Vessels Archives for NBP
Posted October 19, 2012
The research vessel Nathaniel B. Palmer is currently idle at Punta Arenas, Chile, with no expeditions planned until early December. Its last voyage was in August in support of NOAA’s Antarctic Marine Living Resources (AMLR) program, which monitors the effects of commercial fisheries on the ecosystem.
This was the first wintertime survey of the South Shetlands region, focusing on the Elephant Island portion of the Southern Ocean monitored by the AMLR program, which is managed by NOAA’s Antarctic Ecosystem Research Division .
The survey also represents a new collaboration with the National Science Foundation’s Office of Polar Programs , which supported the AMLR research with 18 ship days aboard the Palmer. Studies focused on zooplankton, pelagic fish, and oceanographic features in open water and ice.
Posted May 18, 2012
Scientists aboard the research vessel Nathaniel B. Palmer wrapped up a five-week-long cruise to the eastern side of the Antarctic Peninsula in April.
The LARISSA (Larsen Ice Shelf System, Antarctica) project is studying the response of the marine ecosystem to a series of ice shelf breakups that started in 1989 with the final disintegration of the Larsen A Ice Shelf. The Larsen B Ice Shelf shattered in 2002.
In the first week of April, the Palmer found maneuvering through the thick sea ice challenging as the various science teams took samples from the seafloor all the way through the water column. It took the ship two days to move 30 nautical miles along the northern portion of the Larsen A embayment to reach its final sampling station. Snowy conditions and low visibility impeded navigation several nights.
The second week of what was proving to be an unusually cold month was spent traveling through heavy sea ice from the northern Larsen A to the tip of the Antarctic Peninsula. The heavy sea ice forced the researchers to abandon a series of planned activities.
The ship was able to recover one of the whalebone landers that had been deployed two years ago in Antarctic Sound. The device is a rectangular frame with baskets on either side that hold whalebones. The whalebones are a way to look at the biodiversity on the seafloor as various organisms colonize the habitat. The scientists also recovered a couple of additional sediment cores before heading north to Punta Arenas, Chile, to end the expedition.
Posted April 5, 2012
The research vessel Nathaniel B. Palmer left Punta Arenas, Chile, on March 11, just in time to miss the fallout from a massive storm that caused widespread flooding in the country’s southernmost town.
The ship set out on a five-week expedition in support of the LARISSA project, for Larsen Ice Shelf System, Antarctica. This is the second major research cruise for LARISSA, an interdisciplinary program to study as many facets of an ice shelf ecosystem as possible following the collapse of the Larsen B Ice Shelf in 2002. [See previous Antarctic Sun series on LARISSA.]
The researchers want to understand the conditions that led to the disintegration, looking not only at the more immediate evidence, but traveling back thousands of years in the region’s climate history to determine if the event was part of a longer natural cycle or an aberration caused by the extreme warming now under way along the Antarctic Peninsula.
Photo Credit: Amber Lancaster/PolarTREC
An instrument called a megacore, which collects sediments from the seafloor, is lowered onto the deck of the NBP.
Other scientists on the project want to look at an ecosystem that existed under the shadow of the ice shelf before it collapsed, and how the absence of the shelf is now changing the local biology and ocean properties.
During the 2009-10 season, carrying two helicopters and a shipload of some of the Antarctic’s leading scientists, the Palmer attempted to penetrate through the sea ice that choked the eastern side of the Antarctic Peninsula.
But the ship never got close to the edge of the remaining ice shelf. Instead, it retreated to the western side of the peninsula and conducted a variety of experiments, though glaciologists were able to launch across the spine of the mountainous region to set up observatories. Another group, separate from the ship contingent, successfully drilled an ice core from the peninsula. [See previous article — Change of plans: Stiff sea ice forces LARISSA science cruise to reassess project priorities.]
This year the ship is returning to revisit previous study sites on the western side of the peninsula, as well as make another attempt to reach the Larsen Ice Shelf.
The first item on the agenda was the recovery of the so-called “whalebone lander,” a rectangular frame with baskets on either side that hold whalebones. It was left on the seafloor during the previous LARISSA cruise. Apparently, whalebones are one way to look at the biodiversity on the seafloor as various organisms colonize the “tasty” habitat.
