Posts Tagged "Svalbard"

Ice loss surpasses poaching as largest threat to Barents Sea polar bear

Posted by on Aug 10, 2016 in All Posts, Featured Posts, Science | 0 comments

Ice loss surpasses poaching as largest threat to Barents Sea polar bear

Spread the News:SharePrior to the 1970s, hunting decimated polar bear populations across the Arctic. The international community has made strides in protecting the iconic species from over-harvesting through conservation agreements, which have helped the species start to recover. However, a review paper published in Polar Research in July suggests that the road to recovery is far from over, as ice loss now replaces poaching as the most pressing threat to polar bear survival in the Barents Sea area, north of Norway and Russia. The paper, written by Magnus Anderson and Jon Aars, of the Norwegian Polar Institute, comprehensively covers the history of polar bear population changes over the course of 100 years. By examining historical documents and current scientific studies, the authors find that ice loss, in conjunction with human encroachment on habitat and pollution, have replaced hunting as the largest threat to polar bear populations in the Barents Sea area. Somewhere between 100 and 900 polar bears were poached each year between 1870 to 1970 in Greenland and the Barents Sea region. Arctic countries then came together to protect the species as the bears were pushed toward the brink of extinction. In 1973, the Agreement on the Conservation of Polar Bears was facilitated by the International Union for Conservation of Nature and signed by five countries, marking an important step in the conservation of the polar bear and Arctic ecosystem. With the additional support of Russia’s and Norway’s polar bear hunting bans, enacted in 1956 and 1973, respectively, the Barents Sea polar bear’s outlook became more promising. In Svalbard, a glacier-rich archipelago north of the Norwegian mainland, polar bear populations doubled in the decade following the conservation agreement. There were approximately 2,000 bears in the region as of 1980. While population recovery occurred, it happened slower than anticipated by the scientific community. The Intergovernmental Panel on Climate Change mentioned the impacts of climate change on sea-ice cover for the first time in its third assessment in 2001. The inclusion of ice loss in the report shed light on a potential new threat to polar bear populations, which depend on the Arctic ice for their way of life. It also offered an explanation for the slow recovery of the species following the Russian and Norwegian poaching bans. According to current assessments, the polar bear habitat in the Barents Sea will substantially decrease over the next few decades due to ice loss and glacier retreat, as a consequence of anthropogenic climate change. Polar bear populations are expected to decline accordingly. The Polar Research study states that the main reason for the loss of polar bear populations will be the loss of an ice “platform” needed to hunt for prey — ringed, bearded, and harp seals. As the ice melts, polar bears lose their hunting grounds and must travel greater distances under more treacherous conditions in order to find food. Anderson and Aars cite prior studies conducted by Carla Freitas, Ian Stirling, and others which have tracked trends in polar bear movement with GPS collars and have found that the thickness and persistence of ice significantly affects the location of polar bears and their hunting grounds. In addition to impacting the species’ hunting ability, ice is critical for breeding, traveling, and denning. A loss of  habitat means fewer travel routes for males to find females during the breeding season and a drop in breeding rates across the Arctic. According to the authors’ research, when females have to give birth and raise their cubs, they are hard-pressed to find suitable denning and birthing areas. In the fall, the ice and snow begins...

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Polar Ecology in Flux Due to Climate Change

