Constantine Alexander's Journal

Bison ready for new pastures?

Quarantine protocol successfully used to demonstrate brucellosis-free bison from infected herds

A bison in Yellowstone National Park. Photo by Julie Larsen Maher

A new study from the USDA Animal and Plant Health Inspection Services (APHIS) and the Wildlife Conservation Society (WCS) demonstrates that it is possible to qualify bison coming from an infected herd as free of brucellosis using quarantine procedures. These bison can then be used to seed conservation herds in other landscapes without the threat of spreading the disease.

In response to Interagency Bison Management Plan (IBMP) guidelines on federal and state bison management actions, the USDA, APHIS Brucellosis Eradication: Uniform Methods and Rules protocol for the quarantine of bison was tested to see if it could successfully be used to qualify the animals as brucellosis-free.

Results of the study indicated that it is feasible to take young bison from an infected population and, using the approved quarantine protocol published as a Federal Uniform Method and Rule (UM &R), qualify them as brucellosis-free in less than three years.

Between 2005 and 2008, more than 200 bison calves of Yellowstone National Park origin were transported to a quarantine facility at Corwin Springs Montana, just outside Yellowstone National Park. During the study, blood samples were collected from the animals every 30-45 days and tested for brucellosis. Those animals that tested positive were euthanized and those remaining were tested until all had two consecutive negative tests. Since the primary mode of brucellosis transmission is via abortion and birthing events, all animals testing negative were held until they produced their first calf and showed no evidence of the disease in newborn calves, birth fluids, or blood.

At that point, the bison were considered brucellosis-free. The study showed that all bison continued to be brucellosis-free over the course of the seven-year study after the initial screening period and through several calving cycles. No evidence of brucellosis was found in either newborn calves or their mothers.

"The results of this study indicate that under the right conditions, there is an opportunity to produce live brucellosis-free bison from even a herd with a large number of infected animals like the one in Yellowstone National Park," said Dr. Jack Rhyan, APHIS Veterinary Officer. "Additionally, this study was a great example of the benefits to be gained from several agencies pooling resources and expertise to research the critical issue of brucellosis in wildlife."

The authors of the study note that agencies charged with the management of bison agree that capture and relocation of bison to other suitable habitats would be an appropriate alternative to the lethal removal of bison that exceed population objectives for Yellowstone National Park, as defined by the IMBP. The UM &R protocol could facilitate such relocation by demonstrating animals are disease-free and would not transmit brucellosis to cattle or other animals.

At the same time, a movement to ecologically restore bison to large landscapes is gaining momentum throughout the United States and Canada, and brucellosis-free bison may be needed to seed those landscapes. In particular, the genetics of Yellowstone bison are important because they are known to be free of cattle genes and represent bison that existed on the Great Plains for thousands of years.

WCS Bison Project Coordinator Keith Aune said, "This study represents an important milestone in bison conservation and these research findings enable us to practice genetic rescue from brucellosis infected bison herds. The Yellowstone animals passing through this system of testing are critical to conserving the diversity of the bison genome over the long term. We've also learned a great deal about brucellosis blood testing and how to better interpret results when screening animals for this disease. It is our hope that several satellite herds of Yellowstone bison can be assembled from the animals that graduate through this quarantine process."

Citation: P. Ryan Clarke, DVM, MPH; Rebecca K. Frey, MS; Jack C. Rhyan, DVM, MS; Matt P. McCollum, MS; Pauline Nol, DVM, PhD; Keith Aune, MS; Feasibility of quarantine procedures for bison (Bison bison) calves from Yellowstone National Park for conservation of brucellosis-free bison; Journal of the American Veterinary Medical Association, DOI: 10.2460/javma.244.5.588. 

Funding for this study was provided by USDA APHIS, Montana Fish Wildlife and Parks and Montana Department of Livestock.

Contact: Scott Smith
718-220-3698
Wildlife Conservation Society

 

Study projects big thaw for Antarctic sea ice

Ross Sea will reverse current trend, become largely ice free by 2100

Changes in the extent and duration of Ross Sea ice will significantly impact marine life in what is one of the world’s most productive and unspoiled marine ecosystems, where rich blooms of phytoplankton feed krill, fish, and higher predators such as penguins. Photo courtesy of Walker Smith.

By David Malmquist

Antarctica's Ross Sea is one of the few polar regions where summer sea-ice coverage has increased during the last few decades, bucking a global trend of drastic declines in summer sea ice across the Arctic Ocean and in two adjacent embayments of the Southern Ocean around Antarctica.

