Japan made some progress in stabilizing the Fukushima Daiichi nuclear plant over the weekend, cooling down two of the tsunami-damaged reactors and restoring the water pumps at two others. But reactor No. 3 continued to overheat, forcing the Tokyo Electric Power Co. to evacuate workers as smoke seeped out. Officials had previously said radioactive steam was building up inside the reactor, although the smoke's source wasn't immediately clear. "We are checking the cause of the smoke," a nuclear safety official told reporters, adding that no radiation spike was detected at the plant. Meanwhile, key machinery at another fallen reactor was found to need repairs that could take two to three days.
But perhaps the biggest immediate fear in Japan isn't from airborne radiation — it's from nuked food
. Officials have detected high levels of radiation in certain crops and livestock grown near the Fukushima Daiichi plant, leading them to pass targeted bans aimed at limiting the items' spread. The government announced a ban on all shipments of milk from Fukushima Prefecture and spinach from Ibaraki Prefecture, following new cases of above-average radiation in milk and several vegetables. Relatively high levels also turned up in spinach from Tochigi and Gunma prefectures , canola from Gunma, and chrysanthemum greens from Chiba Prefecture. This suggests the food-safety situation in Japan is "more serious" than it first seemed, an official with the World Health Organization tells CNN. "Quite clearly, it is not what we thought in the early stages. It is more serious," says WHO spokesman Peter Cordingley. "We have seen Japanese people in grocery stores paying close attention to where their produce is coming from, and we think this is a wise practice."
Radioactive iodine was found in milk from four locations in Fukushima, ranging from roughly 20 percent above the safe limit to more than 17 times that amount. Ibaraki, a major vegetable-producing hub in Japan, also saw spinach from 10 locations test anywhere from 5 percent over the acceptable limit to more than 27 times the threshold. Smaller amounts of cesium were also detected in both prefectures. "It doesn't look like a short-term issue," one Tokyo resident tells CNN. "I'm definitely concerned about the food that is going to be shipped out from now. I'm definitely thinking about it."
Knut, the world-famous polar bear at a Berlin zoo, died Saturday, the AP reports. The beloved bear was just 4 years old, but that time was packed with media adoration after Knut was rejected by his mother at birth. Zoo keepers hand-raised Knut from that point, nurturing the cub as well as its global marketing phenomenon, including a Vanity Fair cover shoot with Leonardo DiCaprio, an Italian girlfriend named Gianna
, and a barrage of merchandise such as postcards, key chains, candy and stuffed animals.
Knut reportedly died alone in his compound at the zoo, although the cause of death wasn't immediately clear. "He was by himself in his compound, he was in the water, and then he was dead," bear keeper Heiner Kloes tells the AP. "He was not sick; we don't know why he died." A post-mortem analysis will be conducted Monday to determine the cause of death, Kloes adds. Around 600 to 700 people were on hand at the time to see Knut die, the AP reports.
In addition to serving as a likable ambassador for his troubled species, Knut was also an economic boon to Berlin. Born on Dec. 5, 2006, he was introduced to the public 15 weeks after being rejected by his mother, and attendance at the zoo has roughly doubled in the four years since. "We all held him so dearly," says Berlin Mayor Klaus Wowereit. "He was the star of the Berlin zoos."
King crabs are invading Antarctica, the Washington Post reports, raising concerns that a vast ecosystem of soft-bodied marine animals could be wiped out by the hard-shelled, sharp-clawed army. A robot sub made the discovery in Antarctica's frigid coastal waters, capturing images of king crabs up to 10 inches long marching into a habitat that hasn't seen anything like them in the past 40 million years. "There were hundreds," researcher Sven Thatje tells the Post. "Along the western Antarctica peninsula, we have found large populations over 30 miles. It was quite impressive."
There are 13 species of king crabs around the world, concentrated in the deep waters off Alaska and Russia, as well as in the Southern Ocean off New Zealand, Chile and Australia. But they've never managed to cross the Southern Ocean to the Antarctic coast before, simply because the water was too cold. In their absence, bottom-dwelling marine animals such as mussels, sea urchins and brittle stars evolved without any defenses against pinchy predators. The crabs are apparently now able to invade Antarctica, however, because of rising temperatures: The air there has warmed almost 11 degrees Fahrenheit since the 1950s, while the average ocean temperature has risen by one degree over the same period.
A lack of heat has kept more than just crabs out of Antarctica for eons: There are no sharks, rays or other bony-jawed fish, thanks to a clockwise flow of cold water called the Antarctic circumpolar current. This allowed the animals that do live there to dispense with energy-wasting body parts like shells or claws, since they rarely needed them. "The Antarctic shelf communities are quite unique," Thatje says. "This is the result of tens of millions of years of evolution in isolation."
If you're worried about wind turbines killing wild birds, a new study in the Journal of Ornithology points out there's a much broader threat lurking in the shadows: pet cats. "Cats are way up there in terms of threats to birds — they are a formidable force in driving out native species," Smithsonian biologist and study co-author Peter Marra tells the New York Times. "They are like gypsy moths and kudzu — they cause major ecological disruption."
Studying baby gray catbirds in the suburbs of Washington, D.C., the researchers found that nearly 80 percent of the chicks were killed by predators, and 47 percent of those died at the paws of house cats. Death rates were especially high in neighborhoods with large cat populations, the study found. Up to 500 million birds are killed every year by cats, according to the American Bird Conservancy, with about half killed by feral cats and half by roaming pets. That dwarfs the estimated 440,000 birds killed by wind turbines each year, according to U.S. Fish and Wildlife Service statistics (although that number is expected to creep up to 1 million by 2030 as more wind turbines are built across the country).
"I hope we can now stop minimizing and trivializing the impacts that outdoor cats have on the environment and start addressing the serious problem of cat predation," says Darin Schroeder, the conservancy's vice president for conservation advocacy. As Marra argues, wind turbines are unfairly targeted as bird killers, while hordes of house cats roam the country unchecked. Wind power can be "bird smart," he says, with a little planning to make sure the turbines aren't located in high-traffic flight paths. "I'm excited about wind; we just have to be careful where and how we put the turbines," he says.
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Photo (spinach leaves): David Wasserman/Jupiter Images
Photo (Knut the polar bear in 2007): ZUMA Press
Photo (king crab): National Science Foundation