding colony and it is a magical place for me. As far as we can see in any direction there is no sign of life except the penguins and us. Across 60 miles of frozen ocean is the Royal Society Range on the continent of Antarctica; we are on Ross Island frozen solid in the Ross Sea.


View of Cape Royds.

As a backdrop to our camp and the colony is Mt Erebus, a true living, breathing, belching, active volcano whose plume is only visible when the atmospheric conditions are just right.


View of Mt Erebus form Cape Royds.

Days will pass and we will not see another human being nor hear any sound other than our own and the birds. No, I do not get lonely, and I look forward all year to this two month time frame when I am given the gift of living at the edge of world with these remarkable creatures who adapted themselves to this harsh environment so they could have the place to themselves.

It is all about the science, and my job is connecting it to classrooms across the US and around the world, sharing the experience of Antarctica and the lives of these birds with children and others who may only see penguins in zoos. Many people do not have a sense of Antarctica and do not understand the role this large continent plays in our ocean and climate systems. Most will never set foot on this, the most remote place on Earth.

Many people do not realize how pristine and unspoiled the entire continent is. It is the only continent that has never been continuously populated by people, and except for the northern tip of the Antarctica peninsula, there are no land plants or animals above the micro level. The southern ocean that surrounds Antarctica is the last unspoiled ocean on the planet. If we are to maintain the unspoiled, untouched nature of this extraordinary place, people must have a connection to it and care about it. Our project reaches out to children and adults in an effort to create that connection and sense of stewardship.

Teachers in classrooms all across the country use our website to engage students about Antarctica. We have developed classroom activities, an educational DVD, webisodes, background information for teachers, and many activities designed to engage children in penguins, Antarctica and global climate change. One of our projects is about postcards. Many children have never received a piece of mail let alone a postcard from a foreign country, let alone a postcard from Antarctica. We have received and sent back over 10000 handmade penguin postcards from children around the world. Here are some examples.


Penguin postcards made by children.

Every year we select 6 breeding pairs (one from each pair is a banded bird) to follow along on a daily basis allowing children in classrooms a chance to be field biologists. They keep a field journal, recording the dates the eggs are laid, when the chicks hatch, how long the female or male is on the nest, how long the foraging trips are and other factors effecting the chicks growth. We hope some of these young biologists will make education and career choices that will propel them into the science and engineering fields. Here is an example of these nests from the beginning of the season to the end of the season.


Penguins on nests and chicks.

Other students connect with us by making a flag to fly at the research station.


This flag from students in Maine serves as a wind speed and direction indicator for our penguin cam.

A flag designed by a student flew on our research hut last year.

Some send us questions about penguins, Antarctica and the Polar regions, we have answered thousands.

We have also produced an educational DVD about how penguins are coping with global climate change. You can order a copy from our website penguinscience.com.

Yes it is about the science, and my job is to share that science with the world.
To see the webisodes visit http://www.penguinscience.com/media/video/webisodes.php.
To learn more about the postcard project, design a flag or other classroom activities visit http://www.penguinscience.com/classroom_home.php.

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Using Indigenous Plants http://icestories.exploratorium.edu/dispatches/using-indigenous-plants/ http://icestories.exploratorium.edu/dispatches/using-indigenous-plants/#comments Tue, 22 Jul 2008 21:07:54 +0000 Amy Breen http://icestories.exploratorium.edu/dispatches/?p=497 QUINHAGAK, ALASKA– Along with two elders and six students, I journeyed to a field camp near the Yup’ik village of Quinhagak last week. Dr. Kevin Jernigan, from University of Alaska’s Kuskokwim Campus, and I collaborated to co-teach a college-level class titled, ‘Introduction to Ethnobotany’.

The Yup’ik, the native peoples of the Yukon-Kuskokwim delta region, have lived at this site since at least 1,000 AD. The village is located at the mouth of the enchanting Kanetok River, on the shore of Kuskokwim Bay of the Bering Sea.


Our field trip to the Bering Sea coast to collect seashore plants.