Follow along with the current research cruise at two different blogs. Amber Lancaster, a teacher from San Francisco participating in the PolarTREC program , is posting updates at http://www.polartrec.com/expeditions/impacts-of-the-larsen-ice-shelf-system-on-the-weddell-sea . Scientists and students at Hamilton College are also blogging about their experiences and research at http://www.hamilton.edu/expeditions/antarctica-2012 .
Posted February 17, 2012
The research vessel Nathaniel B. Palmer had only been in the Ross Sea for a few days in support of a major study on the effects of iron on the chemistry and biology of the Southern Ocean before it had to temporarily suspend its mission to aid a ship in distress.
Photo Credit: Corey Chan/Antarctic Photo Library
The NATHANIEL B. PALMER at McMurdo Station in February 2012.
A fire aboard a fishing vessel on Jan. 10 forced the crew to abandon ship, killing three and injuring seven. The Palmer arrived on the scene in about 16 hours, taking the injured aboard and transporting them to McMurdo Station , where they were flown to New Zealand for treatment. [See previous article — To the rescue: USAP research vessel transports victims of ship fire to safety.]
About 48 hours after the adventure began, the Palmer returned to the Ross Sea to continue its cruise in support of project called Processes Regulating Iron Supply at the Mesoscale , or PRISM. The mesoscale refers to ocean features that are a few tens of kilometers in size.
Iron is linked to the growth of phytoplankton, very tiny, free-floating organisms that form the base of the polar marine food web. Scientists believe that iron is the main limiting factor for phytoplankton growth in the Southern Ocean.
The investigations included visits to the Ross Sea polynya, an area of open water in sea ice off the coast, as well as to the Ross Ice Shelf. The cruise was scheduled to finish in early February, with the Palmer docking at McMurdo Station.
Posted January 27, 2012
In late December, the research vessel Nathaniel B. Palmer went on a six-week cruise in search of iron, steaming from Punta Arenas, Chile, with plans to arrive at McMurdo Station in February.
No, this isn’t some rouge grab for resources in the Southern Ocean. The researchers are interested in assessing the sources of the trace metal for a project called Processes Regulating Iron Supply at the Mesoscale , or PRISM. The mesoscale refers to ocean features that are a few tens of kilometers in size.
Photo Credit: Dave Munroe/Antarctic Photo Library
Water spills over the stern of the PALMER during a storm.
Nearly 30 researchers, studying the biology, chemistry and physics of the ocean, are participating in the cruise, led by chief scientist Dennis McGillicuddy from Woods Hole Oceanographic Institution .
Iron is linked to the growth of phytoplankton, very tiny, free-floating organisms that form the base of the polar marine food web. Scientists believe that iron is the main limiting factor for phytoplankton growth in the Southern Ocean.
Thirteen days passed before the ship reached its first sampling sites in early January, where scientists will use many techniques and instruments to measure iron supply and sources.
The first experiment will involve taking samples from three sites, two outside an area of sea ice and one right in the middle of ice concentration. The researchers hypothesize that melting sea ice is a source of iron to near-surface waters. They believe that iron accumulates in sea ice as atmospheric dust particles are deposited on it as it sits on top of the water, according to the STEM in Action blog that is following the expedition.
The project’s ultimate goal is to understand how the marine food web in the Ross Sea and other parts of Antarctic works.
Posted December 9, 2011
The research vessel Nathaniel B. Palmer set sail about mid-November in support of ongoing research led by Teresa Chereskin , a scientist with Scripps Institution of Oceanography at the University of California in San Diego .
Photo Credit: Dave Munroe/Antarctic Photo Library
The bridge of the Nathaniel B. Palmer is covered in ice during a research cruise earlier this year.
This is the fifth and final year of the oceanography project to study the world’s largest ocean current, the Antarctic Circumpolar Current (ACC), while cruising around the Drake Passage, an infamous stretch of water between South America and Antarctica. The Drake Passage is an ideal spot to study the ACC, in part, because it’s a chokepoint where the current narrows.
