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).

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.

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!

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!

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.

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.

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.

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!

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.

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.

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.

The Adélie Penguin.

Data collected from Palmer Station and previous LTER cruises, among other sources, show a general decline of Adélie Penguin populations in the northern parts of the Peninsula, with a simultaneous increase in the size and numbers of colonies in the southern regions.

When it comes to humans, penguins can be very fearless and curious. Here, they look like they’re lining up to be taken back in the scientists’ zodiac!

With the decrease in numbers of Adélies, we have seen an increase in two closely related species, the Chinstrap and Gentoo Penguins, that breed mostly in the northern regions of the Peninsula. These penguins do not rely as heavily on winter sea ice for winter habitat as the Adélie Penguin does, and therefore can move into those areas the Adélies have abandoned. Every year on the LTER summer cruise we find more and more evidence of these trends in penguin population size and distribution.

Gentoo Penguins.

Baby and adult Chinstrap Penguins.

Even more surprising are recent sightings of species that have rarely, if ever, been seen as far south as some parts of our study region. For example, the King Penguin was seen on Torgersen Island in 2006 near Palmer Station, hundreds of kilometers south of its traditional breeding and feeding areas. In addition, the Macaroni Penguin was seen last season on Avian Island (the southern end of our study region,) over 400 km (~250 miles) further south than any of its kind have ever been seen before!

A nesting Macaroni Penguin.

King Penguins have a strong physical resemblance to Emperor Penguins, but, among other differences, are smaller in size. Photo by Mike Usher, courtesy of the National Science Foundation.

These unusual events are all fragments of the dramatic changes being foisted upon all creatures in this part of the world.

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.

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!

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!

The Western Antarctic Peninsula is one of the fastest warming places on the planet.

The moorings will remain in the water for one year and will be retrieved along with their data during the next LTER cruise. Each mooring is a line with attached instruments, held in place on the bottom with weights (cement blocks), and vertical in the water with floats or buoys. The moorings span a vertical distance of greater than 350 meters in the water and have a current meter and 17 temperature sensors that will monitor changes in water temperature. The current meter and temperature sensors will allow us to determine when warm, offshore water floods onto the continental shelf, bringing in heat and raising the ocean temperature on the shelf. The moorings will then monitor the decrease in temperature when heat is lost to the atmosphere (warming the air) and to the underside of glaciers (melting them). All of this information will help us learn how the ocean heat is partitioned into air warming and ice melting. One of the goals of this project is to help us understand why the western Antarctic Peninsula is undergoing the most rapid warming of air temperature in the winter on earth, and why 87% of the peninsula glaciers are in retreat (i.e., melting, and consequently raising global sea level).

At top right are all of the instruments that are used to monitor the changes described above strung out on the deck before deployment. These instruments can measure the speed and direction of water movement (currents), temperature, and pressure (depth). At bottom right, Fred Stuart (Electrical Technician, Raytheon Support) is seen preparing the acoustic release and current meter for deployment. At bottom left, Meghan King (Marine Technician, Raytheon Support) and Cooper Guest (Marine Science Technician, Raytheon Support) are seen ready to release the weights that anchor the mooring to the sea floor. The Palmer LTER would also like to thank the crew from the L. M. Gould for the support during the deployment and recovery of these moorings.