What is ethnobotany? It is the study of how people of a particular culture use indigenous plants for provisions such as medicine, food, shelter and religious ceremonies. Botany, or the study of plants, forms the foundation for ethnobotany.

The aim for the course was to survey basic concepts of botany and ethnobotany, with emphasis on the native flora of Alaska and how people use these plants. I was paired with Kevin, an ethnobotanist, to introduce students to the fundamentals of plant biology and taxonomy (classification). My aim was to teach students to recognize regionally important plant families based on field characteristics and by using scientific keys. We also discussed methods of plant collection, including curation and ethical collecting concerns relating to plant conservation.


In the classroom, a student examines various plants representing common tundra plant families.

In the field, students collect tundra plants. The tundra is carpeted with an endless sea of the tufted fruits of cotton grass (Eriophorum russeolum).

In turn, I learned from Kevin the general principals of ethnobotany, including its history and importance in traditional and modern culture. We were fortunate to also be accompanied by two Yup’ik elders, Annie from Quinhagak and Cecilia from nearby Chevak. With their guidance, we discussed the cultural relevance of the native flora to the Yup’ik, as well as its traditional use for food and medicines.


Annie and Cecilia.

Although I was an instructor for the class, quite often I also played the role of learner. Not only did I learn from Kevin, I also learned from both the elders and students about their dependence upon the regional flora. Moreover, I quickly learned that I must adapt my university honed teaching philosophy. The class was taught in English, however the elders’ native language is Yup’ik. Furthermore, nearly every student was bilingual. Our discussions alternated between languages and required translation both to and from Yup’ik. I found this process absolutely fascinating.


Annie shares a beautiful bag constructed from a common seaside grass, or tapernaq in Yup’ik (Elymus arenarius).

On one occasion, I shared a plant with the class that Cecilia recalled from her youth. The plant, marsh five-finger (Potentilla palustris), is prevalent in wet tundra in western Alaska. She clutched the plant in her outstretched hand and asked quietly in her timid English, “Where did you find this plant?” I shared that I collected it nearby in the tundra surrounding the village. As she admired the plant, she shared her story about the marsh five-finger in Yup’ik. While the language was unfamiliar, her enthusiasm about and her high regard for the plant was apparent. I learned through translation that she remembered her grandmother collecting the plant when she was a very young girl. It was collected, dried, ground and drank in a tea as a substitute for coffee.

We had many similar plant encounters throughout the week; it was truly a dynamic learning experience for us all.


I was befriended by a local Yup’ik boy while I collected plants. He greeted me each afternoon with a bouquet of tundra plants. Usually, soon after I accepted his offering he shyly ran away.

My new friend with a twig from a felt-leaf willow (Salix alaxensis).
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Ross Sea Penguins http://icestories.exploratorium.edu/dispatches/antarctic-projects/ross-sea-penguins/ http://icestories.exploratorium.edu/dispatches/antarctic-projects/ross-sea-penguins/#comments Tue, 13 May 2008 00:58:53 +0000 Exploratorium http://icestories.exploratorium.edu/dispatches-new/?page_id=35 Studying how penguins respond to ecosystem change in Antarctica


Adélie penguins at Cape Crozier. Photo by Chris Linder, WHOI.
David Ainley

Biologist David Ainley of H. T. Harvey & Associates has been studying Adélie penguins in Antarctica for more than 25 years. These resilient, charismatic birds, adapted to survive one of the harshest environments on earth, are now being threatened by fisheries depletion and by global warming that affects the sea ice and ocean ecosystems on which they depend. David led a team of biologists who collected data about the changing demographics of Adélies breeding at four colonies, asking how resource availability affects whether or not birds emigrate from one colony to another. Studying how penguins respond to environmental changes—which are happening more dramatically at the poles than anywhere else on earth—will help scientists shed light on how species and ecosystems across the globe will be affected by climate and resource changes.

David Ainley and his team spread out to three different Adélie breeding colonies on the Ross Sea, Antarctica, in November 2008, and visited a fourth periodically. Learn more about the team’s research into Adélie breeding colonies—Cape Crozier, Cape Bird, and Cape Royds—through archived blogs and Webcasts from the team.

