- Camera Traps Reveal Secret Animal Worlds
- North America Safe From Radioactive Particles
- Sperm Whales May Have Names
Posted: 15 Mar 2011 04:00 AM PDT
<< Previous | Next >>
Asian black bear, November 2008, China. [high-resolution version]
Catching images of wild animals, especially rare ones, can be exceedingly difficult for photographers. But the Smithsonian Institution recently released more than 200,000 wildlife images captured by automated cameras hidden in forests, mountains and savannas across the globe.
Called Smithsonian Wild, the project harbors five years' worth of photographs collected in seven countries by dozens of camera traps that take photos when animals wander nearby. Some are equipped with night vision, strobe flashes and other gizmos, and some can record video.
"Each camera-trap image is a record of an animal in space and time, a record of life on Earth. To my knowledge, this is the largest database of such photos in existence," said the Smithsonian's Robert Costello, co-leader of the project. "If you create a research-grade repository that's safe and secure, it's going to be useful to researchers for a long, long time."
The scent of one person can spook shy creatures for miles around, which is when camera traps come in handy. The devices take pictures only when an animal's heat signature is detected by sensors inside a weatherproof housing. Hunters have popularized camera traps to better track and map game, but scientists use them to observe secretive animal behaviors, estimate at-risk wildlife populations and even rediscover species once thought to be extinct.
"Many animals leave virtually no sign of their existence, so camera traps are just a godsend for people like me," said wildlife ecologist William McShea of the Smithsonian Institution, co-leader of the project. "It's much better than looking at a handful of feces and wondering what dropped it. These images are like museum-quality specimens with collection dates, locations, species names and other veracious metadata."
The $29,000 pilot project used only a portion of more than a million camera-trap photos available to the Smithsonian. Costello, McShea and others hope to launch a new version that incorporates older camera-trap images and has features hat will make it easier for scientists to use and upload data. The team also wants to enlist the public's help in deploying camera traps, which cost anywhere between $200 and $600 each.
"These cameras aren't rocket science. I can train anyone to use them in under two hours, even kids," McShea said. "I'd love to have school systems deploying these in Montana, Indiana and other regions, then uploading that stuff to our database."
Aside from bolstering future research, McShea said the database is an engrossing way to learn about animals in their natural environments.
"Pictures of wild animals are usually very majestic, showing them regally, off in the distance. But camera traps bring out the good, the bad and the ugly," he said. "You can see them scratching their privates, being bit by vampire bats and even mating. It's not what you'd expect, and it makes their existence more real to me."
Te gallery above shows off some of the collection's best images and videos.
Images: Smithsonian Wild/Smithsonian Conservation Biology Institute.
Videos: Blue Raster/Smithsonian Wild/Smithsonian Conservation Biology Institute
Posted: 14 Mar 2011 10:29 AM PDT
Radioactive particles from the failing Fukushima Daiichi nuclear power station pose little immediate risk to North America, and should fall into the Pacific before reaching western shores.
Using a publicly available modeling system for airborne pollutants developed by the National Oceanic and Atmospheric Administration, Weather Underground's Jeff Masters has modeled the spread of radioactive plumes. So far, the "great majority of these runs" have seen the plumes float over the Pacific, reaching eastern Siberia and the western coast of North America in about a week.
"Such a long time spent over water will mean that the vast majority of the radioactive particles will settle out of the atmosphere or get caught up in precipitation and rained out," wrote Masters. "It is highly unlikely that any radiation capable of causing harm to people will be left in the atmosphere after seven days and 2000-plus miles of travel distance."
A press release issued March 13 by the U.S. Nuclear Regulatory Commission echoed Masters' speculation. "Given the thousands of miles between the two countries, Hawaii, Alaska, the U.S. Territories and the U.S. West Coast are not expected to experience any harmful levels of radioactivity," (pdf) they announced.
The March 11 earthquake disrupted cooling systems that pump fresh water onto fuel rods inside the plant's reactors. Even when reactors are shut down, the rods continue to produce heat. Without cooling, the rods could melt, releasing radioactive steam inside. (See Nature.com's Great Beyond blog for an excellent anatomy of the disaster.)
Repair crews are now using fire pumps to flood the plant's reactors with seawater. It's a touch-and-go process, however, and steam buildup produced explosions on Saturday and again Monday morning. A partial meltdown is now taking place. A full meltdown is possible but unlikely. In the meantime, steam from the reactors will send radioactive particles airborne.