Now, a modeling study led by Professor Walker Smith of the Virginia Institute of Marine Science suggests that the Ross Sea's recent observed increase in summer sea-ice cover is likely short-lived, with the area projected to lose more than half its summer sea ice by 2050 and more than three quarters by 2100.

These changes, says Smith, will significantly impact marine life in what is one of the world's most productive and unspoiled marine ecosystems, where rich blooms of phytoplankton feed krill, fish, and higher predators such as whales, penguins, and seals.

Smith, who has been conducting ship-based fieldwork in the Ross Sea since the 1980s, collaborated on the study with colleagues at Old Dominion University. Their paper, "The effects of changing winds and temperatures on the oceanography of the Ross Sea in the 21st century," appears in the Feb. 26 issue ofGeophysical Research Letters. Smith's co-authors are Mike Dinniman, Eileen Hofmann, and John Klinck.

Smith says "The Ross Sea is critically important in regulating the production of Antarctica's sea ice overall and is biologically very productive, which makes changes in its physical environment of global concern. Our study predicts that it will soon reverse its present trend and experience major drops in ice cover in summer, which, along with decreased mixing of the vertical column, will extend the season of phytoplankton growth. These changes will substantially alter the area's pristine food web."

Researchers attribute the observed increase in summertime sea ice in the Ross Sea—where the number of days with ice cover has grown by more two months over the past three decades—to a complex interplay of factors, including changes in wind speed, precipitation, salinity, ocean currents, and air and water temperature.

But global climate models agree that air temperatures in Antarctica will increase substantially in the coming decades, with corresponding changes in the speed and direction of winds and ocean currents. When Smith and his colleagues fed these global projections into a high-resolution computer model of air-sea-ice dynamics in the Ross Sea, they saw a drastic reduction in the extent and duration of summer sea ice.

The modeled summer sea ice concentrations decreased by 56% by 2050 and 78% by 2100. The ice-free season also grew much longer, with the mean day of retreat in 2100 occurring 11 days earlier and the advance occurring 16 days later than now.

Also changed was the duration and depth of the "shallow mixed layer," the zone where most phytoplankton live. "Our model projects that the shallow mixed layer will persist for about a week longer in 2050, and almost three weeks longer in 2100 than now," says Smith. "The depth of the shallow mixed layer will also decrease significantly, with its bottom 12% shallower in 2050, and 44% shallower in 2100 than now."

For Smith, these changes in ice, atmosphere, and ocean dynamics portend major changes in the Antarctic food web. On the bright side, the decrease in ice cover will bring more light to surface waters, while a more persistent and shallower mixed layer will concentrate phytoplankton and nutrients in this sunlit zone. These changes will combine to encourage phytoplankton growth, particularly for single-celled organisms called diatoms, with ripples of added energy potentially moving up the food web.

But, Smith warns, the drop in ice cover will negatively affect several other important species that are ice-dependent, including crystal krill and Antarctic silverfish. A decrease in krill would be particularly troublesome, as these are the major food source for the Ross Sea's top predators—minke whales, Adélie and Emperor penguins, and crabeater seals.

Overall, says Smith, "our results suggest that phytoplankton production will increase and become more diatomaceous. Other components of the Ross Sea food web will likely be severely disrupted, creating significant but unpredictable impacts on the ocean's most pristine ecosystem."

Citation: Walker O. Smith Jr., Michael S. Dinniman, Eileen E. Hofmann, John M. Klinck; The Effects of changing winds and temperatures on the oceanography of the Ross Sea in the 21st century; Geophysical Research Letters, DOI: 10.1002/2014GL059311. 

Contact: David Malmquist
804-684-7011
Virginia Institute of Marine Science

Plastic litter can pass on pollutants and chemical additives to marine wildlife

Photo credit: Chris Jordan (CC)

By Science for Environment Policy

New research has provided the first conclusive evidence that microplastics ingested by marine wildlife can transfer toxic pollutants to their tissues. The researchers studied lugworms fed on PVC particles contaminated with either widespread marine pollutants or plastic additives and found that these 'earthworms of the sea' absorbed the chemicals into their gut tissue, which reduced their ability to perform essential functions.

Plastic waste has been recognised as an area of high policy concern as evidenced by the recent Green Paper on a European Strategy on Plastic Waste in the Environment and concerns are now being raised regarding the transfer of potentially harmful chemicals from plastics to marine wildlife.

