First Fishing Bat Discovered in Europe

The long-fingered bat is the first bat species inEuropeknown to catch and eatfish, scientists say.

Weighing around 0.3 ounce (9 grams) and measuring just over 1.5 inches (42 millimeters), the minuscule bat was long thought to feed only oninsects. Scientists were therefore surprised to discover fish bones and scales in the bat's feces in 2003.

(Related:"'Whispering' Bat Evolved to Trick Prey.")

To figure out whether the bats were actively fishing, Joxerra Aihartza of theUniversity of the Basque Countryin Bilbao, Spain, and colleagues began monitoring the animals' feeding behavior using small radio tracking devices.

Recently the team captured video of the bats catching live fish.

"They fly low over the water and catch surface-feeding fish, such as the mosquitofish, with their claws,"Aihartza said.

Europe's Fishing Bat a Species at Risk

A handful of bats worldwide are known to catch fish, including South America's fisherman bat. (Watchvideo of the fisherman bat at work.)

As far as Aihartza and colleagues know, the long-fingered bat is the only bat in Europe with this skill.

Despite its proficiency as a fisher, the long-fingered bat mostly eats aquatic insects, the team said. The bats likely turn to fishing when nearby bodies of water start to dry out, forcing more fish to swim near the water's surface and making them easier to catch.

(Related:"Extinct Walking Bat Found.")

The long-fingered bat can be found foraging over wetlands and waterways—including canals and reservoirs—across its range, which hugs the Mediterranean coasts of Morocco, Algeria, and Europe, stretching into Lebanon, Jordan, and Iran. (See aMediterranean map.)

Major threats to the species' survival include water pollution, dam construction, and wetlands loss, according to the International Union for Conservation of Nature.

"Habitat availability is a real problem for this bat, and in Spain it is an endangered species,"Aihartza said.

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How Shark Scales Give the Predators Deadly Speed

Ashark's bite may kill prey, but it's the teeth covering its body that make the fish such a good hunter, new research suggests.

Sharks are covered in flexible scales—nearly invisible to the human eye—that are made of the same material as teeth. The scaly hide serves as both a suit of armor and a means of streamlining movement, according toAmy Lang, an aerospace engineer at the University of Alabama.

For instance, previous research had suggested that a shark can"bristle"or otherwise manipulate its scales to change its direction mid-sprint—agility that's crucial for capturing fast-moving prey such as tuna.

(See"Great White Breaks Distance, Speed Records for Sharks.")

But a recent experiment revealed that sharks don't actively move their scales, which are loosely embedded in the skin via rubber band-like tendons, Lang said.

Instead, the structures bristle when water flowing around the shark"detaches"from the fish's aerodynamic body.

The way the scales turn helps reduce the water's drag on the speeding shark. (Solve a shark jigsaw puzzle.)

Lang compared the phenomenon to dimples on a golf ball, which enable the ball to travel farther in the air.

"Imagine a stream of flow going over the ball,"she said."You get a low-velocity wake behind the body, but the dimples help to decrease the size of the wake—that's what we think the scales are helping to do with the shark."

Mako Shark's Scales Built for Speed

Lang partnered with a team of biologists to study the shortfin mako, a relative of thegreat white shark, in the lab.

One of the fastest and strongestfishin the ocean, shortfin makos can reportedly leap up to 40 feet (12 meters) in the air. (See shark pictures.)

Combining lab observations of the shark's scales with computer models, the team discovered that a shortfin mako's scales differ in size and flexibility over its body.

For instance, the most tapered—and thus most movable—scales were found behind the gills and on the sides of the body. Scales in these areas can bristle up to angles of 60 degrees or more from the skin, according to Lang.

These are also same areas where water flow would separate from the shark and create drag.

Overall, sharks' 400 million years of evolution for strength and speed may someday inspire better designs for machines that are prone to drag, such as aircraft, Lang noted.

Research presented November 23 at theAmerican Physical Society's Division of Fluid Dynamicsmeeting in Long Beach, California.