Over the years, the research team has put out a moored array of instruments called CPIES (Current-and-Pressure-recording, Inverted Echo Sounders), which record oceanic data that are collected from the ship via acoustic telemetry, leaving the instruments undisturbed until recovered.
This year, the researchers plan to recover 45 CPIES at 44 sites in the Drake.
Posted November 11, 2011
The research vessel Nathaniel B. Palmer continued its seven-week cruise in support of chief scientist Nerida Wilson, with Scripps Institution of Oceanography , whose team is studying the connectedness between marine species from South America and Antarctica.
Photo Credit: Lt. Philip Hall/NOAA Corps
Elephant Island, one of study sites for the research cruise.
The expedition is cruising along the Scotia Arc, a stretch of the Southern Ocean comprised of submarine ridges and several island groups where two tectonic plates meet. The researchers want to understand how the Scotia Arc may connect populations of benthic marine invertebrates that are found from South America to Antarctica. They’re also studying the idea that many of these species occur around all of Antarctica.
Weekly reports from Wilson say the expedition is going well, having carried out 82 sampling events and taken more than 8,500 photographs of sampled specimens, as of Oct. 22.
Fishing for specimens was difficult mid-month, as sea ice and wind made trawling difficult to direct, and numerous rocks damaged nets. However, after some modifications, the wear and tear on equipment eased. The next week the nets held while the ship collected organisms around Discovery Bank, the South Orkneys, and one Elephant Island site.
The Palmer is scheduled to return to Punta Arenas, Chile, on Nov. 5.
Posted October 7, 2011
The research vessel Nathaniel B. Palmer pulled out of Punta Arenas, Chile, in mid-September on a seven-week cruise in support of a project studying the connectedness of marine species between South America and Antarctica.
Specifically, the expedition will cruise along the Scotia Arc, a stretch of area comprised of submarine ridges and several island groups where two tectonic plates meet. The research team, led by scientists from the University of California-San Diego’s Scripps Institution of Oceanography , is investigating the role that the arc plays in connecting populations of benthic organisms between the continents.
Photo Credit: Jeff Scanniello/Antarctic Photo Library
The research vessel Nathaniel B. Palmer docked at the ice pier McMurdo Station at the end of the last summer field season.
The researchers will collect seafloor critters from a variety of locations to address hypotheses regarding speciation and connectivity, to estimate demographic population changes, and to identify the underlying processes that drive observed phylogeographic patterns, the study of the historical processes that may be responsible for present-day geographic distributions of individual organisms.
“Comparative phylogeography is a particularly valuable approach because it enables the identification of long-term barriers and refugia common to groups of species and is consequently highly relevant to conservation planning,” wrote chief scientist Nerida Wilson in the first week’s ship report. “Moreover, this work will form a valuable baseline for detecting future changes in connectivity.”
The first stop for the Palmer was Shag Rocks, a small group of six sub-Antarctic islands. To capture the seafloor critters for the project, the crew deployed baited crab pots and conducted Blake trawls, which employ a heavy frame attached to a net to scoop up organisms from a small area of seafloor.
The trawls, made at depths of about 180 meters or less, were particularly successful during the early days of the project.
Posted June 24, 2011
The research vessel Nathaniel B. Palmer recently completed a five-week cruise to collect deep-water corals across the Drake Passage and Scotia Sea, including the Argentinean and Antarctic continental shelves.
The research cruise, led by Laura Robinson from Woods Hole Oceanographic Institution and Rhian Waller at the University of Maine , collected the corals and other benthic-dwelling organisms at depths of more than 2,000 meters.
The samples, when combined with imagery and mapping, will help the researchers reconstruct conditions in the Southern Ocean during the last glacial maximum about 20,000 years ago, and the subsequent deglaciation. The skeletons of deep-sea corals (live and fossilized) can record information on past climate.
Photo Credit: Laura Robinson/antarcticcorals.blogspot.com
Scienitsts sort fossils collected from dredges around Cape Horn.
The data will also help the investigators understand the past and present biogeography of corals in the Drake Passage.