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The Microbial Loop http://icestories.exploratorium.edu/dispatches/the-microbial-loop/ http://icestories.exploratorium.edu/dispatches/the-microbial-loop/#comments Fri, 08 Feb 2008 14:06:49 +0000 Maria Vernet http://icestories.exploratorium.edu/dispatches-new/?p=69 The Microbial Biogeochemistry group (B-045) (under the direction of Dr. Hugh Ducklow) is one of the science groups here on board the LM Gould. Our goal is to study the bacteria that live in the water column and serve the important function of cycling elements such as carbon, nitrogen and phosphorous through the ecosystem. This process, referred to as the microbial loop, converts organic matter produced by the phytoplankton and zooplankton into inorganic matter that is used by the phytoplankton for primary production and/or photosynthesis.

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Corethron, a type of phytoplankton, highly magnified under the microscope.
phyto_corethronball2.jpgA ball of corethron, less magnified under the microscope.

At every station of the LTER grid the B-045 group takes water samples to analyze for dissolved gasses, dissolved organics and bulk bacterial parameters. The amount of oxygen in the water can give us an idea of the amount of primary and secondary production occurring in the water column. Dissolved organic carbon is also an important parameter to measure because it is the amount of material available for bacterial consumption. We directly measure bacterial production using radio-labeled amino acids, which shows the rate of carbon utilization by the bacteria.

In addition, we preserve samples to measure the amount of bacteria in each water sample. This analysis is done with the use of flow cytometry back at our home institution, the Ecosystems Center, MBL. We also do experimentation onboard involving molecular genetics to look at the diversity of the bacterioplankton community. In this process, we filter water to concentrate bacterial cells to perform downsteam DNA analysis.

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Our Microbial Biogeochemistry team. At top center, from left: Chip Cotton, Heidi Geisz, Erin Morgan, Aaron Randolph, and team leaders Matthew Erickson and Kristen Myers. At bottom center are images of the bacterial community, taken with a camera attached to a microscope aboard the vessel. At lower left, Aaron Randolph filters water to concentrate bacterial cells to perform downsteam DNA analysis. At lower right, Erin Morgan “pickles” a dissolved oxygen sample. At top right, Chip Cotton and Heidi Geisz inoculate a set of samples with the radio-labeled amino acid. At top left, an exuberant Heidi Geisz and Erin Morgan sample for dissolved organic carbon.

It has been a very successful and enjoyable cruise. While very busy the group has been able to enjoy several beautiful sunsets.

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Fun With Phytoplankton http://icestories.exploratorium.edu/dispatches/fun-with-phytoplankton/ http://icestories.exploratorium.edu/dispatches/fun-with-phytoplankton/#comments Wed, 30 Jan 2008 14:11:14 +0000 Maria Vernet http://icestories.exploratorium.edu/dispatches-new/?p=75 Today we will introduce you to the work of B016, the researchers here on the LTER cruise that study phytoplankton (microscopic plants.) This is the 14th year for the group! They study the plant life and measure how much carbon is made to feed bacteria, krill and hence whales and penguins – thus the basis of the food web.

The goal of the phytoplankton team is to understand phytoplankton ecology and physiology along the Palmer LTER grid in relation to environmental parameters such as water column stratification, sea ice, and light. A suite of measurements is obtained at different locations, starting with underwater light measurements with a Profiling Reflectance Radiometer (PRR).

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The PRR being deployed in the water.

Further sampling in the water is done based on what is learned about the light under the surface.

The B016 group samples up to 100 liters of sea water per day, or roughly 30 liters per station. Each liter of water is then filtered in order to concentrate the otherwise dilute phytoplankton for analysis. The water is also filtered for numerous measurements, one of which is pigment analysis by the High Performance Liquid Chromatography (HPLC.) Simply put, the HPLC determines concentrations of specific pigments present in the phytoplankton utilized by different taxonomic groups, and can thus lead to our understanding of the light absorption and group recognition of the phytoplankton population throughout the water column.