National Geographic News

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Pictures: Best Underwater Views of 2010 Announced

A diver explores a continental trench in Silfra,Iceland, in 2010. The picture won top honors in the"Divers"category of the fourth annualDeep Indonesia International Underwater Photo Competition, whose winning photos were released to the press earlier this month.

The competition awarded U.S. $35,000 in seven categories for the most"stunning"underwater photos taken around the world in 2010, according to a press statement. Judges included professional underwater photographers and magazine editors.

(See relatedpictures:"Best Aquatic Views From 2009 Contest."

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Pictures:"Mr. Burns" Toad, More New Amphibians Found

Nosing around for"lost"amphibianspecies in western Colombia in September, scientists stumbled across three entirely new species—including this beaked toad."Its long, pointy, snoutlike nose reminds me of the nefarious villainMr. BurnsfromThe Simpsonstelevision series,"expedition leader Robin Moore said in a statement released Tuesday.

The unnamed, 0.7-inch-long (2-centimeter-long) toad is"easily one of the strangest amphibians I have ever seen,"added Moore, an amphibian-conservation specialist forConservation International.

The toad also has an odd reproductive habit: skipping the tadpole stage. Females lay eggs on therain forestfloor that hatch into fully formed toadlets.

In addition to the never before seen amphibians pictured here, the unprecedented global effort to rediscover amphibians presumed extinct—led by Conservation International and the International Union for Conservation of Nature'sAmphibian Specialist Group—hasyielded three species rediscoveries, including aMexicansalamander not seen since 1941, a frog fromCôte d'Ivoirenot seen since 1967, and a frog fromDemocratic Republic of the Congonot seen since 1979. (Seepictures:"Ten Most Wanted 'Extinct' Amphibians.")

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Large,"Glamorous" New Glowing Squid Species Found

A large new species of deep red, glowing squid has been discovered living near undersea mountains in the southern Indian Ocean, scientists announced Monday.

At about 28 inches (70 centimeters) long, the as yet unnamed species is relatively big—though other squid can reach as long as 65 feet (20 meters), some species are barely three quarters of an inch (1.5 centimeters).

(See"Colossal Squid a Soft, Sluggish Drifter.")

The new species belongs to Chiroteuthidae, a group of slender squid in which light-producing organs run in the family. (Related:"Colossal Squid Has Glowing 'Cloaking Device,' Huge Eyes.")

"It's thought that this particular group of squid actually uses bioluminescence to lure in prey,"which are thought to include small fish and crustaceans, saidAlex Rogers, a conservation biologist at the University of Oxford in the U.K.

The new squid is just one of more than 70 squid species observed during a six-week research cruise that began in September 2009 but whose results are only now beginning to be released.

"In a single expedition, we sampled about a fifth of all the world's squid species that are known to date,"Rogers said."That's really a staggering diversity of squid to sample in a single trip."

Most of the squid observed were already known to science, but, in addition to the blinking beast above, a few are thought to be completely new species.

"We think we have more than one new species of squid,"Rogers said."This just happens to be the biggest and most glamorous one."

(Pictures: Giant Squid Get Extreme Plastic Surgery.)

Mountains of Food for Squid and Other Species

The aim of the research cruise, led by theInternational Union for Conservation of Nature(IUCN), was to document the abundance of marine life associated with underwater mountains. (Read more about the project on National Geographic'sMission Blue website.)

Scientists estimate there are tens of thousands to hundreds of thousands of seamounts—undersea mountains rising more than 0.6 mile (1 kilometer) high—scattered throughout the world's oceans.

On the single 2009 expedition alone, Rogers said,"We got a tremendous variety of ... animals, including over 200 fish species and a large collection of crustaceans as well."

One reason seamounts appear to be such biological hot spots is that the submerged peaks act as food traps for squid and other creatures living on or around them.

