(Press-News.org) Many human communities want answers about the current status and future of Arctic marine mammals, including scientists who dedicate their lives to study them and indigenous people whose traditional ways of subsistence are intertwined with the fate of species such as ice seals, narwhals, walruses and polar bears.
But there are many unknowns about the current status of 11 species of marine mammals who depend on Arctic sea ice to live, feed and breed, and about how their fragile habitat will evolve in a warming world.
A recently published multinational study attempted to gauge the population trends of Arctic marine mammals and changes in their habitat, identify missing scientific information, and provide recommendations for the conservation of Arctic marine mammals over the next decades.
The Arctic sea ice cover, made of frozen seawater floating on top of the Arctic Ocean and its neighboring seas, naturally grows in the fall and winter and melts during the spring and summer every year. But over the past decades, the melt season has grown longer and the average extent of Arctic sea ice has diminished, changing the game for many Arctic marine mammals - namely beluga, narwhal and bowhead whales; ringed, bearded, spotted, ribbon, harp and hooded seals; walruses; and polar bears.
"This research would not have been possible without support from NASA," said Kristin Laidre, lead author of the new study and a polar scientist with University of Washington in Seattle. "NASA backed us on research related to the biodiversity and ecology of Arctic marine mammals, as well as the development of metrics for the loss of sea ice, their habitat."
Laidre's team used the Arctic sea ice record derived from microwave measurements taken by NASA and Department of Defense satellites. This record began in late 1978, is uninterrupted, and relies on NASA-developed methods for processing the microwave data.
"It's really our best global view of the Arctic sea ice," said Harry Stern, author of the paper with Laidre and a mathematician specializing in sea ice and climate at University of Washington.
Stern divided the Arctic Ocean into 12 regions. Using daily sea ice concentration data from the satellite record, he calculated changes in the dates of the beginning of the melt season in spring and the start of the fall freeze-up from 1979 to 2013. He found that, in all regions but one, the melt season had grown longer (mostly by 5 to 10 weeks, and by 20 weeks in one region).
"Sea ice is critical for Arctic marine mammals because events such as feeding, giving birth, molting, and resting are closely timed with the availability of their ice platform," Laidre said. "It is especially critical for the ice-dependent species -- seals and polar bears. Ice seals use the sea ice platform to give birth and nurse pups during very specific weeks of the spring, and polar bears use sea ice for feeding, starting in late winter and continuing until the ice breaks up."
Pacific walrus use the floating pack ice both as a platform on which to rest between feeding bouts and as a passive transport around their habitat.
"Loss of sea ice has resulted in walrus hauling out on land in Alaska and Russia in massive numbers - these land haul outs result in trampling of their young," Laidre said. "Also, now walrus must travel a longer way to reach their feeding areas, which is energetically costly."
In the case of Arctic whales, the changes in sea ice might benefit their populations, at least in the short term: the loss and earlier retreat of sea ice opens up new habitats and, in some areas of the Arctic, has also led to an increase in food production and the length of their feeding season.
In the future, Stern said higher-resolution satellite microwave data might come in handy when studying the interactions of Arctic marine mammals with their icy habitat.
"For example, we know that narwhals congregate in specific areas of the Arctic in the wintertime, so maybe a higher spatial resolution in these areas might help us better understand their relationship with the ice," Stern said. "But mainly, just continuing daily coverage is what's important for the long-term monitoring of habitat changes."
INFORMATION:
This review study was funded by the Greenland Institute of Natural Resources, the Danish Ministry of the Environment and NASA.
AUSTIN, Minn. (4/30/15) - Taking aspirin reduces a person's risk of colorectal cancer, but the molecular mechanisms involved have remained unknown until a recent discovery by The Hormel Institute, University of Minnesota.
Researchers led by The Hormel Institute's Executive Director Dr. Zigang Dong and Associate Director Dr. Ann M. Bode, who co-lead the Cellular & Molecular Biology section, discovered that aspirin might exert its chemopreventive activity against colorectal cancer, at least partially, by normalizing the expression of epidermal growth factor receptor (EGFR) ...