Posted by on Jul 20, 2016 in All Posts, Featured Posts, Science | 0 comments

Polar Ecology in Flux Due to Climate Change

Spread the News:ShareGlacial melting and rising ocean temperatures are affecting the feeding, breeding and dispersion patterns of species, such as krill, cod, seals and  polar bears, in the polar regions, according to two recently published research articles. This climatic shift could create an imbalance in the regional ecology and negatively impact numerous species as the effects of climate change worsen. The first article reflects on how a threat to a key species in Antarctica may shake up the food chain, while the other considers how a changing habitat in the Arctic could skew the population trends of several interconnected species and create a systemic imbalance in the ecosystem. After a nine-year study of krill in Potters Cove, a small section of King George Island off the coast of Antarctica, a team of South American and European marine biologists published their research this past June in the scientific journal Nature. Krill are shrimp-like sea creatures that feed mostly on plankton.  Since they extract their food from the water by filtering it through fine combs, they are known as filter feeders.  Krill are found in all oceans and are an abundant food source for many marine organisms.  In the polar regions, predators such as whales often rely on krill as their only consistent food source. The authors of this first piece found that a destruction of the krill population could extend undermine the Antarctic food web that relies on the presence of the small creatures.  The study launched after stacks of dead krill washed ashore at Potters Cove in 2002, lining the coast. The article’s nine authors, Verónica Fuentes, Gastón Alurralde, Bettina Meyer, Gastón E. Aguirre, Antonio Canepa, Anne-Cathrin Wölfl, H. Christian Hass, Gabriela N. Williams and Irene R. Schloss, suggest the first observed  and subsequent stranding incidents are connected to large volumes of particulate matter dumped into the ocean by melting glaciers. The high level of tiny rock particles carried by the glacial melt water may have clogged the digestive system of filter feeders like krill. The researchers conducted a series of experiments in which they exposed captive krill to water with varying amounts of particulates. The krill’s feeding, nutrient absorption and general performance were all significantly inhibited after 24 hours of exposure to concentrations of particles similar to those found in the plums of glacial runoff. Although krill are mobile creatures and can usually avoid harmful environments, exposure to the highly concentrated particles interfered with their ability to absorb nutrients from their food.  The krill became weak, which resulted in their inability to fight local ocean currents and their subsequent demise. About 90 percent of King George Island is covered in glaciers that are melting and discharging particles into the surrounding marine ecosystem, according to the article.  Similarly, an overwhelming majority of the 244 glacier fronts, a location where a glacier meets the sea, studied on the West Antarctic Peninsula have retreated over the last several decades, which suggests that high particulate count from glacial meltwater may be occurring in other parts of Antarctica. Since much of the Antarctic coast is not monitored and most dead krill sink to the bottom of the ocean, the authors caution that these stranding events likely represent a small fraction of the episodes.   In another recent study on climate change’s impacts on wildlife, scientific researchers with the Norwegian Polar Institute focus their attention on the high Arctic archipelago of Svalbard, Norway.  They found that glacial melting and changes in sea ice have impacted numerous land and sea animals in the Arctic. These shifts have the potential to influence more creatures. The study, by Sebastien Descamps and his coauthors, was published this May in...

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Photo Friday: Kronebreen Glacier in Svalbard

Posted by on May 13, 2016 in All Posts, Featured Posts, Images, Uncategorized | 0 comments

Photo Friday: Kronebreen Glacier in Svalbard

Spread the News:ShareThis week’s Photo Friday features images from a research project in Svalbard. GlacierHub has interviewed two members of the research team. Nick Hulton, a team member, explained: Kronebreen is one of the fastest flowing glaciers in Svalbard, which is an Arctic archipelago situated north of mainland Norway. The glacier drains a large ice cap, transferring ice down a narrow valley that terminates within a fjord, producing a dramatic 3 km-wide ice cliff. The CRIOS (Calving Rates and Impact on Sea Level) research group, headed by Prof. Doug Benn, has been working there for a number of years to better understand how and when ice will be transferred to the oceans, and how this will affect future global sea levels. Two CRIOS members, Penny How and Nick Hulton from the University of Edinburgh and the University Centre in Svalbard (UNIS), are using time-lapse cameras to understand how this glacier is changing and the processes that cause icebergs to break off into the ocean. The cameras take high-resolution pictures every thirty minutes, and by tracking individual features form image to image, can be used to measure how fast the glacier is flowing. Penny How, a research student in the team, added “We are currently putting 11 time-lapse cameras at Kronebreen, in an attempt to generate sequential digital elevation models using Structure from Motion (i.e. three-dimensional time-lapse).” Videos produced from these images give a good impression of how the glacier moves and can be seen here: This one gives a taste of the fieldwork involved to install these time-lapse cameras: Images from Penny How and Nick Hulton P1060518 Camera that captures images of Kronebreen glaciers IMG_0062 Installing a time-lapse camera at the front of Kronebreen glacier P1060457 All eleven time-lapse cameras that were installed in May 2016. IMG_0202 Kronebreen glacier and Kongsvegen glacier P1010929 time-lapse cameras P1030927 A section of the front of Kronebreen glacier Spread the...