The Southern Ocean is particularly sensitive to climate change, which means that fauna like the corals may experience large-scale changes to their environments, Robinson reported in a weekly science report from the ship. Carbonate organisms are at risk from ocean acidification, and deep-sea corals are a group that is likely to be particularly vulnerable.
“However, our understanding of how climate change may affect the distribution and health of cold-water corals is inadequate and improving this understanding is a concern for conservation efforts,” wrote Robinson, chief scientist during the cruise.
The research is a continuation of a pilot project in 2008 during which scientists aboard the Palmer located, mapped and collected deep-sea corals in the Drake Passage.
Overall, the latest cruise was a success, with sampling in six separate areas across the Drake Passage, Robinson reported. Samples will be transported back to the scientists’ laboratories for further analyses.
For more on the project, check out the expedition blog, Corals in the Drake Passage .
Posted May 6, 2011
The research vessel Nathaniel B. Palmer pulled into port at Punta Arenas, Chile, near the end of April, marking the completion of a two-month expedition that started at McMurdo Station .
The cruise was actually the ship’s third mission since it originally left Punta Arenas on Oct. 23, 2010. The first expedition focused on studying the physical ocean properties of the Amundsen Sea polynya, an area of open water in the sea ice that has shown high levels of biological activity. [See previous article: Aspiring for knowledge.]
That research cruise ended at McMurdo Station, followed by a second, month-long expedition to the Ross Sea, led by chief scientist Josh Kohut from Rutgers University . The scientists were interested in learning about the phytoplankton at the base of the Ross Sea’s food web and the special combination of currents, nutrients, and trace metals that allow it to thrive.
The latest cruise, led by Jim Swift of Scripps Institution of Oceanography , was at sea for more than 60 days, using a variety of instruments to collect water samples to learn about physical ocean properties, with a particular focus on carbon cycling. Other scientists aboard the ship measured aerosols and solar radiation, and recovered and deployed moorings that collect data during the remainder of the year.
The ship’s crew also made one unexpected recovery during the voyage.
A satellite had reported to its base station that a 400-meter-long biophysical mooring deployed about 10 years ago for a project led by Woods Hole Oceanographic Institution was calling home.
The mooring had been set in 450 meters of water but was lost in 2001 when it failed to rise to the surface when triggered to do so. Apparently, it was finally ready to be found. The location was only about eight hours away from the Palmer’s location when the call went out.
The ship crew and scientists recovered the entire string of instruments, covered with 10 years of marine growth, looking like some sea monster from a horror movie. “What a wild coincidence,” said Swift, who also reported a successful expedition. [For more information about the Swift cruise, see PolarTREC teacher Juan Botella's project page .]
Posted March 11, 2011
The research vessel Nathaniel B. Palmer continued its support of an expedition to the Ross Sea during the first half of the month.
Led by chief scientist Josh Kohut from Rutgers University , the primary research focused on the Ross Sea. The scientists are interested in learning about the phytoplankton at the base of the Ross Sea’s food web and the special combination of currents, nutrients, and trace metals that allow it to thrive. (For more information, see the project Web site, Ross Sea Connection .)
Other projects aboard the ship studied more deeply the relationships between certain types of plankton; the recovery of two moorings that were deployed in 2008; and the recovery of a couple of autonomous gliders that were released off the sea ice edge earlier in the field season.
A deep underwater glider released off the sea ice edge from McMurdo Station in December had spent 55 days in the Ross Sea before the Palmer left the ice pier on the month-long cruise. It continued to probe the underwater oceanography of the region during the research cruise, with two other shallow gliders from the ship, for five glider missions.
A storm on Feb. 13 forced the Palmer to abandon its last day of work before heading back to McMurdo, though the expedition was highly successful otherwise.
The ship then departed McMurdo Station about a week later on its third mission since leaving Punta Arenas in November. It will reverse course back to Chile for a 70-day cruise with another shipful of scientists, led by Jim Swift of Scripps Institution of Oceanography .
Swift and colleagues will perform a variety of physical oceanographic measurements, looking at processes like ocean circulation and the carbon cycle. The Southern Ocean is a critical sink for carbon. Once locked into the deep ocean, carbon can remain out of the atmosphere for hundreds of years, helping to reduce the buildup of CO2 in the atmosphere that’s warming the planet.