Microplastics, micrometre-sized particles formed by disintegration, can contain two types of chemical: additives from manufacture and pollutants from urban runoff that have attached themselves to the surface of the plastic. Previous research has shown correlations between levels of ingested plastics and concentrations of potentially harmful chemicals in animals, but this study is the first to demonstrate the actual transfer of chemicals from microplastics into gut tissue.

This study investigated the impact on lugworms (Arenicola marina), which maintain coastal biodiversity through digesting sediment and are eaten by wading birds, forming an important part of the food chain. The study focused on PVC (polyvinyl chloride) plastic, which is used in construction, clothing and upholstery and is commonly found in estuary sediment.

The researchers exposed particles of PVC to two widespread marine pollutants: nonylphenol (present in detergents) and phenanthrene (present in urban runoff from cars), at levels similar to those found in the environment. To investigate the impact of additives commonly used in plastic manufacture, a sample of PVC particles were exposed to PBDE-47 (a flame retardant) and triclosan (an anti-microbial agent).

Mixtures of microplastics and sand sediments (at a ratio of 5% microplastic to 95% sand) were then fed to lugworms over a period of ten days. Concentrations of all four chemicals in the gut indicated that both the pollutants and the additives had been transferred into the tissues. Concentrations were between 326% and 3770% greater in the gut tissues than in the contaminated mixtures. The additive PBDE-47 showed the greatest increase in concentration from particles to gut tissue at 3770%.

The researchers also investigated the effects of ingesting the contaminated microplastics on mortality, feeding and immunity of these animals. Results showed that the uptake of nonylphenol reduced the worms' ability to remove disease-causing bacteria by more than 60%. The uptake of the additive triclosan reduced the ability of lugworms to digest sediments by more than 50% and also increased mortality rates.

This study has provided evidence that ingestion of microplastics transfers pollutants and additives to tissues at concentrations sufficient to disrupt the health of lugworms. This is likely to have implications for biodiversity and ecosystem health as lugworms play an important role in maintaining the structure and functioning of diverse soft-sediment habitats. If marine litter is not strongly reduced or even stopped, with an increase of 33 billion tonnes of plastic produced by 2050, the results raise serious concerns for the future.

Citation: Browne, M.A., Niven, S.J., Galloway, T.S. et al. (2013). Microplastic Moves Pollutants and Additives to Worms, Reducing Functions Linked to Health and Biodiversity. Current Biology. 23:2388-2392. DOI: 10.1016/j.cub.2013.10.012.

Contact: M. A. Browne

 

Plastic pollution measured in Mediterranean seabirds

Yelkouan shearwater. Credit: Sergey Yeliseev (CC)

By Science for Environment Policy

Endangered Mediterranean seabirds are suffering from ingestion of plastic litter, a recent study has shown. Overall, 66% of 171 seabirds studied were found to have plastic fragments in their stomachs and the critically endangered Balearic shearwater was among the worst affected.

Plastic pollution in marine ecosystems is recognised as a key problem in the Marine Strategy Framework Directive and can have many damaging effects. A wide array of species, such as turtles, sea mammals and birds, may ingest fragments either accidently or because it resembles their prey. These fragments may then damage or block the digestive system or release toxic chemicals, seriously affecting the health of these animals. The Mediterranean Sea is particularly at risk from plastics pollution with its large areas of industrialised coastline and enclosed nature.

This study is the first to investigate the amount of plastic ingested by Mediterranean seabirds. The researchers collected 171 birds accidently caught by longliners (fishing boats using lines of baited hooks) between May 2003 and June 2010 along the Catalan coast in the western Mediterranean Sea. Nine species were caught in all, and included shearwaters, gannets, gulls, kittiwakes and skuas. The birds were dissected and the stomach contents were removed, sieved and identified.

The results showed that 113 of the birds (66%) had at least one piece of plastic in their stomachs. The average size of plastic fragment was 3.5 mm with an average weight of 2.26 milligrams. Assorted 'post-consumer' fragments – hard pieces of plastic from litter such as bottles or boxes – were the most common, followed by pieces of plastic bags or wrappings.

The researchers also found that numbers of pellets, used industrially to transport plastic before being used to produce goods, were very low. This is in line with other studies suggesting the occurrence of this type of plastic pollution has been falling since the 1980s, possibly as a result of policy measures. Recreational activities now seem to be the main source of pollution in the Mediterranean.

