Chinese cruiser Zhiyuan ca.1894
Chinese cruiser Zhiyuan ca.1894

19th Century Chinese cruiser Zhiyuan identified

The shipwreck was first discovered in 2013. It was first code-named "Dandong No.1" and has been tentatively identified as the Cruiser Zhiyuan.

On 17 September 1894, during Battle of the Yalu River - the largest naval engagement of the First Sino-Japanese War, involving ships from the Imperial Japanese Navy and the Chinese Beiyang Fleet - the Zhiyuan came under attack from Japanese cruisers. It was hit in the bow by a Japanese shell after which the Chinese cruiser rapidly sank with the loss of 245 officers and crewmen out of a complement of 252 complement.

Blue whales optimize foraging efficiency by balancing oxygen use and energy gain as a function of prey density
Blue whales optimize foraging efficiency by balancing oxygen use and energy gain as a function of prey density

Blue whales' meal planning is complicated

Feeding performance of blue whales vary wide as a function of prey density and distribution, according to new research just published in Science Advances. Because rorqual whales are air-breathing divers that exhibit a high-cost feeding mechanism, they are under considerable pressure to optimize their foraging success by weighing oxygen use against possible energy gain. Blue whales, the researchers have found, follow a complex strategy of switching from conserving oxygen when prey quality is low, to intense foraging at the expense of oxygen when prey quality is high.

Blue whale sighted at Gulf of Alaska.

Feeding strategies of blue whales revealed

Scientists studying blue whales off California's coast discovered that blue whales modify the intensity of their efforts when hunting krill in order to conserve energy.

"We found that blue whales have a complex strategy of switching from conserving oxygen when prey quality is low, to intense foraging at the expense of oxygen when prey quality is high," said Elliott Hazen, research ecologist at the U.S. NOAA Fisheries' Southwest Fisheries Science Center and lead author of the study.