Posted February 4, 2011
The research vessel Nathaniel B. Palmer pulled into McMurdo Station toward the end of January, ending a nearly two-month research cruise in tandem with the Swedish icebreaker Oden .
Scientists aboard the two ships conducted a wide variety of research, from studying a potential invasion of king crabs onto the continental shelf to the unusually high biological activity associated with an ice-free area called a polynya in the Amundsen Sea. [See previous article: Two ships, one mission.]
Photo Credit: Peter Rejcek
The PALMER and ODEN in McMurdo Sound in January 2011 after nearly two months at sea.
The latter study, called the Amundsen Sea Polynya International Research Expedition (ASPIRE) , spent several weeks measuring the extent and characteristics of the phytoplankton bloom and associated biology in the ice-free region of sea ice.
The scientists employed a variety of instruments, from nets used to capture tiny critters that feed on the free-floating plants, to an underwater glider that measures various physical properties of the ocean. [See previous article: Aspiring for knowledge.]
“Preliminary results reveal that the phytoplankton bloom in the Amundsen Sea polynya exceeds all expectations, being greater even than the reported ‘big bloom’ of February 2009,” wrote ASPIRE chief scientist Patricia Yager in the ship’s weekly science report, at the end of December.
The new year brought some challenges to the expedition. An effort to access Pine Island Bay, an area undergoing dynamic changes, proved impossible due to sea ice cover. Meanwhile, the Slocum glider developed a leak, forcing it to send a distress signal for recovery — a task that proved particularly difficult in rough seas.
However, the autonomous gilder, which moves through the water in a seesaw pattern by changing buoyancy, was eventually recovered, repaired and redeployed.
Toward the end of the cruise, as the ship waited to dock at McMurdo’s ice pier, Yager wrote: “We are truly impressed by this very fine research vessel, its outstanding captain and crew, and the highly talented [Raytheon Polar Services ] support that enabled us to achieve and often exceed our science goals. The Amundsen Sea has fewer secrets this week.”
After only a brief two days, the Palmer left McMurdo for a month-long expedition to the Ross Sea with four new science teams aboard.
Let by chief scientist Josh Kohut from Rutgers University , the primary research will focus on the Ross Sea. The scientists are interested in learning about the phytoplankton at the base of the Ross Sea’s food web and the special combination of currents, nutrients, and trace metals that allow it to thrive. (For more information, see the project Web site, Ross Sea Connection .)
Other projects aboard the ship will look more deeply at the relationships between certain types of plankton; the recovery of two moorings that were deployed in 2008; and the recovery of a couple of autonomous gliders that were released off the sea ice edge earlier in the field season.
Posted January 7, 2011
The research vessel Nathaniel B. Palmer rendezvoused with the Swedish icebreaker Oden in the Amundsen Sea shortly before Christmas as part of an international two-ship expedition that left Punta Arenas, Chile, in late November.
Scientists aboard the two ships are conducting a wide variety of research, from studying a potential invasion of king crabs onto the continental shelf to the unusually high biological activity associated with an ice-free area called a polynya in the Amundsen Sea. [See previous article: Two ships, one mission.]
The rendezvous was mostly to swap personnel. The “crab team” aboard the Palmer switched over to the Oden after working aboard the U.S. Antarctic Program vessel for several weeks.
According to the logs of the Palmer’s chief scientist, Patricia Yager with the University of Georgia , the crab team has collected about 100,000 images of the continental slope of Antarctica across some 30 nautical miles using a camera aboard an autonomous underwater vehicle.
Photo Credit: Patricia Yager
Scientists aboard the ODEN inspect a conductivity, temperature and depth (CTD) instrument that also collects water samples.
Sven Thatje , principal investigator on the crab project, reported finding the invasive predators along the continental slope.
“Range extensions of predatory crabs into shallower water are likely as waters along the [Western Antarctica Peninsula] continue to warm. This implies that benthos of shallower waters will be exposed to predatory pressures not experienced for tens of millions of years.” [See previoius article: Crushing blow.]