The undersea mountains often block the daily vertical migration of plankton and other microorganisms from the ocean's surface to its depths, Rogers explained.

"The animals,"he said,"can just sit on the seamounts and feed on what drifts by."

More:Alien-like Squid With 'Elbows' Filmed at Drilling Site>>

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Pictures: Oldest Dinosaur Embryos Show"Big Surprises"

The sharpest look yet at the oldest known dinosaur embryos (pictured, one of the eggs and its inhabitant) has revealed some"big surprises,"a scientist says.

For one thing, the 190-million-year-old babies ofMassospondylus—a two-legged dinosaur that preceded the well-known sauropods, such asDiplodocus—do not resemble their parents, according to study co-authorHans-Dieter Sues, a paleontologist at the National Museum of Natural History in Washington, D.C. (See more dinosaur-embryo pictures.)

The 8-inch-long (20-centimeter-long) youngster, for example, had long front legs for walking on all fours, and its overall body proportion—such as a short snout—made it"look like a dwarf version of a sauropod dinosaur,"the largest animals to walk Earth. (See a sauropod picture.) The babies would have lost these traits as they matured.

The discovery suggestsMassospondylushad characteristics that"foreshadowed"the later look of the sauropods, he said. (See"New Strong-Handed Dinosaur May Shatter Assumptions.")

—Christine Dell'Amore

The oldest-dinosaur-embryo research appears in the November issue of theJournal of Vertebrate Paleontology.

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Bats Crash More Often When They Use Vision

Being blind as a bat apparently has its benefits: Wild bats that use their vision to fly short distances are more likely to crash into objects, new research says.

Bats can navigate both visually and acoustically, by sending out sound waves and listening for echoes bouncing off objects—including prey. Bat vision is generally known to be sharpest in dim light, and to get worse the brighter it gets.

(Related:"'Whispering' Bat Evolved to Trick Prey.")

For the new study, scientists set up an obstacle course near an abandoned mine inOntario, Canada, where little brown bats often gather.

The team manipulated three types of light conditions—dark, dim, and bright—and observed how little brown bats flying through the course behaved. The results showed that bats primarily relied on their vision to navigate the well-illuminated course—even though their reliance on vision made them more prone to crashing.

In the obstacle course, the team used fabrics of three different visibilities—a clear fabric, an opaque fabric, and a reflective fabric. If the bats were mostly using their sonar, they should have detected all three. But the bats did not sense some fabrics—such as the clear one—suggesting the animals were depending more on their vision, the scientists noted.

The study is among the first experiments to confirm such behavior in wild bats, according to study co-author Dara Orbach, formerly a graduate student at theUniversity of Western Ontarioin Canada. (Seeflying-bat pictures inNational Geographicmagazine.)

Past experiments have shown that blindfolded, captive Indiana bats ran into windows less often than bats that could see, and that little brown bats flying through a lab obstacle course crashed more often when the lights were turned up.

Hormone Switch Changes Crash Rates?

It's unknown why bats use their vision to their detriment. But the research also turned up a tantalizing clue: Midway through the study, when the bats' hormones shifted, so did their the crash stats.

"That was the really unexpected part,"Orbach said."We know there are two phases {of bats' preparation for hibernation}. During the first phase of swarming, during the month of August, they're flying around to different hibernation sites. And then there's this distinct day—at least at our field site—{when} there's a switchover."

(See"'Drunk' Bats Fly Right—Discovery Surprises Scientists.")

After that turning point, the bats changed their eating habits, became sleepier during the day—like a temporary hibernation—and began"promiscuous"mating, Orbach said.

What's more, themammals' behavior reversed: They began crashing more in the dark than in the light.

The switch between bats' behavior and the collision rates match up nearly perfectly.

"We don't know for sure, but our suggestion is that the way bats are using vision could correspond to their different needs"at different times, Orbach said.

"There seems to be this relationship that corresponds to hormonal or physiological changes in the bat."

The bat-vision study appeared November 9 in the journalPLoS ONE.

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