National Geographic Today
On a chilly morning in late August, out in the deep waters of Chatham Strait near Juneau, Alaska, humpback whales are hungry for herringtheir impatient fountains of whale breath hanging suspended in the air. Standing on a small boat nearby waits Fred Sharpe of the Alaska Whale Foundation, who has studied these creatures for 15 summers. This year Sharpe is hoping to capture something that no one has ever seen beforea whale's eye view of mealtime.
Using "Crittercam"a camera painlessly mounted on the whale's head via a suction cuphe hopes to witness lunge, or bubblenet feeding, which is an unusual cooperative hunting technique used by humpback whales.
It all starts when a pod of whales dive deep under a school of fish, form a circle, and blow their breath out simultaneously, forming a net of bubbles. Within the ring each humpback has a specialized task.
Some blow the bubbles, while others go down and herd the prey towards the surface. Another group screams "incredibly beautiful and haunting sounds" in order to concentrate the prey and force them up towards the surface into the confines of the bubble net, Sharpe said.
"And they all get together in the group and they come charging up through this tunnel of bubbles, almost like missiles coming up through a silo, and then engulf the prey into their huge mouths at the surface," Sharpe said. "It's an incredible feeding event."
The technology used to spy on feeding time is more than just a video camerait is a miniature laboratory and television studio.
There is a tiny camera, sensors that measure water temperature, depth, and speed and even a microphone. Then the package is wrapped in a waterproof housing and readied for a ride on the back of a humpback. The Crittercam was invented by National Geographic producer Greg Marshall who, while swimming in a coral reef off Belize in 1986, eyed a remoraa parasitic fishattached to the side of a shark. He envied the remora's knowledge of the shark's life and designed a camera that could be attached to marine mammals in much the same way. Clinging to marine creatures, the Crittercams have been use to reveal underwater worlds previously hidden from humans.
Sharpe's team leaves the larger research vessel in a rubber dinghy, and zips and bobs around on the choppy water trying to get close to the enormous animals. One member of the team holds out a long pole attached to the Crittercam. Just one flick of a flipper or fluke in the wrong direction could send the entire team, and its equipment, tumbling into the frigid waters.
"We do this for five hours at a time, just to get to the point where we are actually close enough [to attach the camera]," Birgit Buhleier said. The team has had several close calls.
"I felt the fluke kind of coming up and scraping along my back and me over the head and then the next thing was just this water splashing over the boat," Buhleier laughed. "We all got baptized."
After hours of cold and wet, the team managed to sneak behind one of the whales, reach out the pole and successfully position the camera on a huge head.
The video that emerged is greenish and grainy but to these researchers it is pure gold. Through the murky water, the scientists see what the whale sees: diving to the bottom, blowing the bubble net, and rocketing to the surface for a huge mouthful of herring.
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