Anther important measurement taken by our team is the physiological status (think stressed or not) of the phytoplankton. In conjunction with group 0326, I work on the Fluorescence Induction and Relaxation System (FIRS) to measure stress levels in the phytoplankton.

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A colony of fluorescent chaetocerossocialis

The Rad-team conducts primary production experiments to determine the uptake of Carbon by the phytoplankton. The use of radioactive carbon allows the rad-team to measure the exact amount of carbon the phytoplankton incorporate into carbohydrates, via photosynthesis, in a 24-hour period.

We’ve assembled some pictures of our team below– enjoy!

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At top right is Scott Baker, helping pay out the PRR cable to a maximum depth of approximately 100 meters (about 300 feet.) At top left, Karie Sines filters the water. At bottom left, Wendy Kozlowski works on the HPLC machine. At bottom right, I work on the FIRS to measure phytoplankton stress levels. Second from top-right is the Rad-team, Diane Chakos and Katie Haman. Last but far from least, at second from topleft is Jeff, who not only filters tens of liters of seawater a day, but also keeps the 016 morning team well stocked with coffee, a necessity at 4:00 am! No explanation is needed for the bottom, middle picture: Team 016!
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Zooplankton Under the Microscope http://icestories.exploratorium.edu/dispatches/zooplankton-under-the-microscope/ http://icestories.exploratorium.edu/dispatches/zooplankton-under-the-microscope/#comments Sun, 27 Jan 2008 14:11:27 +0000 Maria Vernet http://icestories.exploratorium.edu/dispatches-new/?p=76 As you may have seen in one of our earlier dispatches regarding the zooplankton sampling methods (to read the dispatch click here) the zooplankton team scours the ocean with two nets, the smaller of which samples to a depth of 300 meters, nearly 1,000 feet below the surface (think of the Eiffel Tower standing between the net and the surface.) While the zooplankton group focuses on Antarctic krill (Euphausia superba, the largest and most abundant of the many species of crustaceans collectively called “krill,” a word that means whale food in Norwegian,) there are many other zooplankters we come across that also play an important role in the Southern Ocean ecosystem. One of the many strengths of the LTER program is the ability to look at long term changes in abundance (number and/or biomass) of these different species and the regional community composition (the relative amounts of each species.)

The LTER’s sampling grid covers inshore and offshore waters along the Antarctic Peninsula, where we see a broad range of organisms including jellyfish, squid, fish, salps, worms, and amphipods, among others.

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A ctenophore: a creature similar to jellyfish but without any stinging cells. These populate cold waters in both Antarctica and the Arctic.

One of our dissecting microscopes, used in the analysis of these organisms, is equipped with a digital camera that allows us to take pictures of what we see. We decided to compile some of our favorites here with the magnification for scale.

In the upper left is a pteropod called Limacina. Pteropods (a name meaning winged foot) are similar to snails and slugs, only they have wings and swim around in the ocean. Limacina swim with a bat-like flapping motion of their wings (the “chinchilla ears” in the photo). Also of note is their mucus net used in feeding; a single Limacina, roughly the size of the “G” on your keyboard, can cast a mucus net many times its size in diameter. This net traps phytoplankton until the Limacina consumes the net: algae, mucus and all. This architectural feat was discovered by blue-water divers watching pteropods feed in the ocean far from land.

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These closeups, taken through a microscope, are layered against a picture of the net tow being brought back aboard the ship.

At the top-center of the picture is a species of Protomyctophum, or Lantern Fish. The pearl-like spheres along its body are called photophores. Photophores are light-producing organs that typically line the bottom of a fish (though not only in fish, Euphausia superba has them too) in order to break up its silhouette, making it difficult for predators to identify them as prey.

In the middle of the picture is a very, very small starfish. To give you an idea of how small, the width of the forceps next to it is roughly 0.25 millimeters! This interesting pelagic (which is strange for the mostly bottom dwelling starfish) creature has shown up in two catches, hundreds of kilometers apart. None of us know exactly who or what it is.