Cory's shearwaters (Calonectris diomedea) were worst affected, with 94% of these birds containing plastic fragments. They also contained relatively high numbers of fragments, 15 on average. Other species badly affected were Balearic shearwaters (Puffinus mauretanicus) and Yelkouan shearwaters (Puffinus yelkouan); in both species 70% of birds contained plastic fragments. The researchers suggest these effects may be because shearwaters are less able to regurgitate plastics than, for example, gulls.

All three of the worst affected are of conservation concern: the Balearic shearwater is listed as critically endangered by the IUCN, the Yelkouan shearwater is considered vulnerable and the Cory's shearwater is listed as vulnerable within Spain.

Long-term monitoring is needed to assess the effects of plastic pollution on marine wildlife, the researchers conclude. They also recommend developing stricter controls on waste dumping, aided by bodies such as the Marine Strategy Framework Directive's technical subgroup on marine litter.

Citation: Codina-García, M., Militão, T., Moreno, J. González-Solís, J. (2013). Plastic debris in Mediterranean seabirds. Marine Pollution Bulletin. 77: 220–226. DOI: 10.1016/j.marpolbul.2013.10.002.

Contact: Marina Codinag and J. Gonzalez Solis

Waterbirds' hunt aided by specialized tail

Swimming birds evolved rudder-like tail to dive for food

Credit: Constantine Alexander (c)

The convergent evolution of tail shapes in diving birds may be driven by foraging style, according to a paper published in PLOS ONE on February 26, 2014 by Ryan Felice and Patrick O'Connor from Ohio University.

Birds use their wings and specialized tail to maneuver through the air while flying. It turns out that the purpose of a bird's tail may have also aided in their diversification by allowing them to use a greater variety of foraging strategies. To better understand the relationship between bird tail shape and foraging strategy, researchers examined the tail skeletal structure of over 50 species of waterbirds, like storks, pelicans, and penguins, and shorebirds, like gulls and puffins. They first categorized each species by foraging strategy, such as aerial, terrestrial, and pursuit diving, and then compared the shape and structure of different tails.

Scientists found that foraging style groups differed significantly in tail skeletal shape, and that shape could accurately "predict" foraging style with only a small amount of mismatch. In particular, underwater foraging birds, such as cormorants, penguins, puffins, gannets, and tropicbirds, have separately evolved a similarly specialized elongated tail structure, whereas aerial and terrestrial birds have a short, dorsally deflected tail structure. Moreover, each underwater foraging group, such as foot propelled, wing propelled, or plunge diving, had a distinctive tail-supporting vertebrae shape. According to the authors, the probable separate evolution of the specialized tail in underwater-diving birds may suggest that body structure adapted to the demand, or the need to move the tail as a rudder during underwater foraging. In contrast, the authors found no conclusive results when looking at the relationship between tail shape and flight style.

Mr. Felice adds, "Previous research has shown that diving birds evolve specializations in wing and leg morphology to facilitate underwater locomotion. This study puts a necessary focus on the tail, finding that this region of the body also evolves in response to the demands of underwater movement."

Citation: Felice RN, O'Connor PM (2014) Ecology and Caudal Skeletal Morphology in Birds: The Convergent Evolution of Pygostyle Shape in Underwater Foraging Taxa. PLoS ONE 9(2): e89737. doi:10.1371/journal.pone.0089737. 

Whales, ships more common through Bering Strait

Humpback whale breaching off the coast of Juneau, Alaska. They are now heard traveling north to feed in the Chukchi Sea. (Wikimedia / Gillfoto)

The Arctic is home to a growing number of whales and ships, and to populations of sub-Arctic whales that are expanding their territory into newly ice-free Arctic waters.

A study of the narrow passage of the Bering Strait uses underwater microphones to track the whales by their sounds. Three years of recordings reveal more detections of both Arctic and sub-Arctic whales traveling through the narrow choke point.

Kate Stafford, an oceanographer with the University of Washington's Applied Physics Laboratory, will present the results Feb. 26 at the Ocean Sciences meeting in Honolulu.

The recordings show Arctic beluga and bowhead whales migrating seasonally through the region from the Arctic south to spend winter in the Bering Sea. They also detect large numbers of sub-Arctic humpback, fin and killer whales traveling north through the Bering Strait to feed in the biologically rich Chukchi Sea.

"It's not particularly surprising to those of us who work up in the Arctic," Stafford said. "The Arctic seas are changing. We are seeing and hearing more species, farther north, more often. And that's a trend that is going to continue."

