A black-browed Albatross observed during our at-sea surveys along the LTER sampling grid. (Photo by K.B. Gorman)

 This includes species with extremely high biomass or critical conservation interest such as the Adelie penguin or the southern giant petrel.  These animals occupy specific ecological niches and depend on ocean productivity for their own survival as well as for raising their young.  Hi, I’m Bill Fraser and my team and I conduct at-sea observations of seabirds during the cruise to identify the importance of foraging locations.  
One of the highlights of our work on the LTER cruise is the 5-day field camp at Avian Island, just off the southern tip of Adelaide Island in Marguerite Bay.  Here, we are interested in aspects of the breeding and foraging ecology of these species in comparison with lower latitude nesting areas around the Palmer Station.  We try to assess the variation between populations that are subject to different environmental conditions from

Sunset over Avian Island showing the large numbers of nesting Adelie penguins. (Photo by K.B. Gorman)

climate warming.  We typically census nesting Adelie penguins, southern giant petrels and blue-eyed shags, as well as deploy satellite Platform Terminal Transmitters (PTT).  These PTT’s are instruments we attach to adult Adelie penguins to track foraging areas used by the adults to obtain what nutrients they use to feed chicks.  

A PTT transmitter attached to an adult Adelie penguin with chicks at Avian Island. (Photo by K.B. Gorman)

This year was exceptional in that we explored the presence of nesting Adelie penguins at Charcot Island, an area even farther south than Avian Island that is still subject to the presence of summer sea-ice.  We were able to confirm the presence of Adelies in the area, and despite the moderate sea-ice able to access the colony to attach PTT’s to nesting adults.  This is the most southern population of Adelie

Charcot Island in sea-ice where we searched for nesting Adelie penguins. (Photo by K.B. Gorman)

penguins our group has worked with to date.  The data obtained from Charcot Island will lend an unprecedented perspective on the foraging ecology of this sea-ice dependent species.

This is a view of Charcot Island from about 4 miles away through the sea ice, with tabular bergs in front of the island. (Photo by Alex Kahl)

We are at Charcot Island, 69 deg 48 min South, 75 deg 30 min West.  This Island is 30 miles long and 25 miles wide.  It is the farthest south the LM Gould has ever been!   As you know we have come this far south in search of a place that is cold enough for sea ice to be present during this summer season.  But also, because we are searching for a poorly-documented Adelie penguin colony here.  Yesterday we entered sea ice around noon and then we were able to get close enough to the island by Zodiac to visually and photographically verify the presence of penguins.

Tabular Iceberg near Charcot Island (Photo by: Alex Kahl)

These first two pictures are calved off ice shelves – hence their very regular shapes and height.  Subsequently, the larger part of the berg that is underwater, gets melted and eroded by wave action and the bergs overturn and assume fantastic shapes.  The many tabular bergs near Charcot Island may be remnants of the Wilkins Ice Shelf, parts of which disintegrated in early 2008.
 

Tabular Iceberg and the LMG taken from our zodiac (photo by Alex Kahl

Take a closer look at the tabular ice berg and see if you notice the coloration.  The sea ice is colored this way from specially -adapted organisms like sea ice diatoms – a phytoplankton that live in brine channels in the ice.  Growth of these algae in the spring colors the ice tan or brown.  The color is not dirt but rather a rich biological community.
 

Diatoms in the Ice (Photo by Maggie Waldron)

http://en.wikipedia.org/wiki/Adelaide_Island

One of our gliders deployed from our zodiacs on January 19th and is now swimming toward Adelaide Island.  The data from the glider will survey the area where penguins like to feed and then provide us information on the biological and physical conditions of the water there.  You can follow the gliders progress on the web (RUCool).  You will see the Palmer LTER glider called RU05 at this link and find out more about the information it is collecting.  
Gliders combined with feedback from the moorings will provide us a foundation for an ocean observing network that gives scientists, like me, a view of the Southern Ocean near the Western Antarctic Peninsula 365 days a year.  This will be critical to understanding how changes in climate will influence the biology of the water surrounding Western Antarctic Peninsula.  
I’ve

Data Provided by John Kerfoot

included an example of some data collected during this January 19th deployment.  The colors show the magnitude of what variables we are measuring.  In this case I’ve shared temperature data and phytoplankton data collected by the glider.  The bottom panel shows the ocean temperature recorded by the glider as it travels (distance) at different depths (meters).  How cold is the water at depth?  The top panel shows a map of phytoplankton, which if you notice is growing well in the upper ocean layers.  Why do you think so? Well, this is where  sunlight is capable of driving photosysnthesis (the food making process for plants).  The white gaps in the data is where the glider has gone to the surface and is making a cell phone call to New jersey.  (Data graphic provided by John Kerfoot)

The Webb glider being deployed from a zodiac on January 19th, 2009 (Photo courtesy Elizabeth Leonardis)

We have added these robots to Palmer’s oceanographic field studies because they have many advantages over working from a ship.  They can be deployed in the water for several months at a time depending on the type of batteries we use.  They are mobile and we can change their sampling patterns as the ocean changes.  But better yet, they do not get sea sick which allows us to collect data during harsh conditions that often are unsuitable for us working from a back of a ship.  The glider does not have a propeller.  Instead, it moves by changing its buoyancy.  The robot is carefully balanced so that it maintains a neutral buoyancy, changing its weight by sucking in a small amount of sea water to make it float or sink.  It is equipped with wings, which make it move forward as it sinks.  When it reaches its desired depth,  it pushes the sea water out of its ballast, making the glider lighter than water which forces it to float upwards in a forward direction.  This is very efficient and allows the glider to “fly” around for months at a time.  

A Webb glider resurfacing. In the background is the Lawrence M. Gould. (Photo courtesy of Elizabeth Leonardis)

Every so often, the glider stops at the surface and makes a global cell phone call back to my lab at Rutgers University.  During this time scientists in New Jersey download data and adjust where the glider is moving.  The glider carries with it several sensors.  One is the Conductivity-Temperature-Depth (CTD) sensor.  Another is a sensor which measures the optical properties in the ocean water, which scientists can relate to the amount of phytoplankton and particles present.