The three pictures on the bottom are of a squid, a polychaete worm curled up next to a copepod (a small planktonic crustacean) and a group of Hyperoche amphipods. Amphipods are another group of crustaceans. This particular species is one of the more common amphipods found in the study. Note the large eyes! The squid and the polychaete, on the other hand, are rare finds. These photos offer a glimpse of the high diversity of small animals living in the Southern Ocean.

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Marine Mammals http://icestories.exploratorium.edu/dispatches/marine-mammals/ http://icestories.exploratorium.edu/dispatches/marine-mammals/#comments Thu, 24 Jan 2008 14:11:42 +0000 Maria Vernet http://icestories.exploratorium.edu/dispatches-new/?p=77 Each year on the cruise, we are privileged to have many encounters with marine mammals — mammals that live and feed primarily in the ocean. Mammals originally evolved on land and a subset later adapted to life in the sea. Unlike other marine life, marine mammals breathe air, rather than extracting oxygen from the water, they have hair (even whales have bristles!) and thick layers of fat under the skin called blubber to insulate their warm blooded bodies. Marine mammals also give live birth and rely on milk to feed their young — milk that is up to 50% fat in content!

At Palmer Station, we saw many Southern Elephant seals, which haul out on land this time of year to rest and molt their fur. Males, the larger of the genders, can get up to 21 feet long and weigh as much as 6000 lbs!

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Southern Elephant Seal (Mirounga leonina)

Elephant seals eat primarily fish and squid and have amazing eyesight adapted to deep diving, up to 1000 feet deep.

Leaving the Palmer area, we transited through many areas covered in icebergs and the remnants of last winter’s sea ice. We often spot seals and penguins lounging on these bits of ice, and this year were lucky to see two species of true seals (true meaning they have internal ears and are not jointed at the hips such as sea lions.)


A leopard seal (Hydrurga leptonyx) showing its teeth. Photo by Chad Rosenthal.

Leopard seals are a silver gray color with a serpentine head and huge masseter muscles. They are opportunistic foragers feeding on fish, krill, other seals and penguins.

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Crabeater Seal (Lobodon carcinophagus) Photo by Nicholas Metheny.

Though the name is deceiving, crabeater seals do not eat crabs; instead, they eat mainly krill. Like Adelie penguins, they are a sea-ice-dependent species found only in the Antarctic. Their teeth are beautifully cusped, acting as a strainer that retains the krill.

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Humpback Whale (Megaptera novaeangliae)

Though much larger – reaching at times 50 feet in length – the humpback whales also eat mainly krill and other plankton or small fish, straining out their prey with baleen. One method they employ to catch their prey involves spiraling up and down in dense schools of plankton which creates bubble nets that concentrate their prey. Individual whales are recognized by scientists by the unique patterns of black and white on their tail or fluke, like our fingerprints.

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Water Sampling http://icestories.exploratorium.edu/dispatches/water-sampling/ http://icestories.exploratorium.edu/dispatches/water-sampling/#comments Tue, 22 Jan 2008 08:12:33 +0000 Maria Vernet http://icestories.exploratorium.edu/dispatches-new/?p=80 Monday we reached the first station of the southernmost portion of the LTER grid and started the “200” line. We began sampling offshore at station 200.260 (“260” indicates that the station is 260 km from shore.) A major part of this procedure involved deploying and retrieving a deep CTD (Conductivity, Temperature, Depth) cast. The cast descended 3,694 m (about 12,005 ft!) to the seafloor, gathering information on the water column and capturing water samples from specific depths on its return to the surface.

The Gould’s crew did an excellent job positioning the ship and safely deploying the CTD’s carousel, a task made even more difficult by the foggy weather and large, rolling swell.

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The CTD carousel being prepared for deployment below deck.