According to the Pentagon, soldiers aboard the aircraft carrier Ronald Reagan, now sailing the Pacific, were exposed to a month's worth of radiation in one hour from particles blown out to sea. Winds over Japan blew east across the Pacific last week, and are expected to do so for the next week.
Masters noted that the Chernobyl disaster failed to spread "significant contamination" beyond 1,000 miles, and that disaster was far worse than Fukushima Daiichi has been. This release could, however, continue for months, until the fuel rods have completely spent themselves.
Image: Atmospheric simulation for radioactive particles released March 11. The blue represents particles released about 300 feet into the air, and red about 1,000 feet. The black star is the location of the Fukushima Daiichi plant./Jeff Masters and NOAA.
Posted: 14 Mar 2011 05:00 AM PDT
Subtle variations in sperm-whale calls suggest that individuals announce themselves with discrete personal identifier. To put it another way, they might have names.
The findings are preliminary, based on observations of just three whales, so talk of names is still speculation. But "it's very suggestive," said biologist Luke Rendell of Scotland's University of St. Andrews. "They seem to make that coda in a way that's individually distinctive."
Rendell and his collaborators, including biologists Hal Whitehead, Shane Gero and Tyler Schulz, have for years studied the click sequences, or codas, used by sperm whales to communicate across miles of deep ocean. In a study published last June in Marine Mammal Sciences, they described a sound-analysis technique that linked recorded codas to individual members of a whale family living in the Caribbean.
In that study, they focused on a coda made only by Caribbean sperm whales. It appears to signify group membership. In the latest study, published Feb. 10 in Animal Behavior, they analyzed a coda made by sperm whales around the world. Called 5R, it's composed of five consecutive clicks, and superficially appears to be identical in each whale. Analyzed closely, however, variations in click timing emerge. Each of the researchers' whales had its own personal 5R riff.
'This is just the first glimpse of what might be going on.'
The differences were significant. The sonic variations that were used to distinguish between individuals in the earlier study depended on a listener's physical relationship to the caller: "If you record the animal from the side, you get a different structure than dead ahead or behind," said Rendell. But these 5R variations held true regardless of listener position.
"In terms of information transfer, the timing of the clicks is much less susceptible" to interference, said Rendell. "There is no doubt in my mind that the animals can tell the difference between the timing of individuals." Moreover, 5R tends to be made at the beginning of each coda string as if, like old-time telegraph operators clicking out a call sign, they were identifying themselves. Said Rendell, "It may function to let the animals know which individual is vocalizing."
Audio: From a 2008 study of overlapping codas in pairs of sperm whales. One animal produces 1+1+3, the apparent group-level identifier. Both then produce overlapping 4R codas. After that, the first whale continues with 4R, while the other switches to 1+1+3. Finally, both make 1+1+3. The full meaning of such exchanges remains unclear, but they appear to reinforce social bonding.
Rendell stressed that much more research is needed to be sure of 5R's function. "We could have just observed a freak occurrence," he said. Future research will involve more recordings. "This is just the first glimpse of what might be going on."
That individual whales would have means of identifying themselves does, however, make sense. Dolphins have already been shown to have individual, identifying whistles. Like them, sperm whales are highly social animals who maintain complex relationships over long distances, coordinating hunts and cooperating to raise one another's calves.
Sperm-whale coda repertoires can contain dozens of different calls, which vary in use among families and regions, as do patterns of behavior. At a neurological level, their brains display many of the features associated in humans with sophisticated cognition. Many researchers think that sperm whales and other cetacean species should be considered "non-human persons," comparable at least to chimpanzees and other great apes.
Compared to primates, however, studying the behaviors and relationships of whales is extremely difficult. They don't take well to aquariums, and observations in the wild take place on their aquatic terms.
What's been observed so far are just "the crude behavioral measures we get by following them in a boat," said Rendell. "I'd argue that there is probably a vast amount of complexity out there in sperm whale society that we have yet to understand. As we get to know more about them, we're going to continue to reveal complexities that we didn't anticipate."
Image: NOAA. Audio: Luke Rendell.
Citation: "Individually distinctive acoustic features in sperm whale codas." By Ricardo Antunes, Tyler Schulz, Shane Gero, Hal Whitehead, Jonathan Gordon, Luke Rendell. Animal Behavior, Feb. 10, 2011.
|You are subscribed to email updates from Johnus Morphopalus's Facebook notes |
To stop receiving these emails, you may unsubscribe now.
|Email delivery powered by Google|
|Google Inc., 20 West Kinzie, Chicago IL USA 60610|