Flora and Fauna
(Nina Kristiansen/Science Nordic, 30 March 2012) -- The notion about Arctic organisms shutting down during winter has been taken for granted until some tiny copepods proved differently. “We don’t know so much about life up there in the Arctic waters during winter because our research voyages are conducted during the summer season,” says Elisabeth Halvorsen, a marine system ecologist at the University of Tromsø. A year-round monitoring station on Svalbard made some observations that caught the attention of scientists. Certain activities were continuing during long Arctic night. This motivated Halvorsen to join in on the research voyage “The Polar Night Cruise” in January this year. It’s rare for researchers to visit distant arctic regions at that time of year. “We were lucky. The extreme storms dubbed “Dagmar” and “Berit” kept the sea from icing over fairly far north,” says Halvorsen. She found that it was far from all peace and quiet and hibernation up there. “On the contrary, we witnessed a great deal of activity. The object of my studies, the copepod Calanus hyperboreus, was already in spring vigour in January.” C. hyperboreus is the largest of three species of the calinus genus of copepods found in Arctic waters. But it isn’t big, only four or five millimetres long. Despite its modest size, the C. hyperboreus is a vital source of food for fish and seabirds. It is most predominant in the Greenland Sea and the Arctic Ocean.
Posted 30 March 2012; 4:20:26 PM. Permalink
(Norwegian University of Science and Technology press release via Eurekalert.org, 29 March 2012) -- It's never been easy to be a polar bear. They may have to go months without eating. Their preferred food, seal, requires enormous luck and patience to catch. Add to that the melting of Arctic sea ice due to climate change, and the poisoning of the Arctic by toxic chemicals, and it's easy to see why polar bears worldwide are in trouble. Among all the bad news, however, comes one possible bright spot. In a study of PCBs in polar bear cubs in Svalbard, researchers from the Norwegian University of Science and Technology (NTNU) have found that blood levels of PCBs and related contaminants in polar bear cubs appear to have dropped by as much as 59 per cent between 1998 and 2008. At the same time, levels of these contaminants in their mothers were as much as 55 per cent lower over the same period. "The levels of PCB compounds in blood samples from females are on the decline," says Jenny Bytingsvik, a biologist at NTNU who is completing her doctoral dissertation on the findings. "For newborn, vulnerable cubs, this is a very positive trend. Reduced levels of PCBs in the mother bears' blood mean that there is also less contamination in their milk. Even though the PCB levels we found are still too high, this shows that international agreements to ban PCBs have had an effect."
Posted 30 March 2012; 2:33:35 PM. Permalink