Following the tradition of previous cruises, everyone had a chance to decorate a styrofoam cup and send it down to the depths! Each person received an 8 or 12 oz. styrofoam coffee cup, and drew colorful designs on the outside and inside using Sharpie markers. Many of these creative cups included information about the date, depth, and location of the cast, as well as pictures of “killer” zooplankton, miniature Goulds, Adelie penguins, and other Antarctic wildlife. The cups were collected before the cast and stuffed them with paper towels (to prevent collapse) then zip-tied into mesh bags that were affixed to the bottom interior of the CTD carousel.

As the cups descend, they are subjected to greater and greater water pressure. Pascal’s law (Pressure = fluid density * gravitational pull * height of water column) describes how pressure increases with depth. Basically, as an object sinks deeper in the water column it “feels” the weight of more and more water on top of it. Scuba divers use the following rule of thumb to determine pressure at different depths: 10 meters of water exert roughly the same amount of pressure as 1 atmosphere. In other words, a diver who is 10 m underwater experiences 2 atmospheres of pressure. This means that our styrofoam cups were under about 370 atmospheres of pressure at the seafloor!

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At bottom right, the creatively colored cups are stacked and ready to make the plunge. At top left, Heidi Geisz and Albert Kao stuff them with paper towels to prevent collapse and zip-tie them into mesh bags. At lower left, Meghan King ties the bags to the CTD carousel. At center, upper center, and upper right, you can see the result! At bottom center, Erin Morgan displays her cup for a “before” picture. To her right is the “after” picture, showing the shrunken cup next to a pen for scale.

As the cups sink, the water pressure squeezes the air out of the spaces in the styrofoam. This causes the cups to shrink to miniature size! In the upper right is the “angry zooplankton attacking the Gould” cup before and after descent into the depths. Shrinking also makes the colors very vibrant and beautiful!

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Penguins & Krill http://icestories.exploratorium.edu/dispatches/penguins-krill/ http://icestories.exploratorium.edu/dispatches/penguins-krill/#comments Fri, 18 Jan 2008 14:13:31 +0000 Maria Vernet http://icestories.exploratorium.edu/dispatches-new/?p=83 Hello from the Frozen South!

Though we are currently around 200 km off shore, a few days ago we had a beautiful day to bob inshore and drop two Zodiacs in the water. The bird ecology crew was off first with a team of folks headed for the Armstrong Reef islands where Adélie penguins maintain breeding colonies. Meanwhile, our zooplankton ecologists zoomed through the reef waters in search of krill using sonar coupled with a trawl net.

The primary focus of the seabird work on these islands is the Adélie penguin (Pygoscelis adeliae) foraging ecology as relates to breeding success. Seven of the islands in this group have been surveyed for the last 5 years, including a census of breeding adults and chicks.

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Young male Adélie penguins compete with each other for female attention.

Though the Zodiac is securely tied to the shoreline, the best practice is to make sure all the survival gear comes ashore with the group. Each pair of adult Adélie penguins lays two eggs in early November and will try to raise two chicks. Variability in breeding success is due to direct physical factors, such as annual snow fall and/or winter sea ice extent and duration, which also tie into biological factors such as food availability (fish and krill). The second portion of this study involves examining the penguin diets in this area. We generally find the nutrition of these Adélies dominated by Antarctic krill (Euphausia superba).

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At top left, Raytheon Polar Services crew crane the Zodiac off the L. M. Gould. At bottom left, Langdon Quetin, a principle investigator for the krill group, steers the krill rig. At top right, the bird group sets up for census and diet work on one of the islands. At center far right, Whitney Wilkinson prepares to process the krill haul. To her left, an adult Adélie penguin looks on at a gray Adélie chick. At bottom middle, the birders pose for a picture near a cliffside Adélie colony at the end of the day, while at bottom right, both small boats head back to be loaded onto the LMG by the low light of a midnight sunset.

Our zooplankton folk spent the day looking for schools of krill between the islands of the Armstrong Reef. This study also examines foraging ecology, but the foraging or grazing of krill. Just like cows graze grass, krill graze phytoplankton and ecologists examine the ingestion rates of these animals using grazing experiments. Early in the day, the only animals to be found were too small for experiments. However, the payload run arrived the last attempt of the day, thus our krillers were successful in their ventures.

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