People believed the myth about the suicidal tendencies of lemmings for years before it was debunked. Though lemmings got a bad rap for a long time, bizarre mass deaths do occur fairly regularly in the natural world. Sometimes the deaths seem inexplicable, and other times scientists can figure out the cause. As you'll see below, nature doesn't always nurture our winged, webbed, and fuzzy friends.
1. Sadly, this past week saw the death of over 500 penguins in southern Brazil. The birds were migrating from Argentina, but appeared well-fed, uninjured, and unstained by oil, according to biologists. The cause of death is unknown, but under investigation.
(Frederic J. Brown/AFP/Getty Images)
2. In 2005, thousands of Humboldt — or jumbo — squid washed up on California's shores. The weirdest part? Scientists couldn't figure out why. William Gilly, a biologist from Stanford University, told National Geographic that the deaths may have been caused by the squid spending too much time in warm water or from ingesting something toxic. Poor "Red Devils."
(David McNew/Getty Images)
3. The first cases of bats with "white nose syndrome" were reported in 2006. This syndrome has killed over a million bats in the US and Canada. So what's up with the white nose? The look comes from a fungus that plagues hibernating bats on their noses and mouths, preventing them from sleeping and causing them to wander far from their caves and use up their energy.
(Daniel Mihailescu/AFP/Getty Images)
4. An enormous number of wildebeasts perished in the fall of 2007 in Kenya's Mara River, but the exact death toll is uncertain. Conservationist groups on the scene said that 10,000 of the wildebeasts met their mamalian demise, while the Kenya Wildlife Service maintained that only 5,000 of the beasts died. How did it happen? The animals attempted to cross the river, a regular occurence, but found that they could not make their way up the especially steep embankment on the other side. The result was a deadly pileup with no possiblity of escape.
(Roberto Schmidt/AFT/Getty Images)
5. Free Willy fans beware, this is a sad one. Late in 2008, 60 pilot whales were found dead on the coast of Tasmania.
It gets worse.
A week later 150 more whales washed ashore.
Early in 2009, nearly fifty sperm whales died on a sandbar in Tasmania.
Almost 200 more pilot whales and a few bottleneck dolphins washed up on that same coastline a few months later. Rescue efforts saved about 50, but scientists were puzzled by the beached whale epidemic.
(Tony Ashby/AFP/Getty Images)
6. ABC reported last year that in 2010 alone there were eight documented mass "die-off events" of 1,000 or more birds. People began calling it the "aflockalypse," and, even though scientists dispelled any end-of-the-world notions, the name is understandable. Bird deaths occurred in the Philippines, New Zealand, the UK, Haiti, and in several US states. Check out a map of mass bird deaths from 2000 to 2010 here.
(Mario Tama/Getty Images)
7. Four calling birds, three french hens, two turtle doves...no, wait, a thousand turtle doves? That's how many seemed to fall from the sky in northwestern Italy in early 2011. The birds landed everywhere — in backyards, in the street, and on top of cars — but nearly all had a mysterious blue stain on their beaks. An autopsy revelead that the doves had gorged themselves on sunflower seeds from a nearby factory which may have lead to deadly indigestion. That would cause the blue beaks, a sign of poisoning or lack of oxygen.
(Miguel Rojo/AFP/Getty Images)
8. Fish are sensitive creatures, it turns out, at least when it comes to temperature. In 2011, thousands of fish floated to the top of the Chesapeake and gave everyone quite a scare. Scientists again dispelled apocolypse fears and named particularly chilly temperatures as the cause of death. That's a cold we don't want to catch.
(Win McNamee/Getty Images)
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See a Google map of mass animal deaths