Stafford placed microphones below the water's surface and recorded in summer and early winter from 2009 to 2012 as part of a U.S.-Russian scientific collaboration. Melodious humpback whale songs showed up regularly on recordings into late fall. Fin and killer whales, which are southern species that seldom travel into Arctic waters, were heard into early November.

"These animals are expanding their range," Stafford said. "They're taking advantage of regions in seasons that they may not have previously."

The recordings also picked up ships using the ice-free summers to travel through two international shipping lanes. This poses an increased risk of collisions between whales and ships, and of noise pollution.

"Marine mammals rely primarily on sound to navigate, to find food and to find mates. Sound is their modality," Stafford said. "If we increase the ambient sound level, it has the potential to reduce the communication range of cetaceans and all marine mammals."

  The Bering Strait is a shallow, 58-mile-wide channel between Russia and Alaska that connects the Pacific and Arctic oceans. The Chukchi Sea is to the north, and the Bering Sea is to the south. Credit: NASA

The Bering Strait is famous as a land bridge that prehistoric humans used to travel from Russia to North America. Today, the waterway is 58 miles wide and maximum 160 feet deep, with about one-third of its span in U.S. waters and the rest in Russia. The two coasts are quite different, Stafford said, which makes the international collaboration essential to understanding the full environment.

A recent paper by Stafford and other scientists includes visual sightings of killer whales, a quieter southern-dwelling whale, just north of the strait in the southern Chukchi Sea. Killer whales are now seen fairly regularly in this area, which is being considered for oil and gas exploration.

"The Arctic areas are changing," Stafford said. "They are becoming more friendly to sub-Arctic species, and we don't know how that will impact Arctic whales. Will they be competitors for food? Will they be competitors for habitat? Will they be competitors for acoustic space, for instance these humpbacks yapping all the time in the same frequency band that bowheads use to communicate? We just don't know."

 

Stafford supports the idea of slowing ship speeds in the Bering Strait, reducing motor noise and the chance of ship strikes.

Another suggestion to protect whales builds on tagging work showing that bowhead whales tend to travel up the U.S. side on the way north in the spring and on the Russian side on their way back in the fall. The proposal suggests that ships follow the American coast in the fall and the Russian coast in the spring to reduce interactions between ships and whales.

Still to be explored is whether the increased whale travel through the region is due to rising whale populations, expanded ranges, or both. Logbooks from Soviet whaling ships in the mid-to-late 20th century report sub-Arctic whales in the region, but none were seen from about 1980 to 2010.

"The question is, are these whale populations recovering and so they're reoccupying former habitat, or are they actually invading the Arctic because they can, because there is less seasonal sea ice?" Stafford said.

Citation: Clarke, J., K. Stafford, S.E. Moore, B. Rone, L. Aerts, and J. Crance. 2013. Subarctic cetaceans in the southern Chukchi Sea: Evidence of recovery or response to a changing ecosystem. Oceanography26(4):136–149, http://dx.doi.org/10.5670/oceanog.2013.81.

Collaborators on the research are Janet Clarke at Leidos Inc. and Sue Moore at the National Oceanic and Atmospheric Administration. The research was funded by the U.S. National Science Foundation, the National Oceanic and Atmospheric Administration, and the Interior Department’s Bureau of Ocean and Energy Management.

Contact: Hannah Hickey
206-543-2580
University of Washington

Smithsonian scientists solve 'sudden death at sea' mystery

Clues unearthed in an ancient whale graveyard

Chilean and Smithsonian paleontologists study several fossil whale skeletons at Cerro Ballena, next to the Pan-American Highway in the Atacama Region of Chile, 2011. Photo by Adam Metallo

By John Barrat

Mass strandings of whales have puzzled people since Aristotle. Modern-day strandings can be investigated and their causes, often human-related, identified. Events that happened millions of years ago, however, are far harder to analyze—frequently leaving their cause a mystery. A team of Smithsonian and Chilean scientists examined a large fossil site of ancient marine mammal skeletons in the Atacama Desert of Northern Chile—the first definitive example of repeated mass strandings of marine mammals in the fossil record. The site reflected four distinct strandings over time, indicating a repeated and similar cause: toxic algae. The team's findings will be published Feb. 26 in the Proceedings of the Royal Society B.

The site was first discovered during an expansion project of the Pan-American Highway in 2010. The following year, paleontologists from the Smithsonian and Chile examined the fossils, dating 6-9 million years ago, and recorded what remained before the site was paved over.

