  Deep in the rainforests of Belize, after the last rays of sunshine have disappeared, a swift and stealthy hunter takes to the air over rivers, ponds and lakes. The quick movements of this creature, the greater bulldog bat, also commonly known as the fisherman bat, are almost impossible to follow with the naked eye in the dusky light. Only small splashes on the water's surface indicate that this animal is doing what it does best — fishing. But the filmmakers who traveled to Belize to capture this unique behavior for Life had technology on their side and a way to literally slow time.
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Watch "Bulldog Bats Fish at Night"
SLOWING DOWN A SPLIT SECOND
The
greater bulldog bat (scientific name
Noctilio leporinus) counts itself among a handful of bat species that feed on something other than insects. So named for its large and swollen lips, reminiscent of a bulldog's — this flying mammal catches fish from the water sources in Central and South America with amazing speed and precision. It speeds through the air at more than 40 miles per hour (64 kilometers per hour) and uses echolocation (or the ability to locate objects such as prey with sound waves) to find fish below the water's surface.
"What made trying to film the [bat] sequence possible was the use of very, very high-speed cameras that allowed us to slow the action down dramatically," said Adam Chapman, producer of the "
Hunters and Hunted" episode of
Life. "We would have really struggled to portray that kind of behavior [without this technology]. The cameras are extraordinary."
As Chapman describes it, the camera used to film the bats taking their nightly meal is essentially a massive hard drive, which can record a huge number of still images per second. Those images can then be downloaded and strung together to create incredible slow-motion sequences.
To give some perspective, most filming is done at 24 or 25 frames per second. The camera used in Belize captured the
greater bulldog bats at 2,000 frames per second, slowing the behavior down by an astounding 83 times. "This gives you time to see in incredible detail the actual intricacies of what the bat is doing, from the way it's opening its mouth to call, to the way the skin on its wings is rippling, to the last moments as it comes to take a fish and it's almost gliding," said Chapman.
Although the camera slows down the action on film, it didn't impede the bats in reality. "The thing about the bats was that we didn't realize just how fast they are," said Chapman. He and his crew used ultrasonic bat detectors to give themselves some advance warning as the bats approached. They set the camera to film eight-second sequences, four seconds both before and after pushing the camera's record button. They then waited to push the "trigger" until they saw a splash in the water where a bat had landed, hoping to capture the four seconds before the catch and the four seconds following it.
But the crew had to contend with other challenges, aside from the bats' incredible speed. The high-speed cameras weren't designed for the hot, humid rainforests of Belize, and the first camera actually "gave up the ghost," as Chapman put it. A second camera had to be flown in to salvage the three-week shoot. Even then, the crew had to battle the climate and an endless parade of bugs that seemed to want to climb into the camera's every nook and cranny. And, of course, there was the challenge of filming behavior that takes place in the pitch dark of night.
Continue: Lighting the Night