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On Glaciers, Moss Become Asexual

Posted by on Apr 21, 2016 in All Posts, Featured Posts, Science | 0 comments

On Glaciers, Moss Become Asexual

Spread the News:ShareA recent study from the journal Czech Polar Reports presents interesting findings about a rarity on glaciers: moss. When glaciers have a certain amount of moisture and cryoconite—a base layer that consists of small rock particles, soot, and microbes that have accumulated on glaciers— sometimes mosses can grow on them. While it is not common to see moss on glaciers, according to a paper by Olga Belkina, a researcher at the Institute of the Kola Science Centre of the Russian Academy of Sciences, they have been found on a few glaciers in Alaska, Iceland, and Svalbard, Norway. There are some moss attributes that contribute to the mosses’ tolerance of the brutal living conditions found on glaciers. First, moss do not absorb nutrients from the substrate, the layer to which they are attached, since mosses do not have roots. They absorb water and nutrients directly through their leaves. Mosses only have rhizoids–threadlike tissues which look like roots, but function only to attach to the surface they grow on and can’t absorb water or nutrients from soil or any other substrate. Second, mosses have have the ability to adapt to a wide range of light levels, which means some types of mosses can survive under massive exposure to sunlight. Some mosses are found in the desert, and some can survive with the low intensity of sunlight found in polar areas. Although glacial areas aren’t the ideal living conditions for mosses, there are still the minimum living requirements for them to grow. There is enough moisture and little competition from other plants, allowing them to survive. One mystery of the development of mosses found on ice is that how they reproduce in such cold areas. “Failure of sex reproduction of many mosses is widespread in the high polar regions,” the study reports. The alternative is asexual reproduction. Reproduction strategies for most species fall into two categories, sexual reproduction and asexual reproduction. The offspring of the asexual reproduction process are identical to a single parent, while the offspring from sexual reproduction received genetic information from both parents. An interesting finding, according to Belkina’s study, is that Schistidium abrupticostatum, a type of moss found on the ice of Bertilbreen, Svalbard, produces gametangia–an organ which produces gametes that can fuse with another cell during fertilization to sexually reproduce. However, the mosses do not evolve into sporophytes, or the non-sexual phase of a plant.   Normally plants would alternate between a sexual phase (gametangia) and a non-sexual phase (sporophyte). During the non-sexual phase, plants grow larger and taller to produce spores through meiosis. Then the spores divide into gametes, or sex cells. A gamete from one plant can merge with another gamete, completing a set of chromosomes to start the next round of reproduction. Generally, mosses do not develop into gametophytes in harsh conditions like glaciers, even though they do in areas that are near the glaciers. Many mosses can be brought to the glaciers by wind and then settle on surface and substratum, yet only a few have the chance to create long-lived populations in such cold conditions. Each clump of moss on glaciers consists of genetically identical individuals, and the populations grow by the asexual method, which means new mosses can regenerate from a small section of existing moss plants. Spread the...

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Roundup: Kelp, Firn, and Plankton Studied in Svalbard

Posted by on Apr 4, 2016 in All Posts, Featured Posts, Roundup | 0 comments

Roundup: Kelp, Firn, and Plankton Studied in Svalbard

Spread the News:ShareEach week, we highlight three stories from the forefront of glacier news. Warming of Artic  Changes Kelp Forests’ Density and Depth From Polar Biology: “Arctic West Spitsbergen in Svalbard is currently experiencing gradual warming due to climate change showing decreased landfast sea-ice and increased sedimentation. In order to document possible changes in 2012–2014, we partially repeated a quantitative diving study from 1996 to 1998 in the kelp forest at Hansneset, Kongsfjorden, along a depth gradient between 0 and 15 m. The seaweed biomass increased between 1996/1998 and 2012/2013 with peak in kelp biomass shifted to shallower depth, from 5 to 2.5 m.” Read more about this study here.   Firn, Newly-Settled Snow on Glaciers, Stores Water From  Geophysical Research Letters: “Ice-penetrating radar and GPS observations reveal a perennial firn aquifer (PFA) on a Svalbard ice field, similar to those recently discovered in southeastern Greenland. A bright, widespread radar reflector separates relatively dry and water-saturated firn…Our observations indicate that PFAs respond rapidly (subannually) to surface forcing, and are capable of providing significant input to the englacial hydrology system.” Read more about this study on firn hydrology here.   Krill and Crustaceans Play Bigger Role in Warming Ecosystem From Polar Biology: “Euphausiid (krill) and amphipod dynamics were studied during 2006–2011 by use of plankton nets in Kongsfjorden (79°N) and adjacent waters, also including limited sampling in Isfjorden (78°N) and Rijpfjorden (80°N). The objectives of the study were to assess how variations in physical characteristics across fjord systems affect the distribution and abundance of euphausiids and amphipods and the potential for these macrozooplankton species to reproduce in these waters…Euphausiids and amphipods are major food of capelin (Mallotus villosus) and polar cod (Boreogadus saida), respectively, in this region, and changes in prey abundance will likely have an impact on the feeding dynamics of these important fish species” Learn more about these ecosystems here. Spread the...

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