The team documented the remains of 10 kinds of marine vertebrates from the site, named Cerro Ballena—Spanish for "whale hill." In addition to the skeletons of the more than 40 large baleen whales that dominated the site, the team documented the remains of a species of sperm whale and a walrus-like whale, both of which are now extinct. They also found skeletons of billfishes, seals and aquatic sloths.

What intrigued the team most, however, was how the skeletons were arranged. The skeletons were preserved in four separate levels, pointing to a repeated and similar underlying cause. The skeletons' orientation and condition indicated that the animals died at sea, prior to burial on a tidal flat.

 

Effects of Toxic Algae

Today, toxins from harmful algal blooms, such as red tides, are one of the prevalent causes for repeated mass strandings that include a wide variety of large marine animals.

"There are a few compelling modern examples that provide excellent analogs for the patterns we observed at Cerro Ballena—in particular, one case from the late 1980s when more than a dozen humpback whales washed ashore near Cape Cod, with no signs of trauma, but sickened by mackerel loaded with toxins from red tides," said Nicholas Pyenson, paleontologist at the Smithsonian's National Museum of Natural History and lead author of the research. "Harmful algal blooms in the modern world can strike a variety of marine mammals and large predatory fish. The key for us was its repetitive nature at Cerro Ballena: no other plausible explanation in the modern world would be recurring, except for toxic algae, which can recur if the conditions are right."

Harmful algal blooms are common along the coasts of continents; they are enhanced by vital nutrients, such as iron, released during erosion and carried by rivers flowing into the ocean. Because the Andes of South America are iron-rich, the runoff that has occurred along the west coast of South America for more than 20 million years has long provided the ideal conditions for harmful algal blooms to form.

From their research, the scientists conclude that toxins generated by harmful algal blooms most likely poisoned many ocean-going vertebrates near Cerro Ballena in the late Miocene (5-11 million years ago) through ingestion of contaminated prey or inhalation, causing relatively rapid death at sea. Their carcasses then floated toward the coast, where they were washed into a tidal flat by waves. Once stranded on the tidal flat, the dead or dying animals were protected from marine scavengers, and there were no large-land scavengers in South America at this time. Eventually, the carcasses were buried by sand. Because there are four layers at Cerro Ballena, this pathway from sea to land occurred four different times during a period of 10,000 to 16,000 years in the same area.

"Cerro Ballena is the densest site for individual fossil whales and other extinct marine mammals in entire world, putting it on par with the La Brea Tar Pits or Dinosaur National Monument in the U.S.," Pyenson said. "The site preserves marine predators that are familiar to modern eyes, like large whales and seals. However, it also preserves extinct and bizarre marine mammals, including walrus-like whales and aquatic sloths. In this way, the site is an amazing and rare snapshot of ancient marine ecosystems along the coast of South America."

Chilean and Smithsonian paleontologists study several fossil whale skeletons at Cerro Ballena, next to the Pan-American Highway in the Atacama Region of Chile, 2011. Photo by Adam Metallo

3-D Technology at Cerro Ballena

Because the site was soon to be covered by the Pan-American Highway, time was very limited for the researchers. A major solution came in the form of 3-D technology. Pyenson brought a team of Smithsonian 3-D imaging experts to Chile, who spent a week scanning the entire dig site.

Although all the fossils found from 2010 to 2013 have been moved to museums in the Chilean cities of Caldera and Santiago, the Smithsonian has archived the digital data, including the 3-D scans, from the site at cerroballena.si.edu. There, anyone can download or interact with 3-D models of the fossil whale skeletons, scan Google Earth maps of the excavation quarries, look at a vast collection of high-resolution field photos and videos or take 360-degree tours of the site.

The enormous wealth of fossils that the team examined represents only a fraction of the potential at Cerro Ballena, which remains unexcavated. The scientists conservatively estimate that the entire area preserves several hundred fossil marine mammal skeletons, awaiting discovery. Pyenson's colleagues at the Universidad de Chile in Santiago are actively working to create a research station near the fossils of Cerro Ballena so that those that have been collected and those still covered by sediments can be protected for posterity.

Contact: John Gibbons
202-633-5187
Smithsonian

New digital atlas details Alaska sea ice history since 1860

New research data set for climate study

Want to know how much of the Beaufort Sea was covered in ice in January 1850? You can now do so, thanks to a new website developed with support from by the Alaska Ocean Observing System (AOOS), a region of the NOAA-led U.S. Integrated Ocean Observing System (IOOS).