More recently, work aboard the ship has shifted in support the project by Yager and colleagues, called the Amundsen Sea Polynya International Research Expedition (ASPIRE) . [See previous article: Aspiring for knowledge.] A polynya is a seasonally recurring pool in the sea ice caused by either winds (latent heat polynya) or ocean heat from below (sensible heat polynya). This particular one is the most biologically active in Antarctica, producing intense phytoplankton blooms.
It took the Palmer about two days to break into the polynya in mid-December from the outer marginal ice zone. Once inside the polynya, the crew released an underwater glider that will seesaw through the water for about two weeks collecting information about the physical and biological properties of the ocean. The team also deployed a moored sediment trap that will help the scientists understand the dynamics of the carbon cycle in the polynya.
The nearly two-month expedition will end in mid-January at McMurdo Station .
Posted November 5, 2010
The research vessel Nathaniel B. Palmer left Punta Arenas, Chile, on Oct. 23 for a three-week science cruise that will keep the ship mostly in the Drake Passage, the infamously rough stretch of water between the tip of South America and the Antarctic Peninsula.
Photo Credit: Scott Walker/Antarctic Photo Library
The GOULD and PALMER at port in Puerto Natales, Chile.
A team of oceanographers aboard the ship, led by Teresa Chereskin with the Scripps Institution of Oceanography at the University of California in San Diego , is studying the world’s largest ocean current, the Antarctic Circumpolar Current. Drake Passage, the chokepoint where the current narrows, is an ideal place to study the ACC, according to Chereskin.
Several years ago, Chereskin and her team deployed more than three dozen instruments called current and pressure measuring inverted echo sounders (CPIES) in a line across the passage, as well as in a more densely packed array to map circulation and eddy patterns of the ACC.
The devices use sound to determine water temperature. Sound travels faster in warmer water than colder water, so by sending a short sound through the water and listening for how long it travels, the researchers can infer the average temperature of the water.
Sunny weather greeted the Palmer on its first cruise since the end of June, though strong winds prevailed for much of the first week of operations. At last report, the ship and its crew had been successful in retrieving data from several sites.
Posted July 9, 2010
The research vessel Nathaniel B. Palmer spent early June wrapping up a whale research mission off the Antarctic Peninsula.
The six-week cruise was in support of chief scientist Douglas Nowacek , with Duke University , who is studying the feeding behavior of the large marine mammals, particularly humpback whales.
The researchers use small inflatable boats to tag the whales with instruments that attach to their broad bodies with a suction cup. The temporary tags help measure whale diving and feeding behavior. The scientists also monitor the size and density of schools of krill, a shrimplike animal the whales prey upon.
The month got off to a good start with the first clear day in weeks. The day’s highlight was a pod of 15 or so Arnoux’s beaked whales, a slender whale with a pronounced snout.
Photo Credit: Brian Nelson/Antarctic Photo Library
A humpback whale tail spotted off the Antarctic Peninsula.
“We’ve been waiting for this opportunity all cruise,” wrote marine project coordinator Jamee Johnson in the ship’s daily log. “We deployed a boat, but were unable to catch up with the elusive creatures.”
A couple of days of poor weather around Palmer Station gave way to “spectacular” weather by June 4 in some nearby bays. The next day was even better, with a “stunning display” by a pod of orcas, which included the most enormous male anyone had seen, Johnson wrote.
“The dorsal fin on the adult male was as tall as a person standing in a Zodiac beside it. The whales corralled a seal into the side of an iceberg, and when it tried to jump onto the berg, the giant male jumped out of the water and caught it just meters from the Zodiac.”
The Palmer then made a few additional surveys before heading north to Punta Arenas, Chile. The ship will be on standby until October.
For more information about the whale project, visit the project blog .
Posted June 11, 2010
The RVIB Nathaniel B. Palmer spent the month of May chasing and tagging whales for a project led by scientists from Duke University.