New York, NY (April 30, 2015) - The use of integrative medicine interventions leads to significant improvements in patient activation and patient-reported outcomes in the treatment of chronic pain, depression, and stress, according to a new report released by The Bravewell Collaborative. The findings are based on data collected by the Patients Receiving Integrative Medicine Interventions Effectiveness Registry (PRIMIER), the first-ever patient registry on integrative medicine.
"We are encouraged by these early results, and we see tremendous potential for PRIMIER to provide ...
Philadelphia, April 30, 2015 -- The American College of Physicians (ACP) today released clinical advice aimed at reducing overuse of cervical cancer screening in average risk women without symptoms. "Cervical Cancer Screening in Average Risk Women" is published in Annals of Internal Medicine and lists two concurring organizations: the American Congress of Obstetricians and Gynecologists and the American Society for Clinical Pathology.
"ACP's advice for cervical cancer screening is designed to maximize the benefits and minimize the harms of testing," said Dr. David Fleming, ...
1. American College of Physicians releases Best Practice Advice for the proper time, test, and interval for cervical cancer screening
ACP's advice is supported by ACOG and endorsed by ASCP
New clinical advice from the American College of Physicians (ACP) aims to reduce overuse of cervical cancer screening in average risk women without symptoms. "Cervical Cancer Screening in Average Risk Women" is published in Annals of Internal Medicine and lists two concurring organizations: the American Congress of Obstetricians and Gynecologists and the American Society for Clinical ...
HOUSTON - (April 30, 2015) - The percentage of Texans without health insurance dropped 31 percent since enrollment began in the Affordable Care Act's (ACA) Health Insurance Marketplace, according to a new report released today by the Episcopal Health Foundation and Rice University's Baker Institute for Public Policy.
The report found that from September 2013 to March 2015, the percentage of uninsured adult Texans ages 18-64 dropped from 25 to 17 percent.
"This is a dramatic drop that's unprecedented in Texas," said Elena Marks, president and CEO of the Episcopal Health ...
Due to a lack of suitable studies, no conclusions can be drawn on the patient-relevant benefit or harm of screening for asymptomatic bacteriuria (ASB) in pregnant women. The benefit of antibiotic treatment of ASB following screening is also an open issue, as the results of the over 40-year-old studies cannot be applied to the current healthcare situation. This is the result of the final report published by the German Institute for Quality and Efficiency in Health Care (IQWiG) on 23 April 2015, which was commissioned by the Federal Joint Committee (G-BA).
Maternity guidelines ...
A team of scientists has shed light on the dynamics of the creation, collaboration and dissemination processes involved in classical music works and styles. Their study focuses on analysing networks of composers contemporary to CD publications, using modern data analysis and data modelling techniques. These findings have just been published in EPJ Data Science by Doheum Park from the Graduate School of Culture Technology at Korea Advanced Institute of Science and Technology in Daejeon and colleagues. This work explores the nature of culture in novel ways, as part of a broader ...
This news release is available in French. Quebec City, April 30, 2015--Noroviruses, a group of viruses responsible for over 50% of global gastroenteritis cases, can spread by air up to several meters from an infected person according to a new study by Université Laval researchers. The discovery, details of which are presented in the latest issue of Clinical Infectious Diseases, suggests that measures applied in hospitals during gastroenteritis outbreaks may be insufficient to effectively contain this kind of infection.
The team led by Caroline Duchaine, professor ...
TAMPA, Fla. - DNA can be damaged by different environmental insults, such as ultraviolet light, ionizing radiation, oxidative stress or certain drugs. If the DNA is not repaired, cells may begin growing uncontrollably, leading to the development of cancer. Therefore, cells must maintain an intricate regulatory network to ensure that their DNA remains intact. Moffitt Cancer Center researchers have discovered a novel mechanism that controls a cell's response to DNA damage.
The protein SIRT1 plays an important role in controlling DNA damage. It can sense the presence of ...
Few doctors are prescribing a low-cost drug that has been proven effective in preventing the onset of diabetes, according to a UCLA study. The study, published in the peer-reviewed journal Annals of Internal Medicine, found that only 3.7 percent of U.S. adults with pre-diabetes were prescribed metformin during a recent three-year period.
Metformin and lifestyle changes both can prevent the onset of diabetes, but people often struggle to adopt healthier habits, according to Dr. Tannaz Moin, the study's lead author and an assistant professor of medicine in the division ...