The new portal is a result of a collaboration with the Alaska Center for Climate Assessment and Policy (ACCAP), the Scenarios Network for Alaska and Arctic Planning (SNAP) and AOOS . It is the first digital atlas of historical sea ice concentration for Alaska's Beaufort, Chukchi, and Bering seas, and allows users to view and download sea ice concentration data from 1850 to the present. This objective, historical record of sea ice conditions spans nearly two centuries and provides researchers with a reliable tool to evaluate climate change impacts.

The data powering the tool comes from more than ten different sources, including the satellite record (1979-present), various U.S. Naval and National Ice Center compilations (1950s to 1990s), Canadian records (1950s to 1980s), Danish and Norwegian ship records (mid-1800s to 1970s), and whaling ship reports (1850-1900).

Users can select particular dates and locations, and watch animations of how open water seasons have varied in time and space. Requests for data can also be processed in graphic or map formats. Additionally, the atlas includes a detailed glossary on types of sea ice and information on original data sources and how the data were compiled.

One of the objectives of the project is to offer researchers a reliable tool to find time scales of variability, such as whether there is a 20-year cycle in sea ice. "That is a research question. Researchers want to know about it scientifically," said project lead John Walsh, University of Alaska Fairbanks. "If you only have 30 years of data, it's really hard to say there is a 20-year cycle. But when you get to 160 years, you can start to see if any cycles hold up over time, whether they are reliable, robust enough to be considered real."

Walsh points out, however, that the data represents "snapshots" in time, as well as historical trends in arctic sea ice cover and extent. They are not projections or predictions of future conditions, nor is the atlas designed for forecasting or prediction, but it can provide useful historical context for future planning efforts.

"This is an excellent example of bringing together, in one location and in a common format, data that can inform not only researchers and coastal resource managers, but the general public as well," said Zdenka Willis, director of the NOAA-led U.S. IOOS Program.

Users of the site could range from coastal community residents, fishermen and hunters, the oil and gas energy industries, military and maritime shipping agencies and scientists. It can be a powerful educational classroom tool as well. AOOS will soon be integrating these data layers into their statewide portal so users can view them alongside real-time conditions, forecast models, and a variety of GIS data.

The sea ice atlas supports NOAA's efforts to develop a national IOOS for tracking, predicting, managing and adapting to changes in the marine environment. IOOS delivers data and information needed to increase understanding of the nation's waters to improve safety, enhance the economy, and protect our environment.

Contact: Ben Sherman
301-713-3066
NOAA

Vitamin water: Measuring essential nutrients in the ocean

The phrase, 'Eat your vitamins,' applies to marine animals just like humans. Many vitamins, including B-12, are elusive in the ocean environment.

University of Washington researchers used new tools to measure and track B-12 vitamins in the ocean. Once believed to be manufactured only by marine bacteria, the new results show that a whole different class of organism, archaea, can supply this essential vitamin. 

"The dominant paradigm has been bacteria are out there, making B-12, but it turns out that one of the most common marine bacteria doesn't make it," said Anitra Ingalls, a UW associate professor of oceanography.

All marine animals, some marine bacteria and some tiny marine algae, or phytoplankton, need B-12, but only some microbes can produce the large, complex molecule. So like human vegetarians on land, marine organisms may be scouring for food that can help stave off vitamin deficiency.

"If only certain bacteria can make B vitamins, that can make B-12 a controlling factor in the environment. Is it present or not?" said Katherine Heal, a UW oceanography graduate student. "Studying the marine microbiome can help us understand what microbial communities could be supported where, and how that affects things like the ocean's capacity to absorb atmospheric CO2."

The UW team is the first to show that marine archaea, a single-celled organism that evolved totally separate from bacteria and all other living things, are making B-12. Relatives of these tiny critters are known for unusual behavior like living inside hot springs and underwater volcanoes.

The Seattle team managed to grow a common type of open-ocean archaea in the lab, no mean feat, and show that it not only makes enough B-12 to support its own growth but can supply some to the environment.

"It's hard to quantify their contribution," Ingalls said. "This is a first glimpse at their potential to contribute to this pool of vitamins."

The analysis was done at a new UW marine chemistry center that does detailed analysis of proteins and other carbon-based chemicals in the ocean. The researchers used high-tech tools, including liquid chromatography and mass spectrometry, to identify the tiny amount of vitamins among all the dissolved matter and salt in the seawater. The UW method is unique in that it is the only one that can distinguish among the four forms of B-12 vitamins.