The six-week cruise is in support of chief scientist Douglas Nowacek , with Duke University , who is studying the feeding behavior of humpback whales. The researchers use small inflatable boats to tag the whales with instruments that attach to their broad bodies with a suction cup. The temporary tags help measure whale diving and feeding behavior. The scientists also monitor the size and density of schools of krill, a shrimplike animal the whales prey upon.
The scientists want to understand how much krill the whales eat in a given day, the threshold of prey necessary for them to be able to forage, and how they make decisions about feeding.
Quantifying the consumption rates is important for understanding the bigger ecological picture of the Antarctic Peninsula, parts of which are becoming more subantarctic as climate changes. Scientists have noted a decline in krill biomass, which they say is linked to the declining duration of winter sea ice, a key habitat for juvenile krill.
Mounting pressures on the krill population, including some commercial fisheries, make it necessary to understand the humpback whale’s role in the food web, Nowacek told the Sun in a previous article. [See related article: Tagged.]
“This is the second year of this project, and everyone aboard is ecstatic to be returning and to have the opportunity to continue the science,” said Jamee Johnson, marine projects coordinator, on the ship’s daily log.
The ship’s first stop in Wilhelmina Bay met with early success despite bad weather that hampered calibration of some instruments. “Preliminarily, it looks like this bay is as tightly packed with whales and prey as it was last year, which is excellent news for us,” Johnson wrote.
That first week out the science team managed to tag two humpback whales (Megaptera novaeangliae) and recorded 74 sightings of humpback whales in groups of two, representing about 150 whales.
The Palmer then moved to Andvord Bay, which was home to plenty of krill and minke whales, another species of interest to the science party. A few days later, in Flanders Bay, the ship crew spotted killer whales and conducted some work with the pod of about 15 animals, which included young calves.
A return to Wilhelmina Bay met with more success, as Johnson reported on May 19: “We woke up to Wilhelmina Bay teeming with life. We saw a glut of whales, including our first right whale sighting, plus enormous rafts of seals and penguins.” Several more whales were eventually tagged in the region, despite some “feisty” behavior.
For more information about the project, visit the project blog .
Posted May 7, 2010
The RVIB Nathaniel B. Palmer concluded its nearly two-month science cruise in support of a project to find the Antarctic silverfish.
Photo Credit: Peter Rejcek/Antarctic Photo Library
The RVIB Nathaniel B. Palmer near Palmer Station in January 2010.
Led by Joseph Torres, a University of South Florida marine biologist, the ship ranged across the Antarctic Peninsula for the silverfish, which has disappeared from much of its traditional territory. The 15-centimeter-long fish is an important part of the diet of bigger marine critters, such as Adélie penguins. The scientists believe the absence of the silverfish may be linked to the disappearance of sea ice from much of the northern west coast of the Antarctic Peninsula due to climate change.
Work aboard the ship included fish trawls along the coast, visits to penguin rookeries to sample their diets and lab work aboard the Palmer. [Torres contributed to a blog for the St. Petersburg Times.]
Also aboard the ship was a team from Wood Hole Oceanographic Institution led by Ken Buesseler . His group is studying the carbon cycle in the region, particularly the flux, or movement, of carbon particles through the water column into the deep ocean.
A third group from Oklahoma State University , led by Alexander Simms , is researching the sea-level history of the Antarctic Peninsula at the beginning of the Holocene as ice melted from the Last Glacial Maximum. Simms and company worked out of a field camp for a little less than a week, along a raised beach on the peninsula around Calmette Bay, to collect beach cobbles for later dating analysis.
While in the Marguerite Bay region, the ship made a brief port call at the British Rothera Base to pick up refrigerated vans housing ice cores collected from the Bruce Plateau on the peninsula as part of the Larsen Ice Shelf System, Antarctica (LARISSA) program . [See previous article: LARISSA.]
Other stops during the cruise include areas around Charcot Island, Avian Island and Renaud Island, as well as the Palmer Station area. The scientists captured more than 100 silverfish at each of the first two locations, according to a report from Torres.
The Palmer was scheduled to return to Punta Arenas at the end of April before turning around for a six-week cruise in support of Douglas Nowacek , a scientist from Duke University , who is studying the feeding behavior of humpback whales. [See previous article: Tagged.]