UW graduate student Katherine Heal (far right) attaches a water collection bottle to an oceanographic instrument that will be lowered in water off Washington’s coast.

Field experiments involved sampling seawater in Hood Canal, near Seattle, and in the Pacific Ocean hundreds of miles offshore. The results showed that B-12 was present in small amounts in all water samples. Concentrations were low enough in some places that vitamin deficiency among tiny marine algae, or phytoplankton, is likely.

"Having a very small amount doesn't mean there's a very small supply," Ingalls said. "Low concentrations can indicate something that's highly desirable to marine organisms."

The next step, researchers said, is to connect different microbes' activity with the production of B vitamins, to see which organisms are responsible where, and to look at how ocean vitamins affect the type and amount of phytoplankton growing in the water.

Recent sequencing of the genomes of marine microbes has revealed genetic pathways in bacteria and archaea for creating B vitamins, but just because the gene is there doesn't mean it's being used. Marine microbes often adapt their behavior depending on the environment. In the case of vitamins, some bacteria make more B-12 if a phytoplankton is nearby, supporting their eventual food source.

Making a B-12 vitamin, which has a metal core and complex surrounding structure, involves 30-some steps.

"People think that's why many organisms have lost it from their genomes," Heal said. "It's just too expensive to make it, and it's easier to get it from food."

The UW team hopes to learn which microbes are producing B-12 vitamins where, to better understand how the base of the marine food web works, how it might alter in a changing environment, how oceans might help regulate atmospheric carbon dioxide, and where marine animals could go to get a well-balanced diet.

"The public really has a very strange relationship to microorganisms," Ingalls said. "People know they cause disease, so they want to kill them. But they're also the only reason that we – or whales, fish or coral reefs – are alive."

Collaborators are David Stahl, E. Virginia Armbrust, Allan Devol, Wei Qin and Laura Carlson at the UW, James Moffett at the University of Southern California and Willow Coyote, an undergraduate from Evergreen State College. The work was funded by the National Science Foundation.

Contact: Hannah Hickey
206-543-2580
University of Washington

What is El Nino Taimasa?

Flat-top Porites coral on a shallow reef near American Samoa. Coral heads are fully submerged under normal conditions. During El Niño Taimasa, tops of large flat coral on the reef are exposed to air at low tide. Image courtesy of the National Park of American Samoa.

During very strong El Niño events, sea level drops abruptly in the tropical western Pacific and tides remain below normal for up to a year in the South Pacific, especially around Samoa. The Samoans call the wet stench of coral die-offs arising from the low sea levels "taimasa" (pronounced [kai' ma'sa]). Studying the climate effects of this particular variation of El Niño and how it may change in the future is a team of scientists at the International Pacific Research Center, University of Hawai'i at Mānoa and at the University of New South Wales, Australia.

Two El Niño Taimasa events have occurred in recent history: 1982/83 and 1997/98. El Niño Taimasa differs from other strong El Niño events, such as those in 1986/87 and 2009/10, according to Matthew Widlansky, postdoctoral fellow at the International Pacific Research Center, who spearheaded the study.

"We noticed from tide gauge measurements that toward the end of these very strong El Niño events, when sea levels around Guam quickly returned to normal, that tide gauges near Samoa actually continued to drop," recalls Widlansky.

During such strong El Niño, moreover, the summer rain band over Samoa, called the South Pacific Convergence Zone, collapses toward the equator. These shifts in rainfall cause droughts south of Samoa and sometimes trigger more tropical cyclones to the east near Tahiti.

Using statistical procedures to tease apart the causes of the sea-level seesaw between the North and South Pacific, the scientists found that it is associated with the well-known southward shift of weak trade winds during the termination of El Niño, which in turn is associated with the development of the summer rain band.

Looking into the future with the help of computer climate models, the scientists are now studying how El Niño Taimasa will change with further warming of the planet. Their analyses show, moreover, that sea-level drops could be predictable seasons ahead, which may help island communities prepare for the next El Niño Taimasa.

Citation: Widlansky, M.J., A. Timmermann, S. McGregor, M.F. Stuecker, and W. Cai, 2014: An interhemispheric tropical sea level seesaw due to El Niño Taimasa. J. Climate, 27 (3), 1070-1081, doi:10.1175/JCLI-D-13-00276.1.

Contact: Gisela Speidel
808-956-9252
University of Hawaii ‑ SOEST