February 19th, 2018
Tagging minke whales will help scientists learn more about how they forage and their favorite feeding spots(Credit: Ari Friedlaender/WWF-Aus)
Advanced cameras, particularly those attached to drones, have become invaluable tools for scientists studying marine life, but one creature that has remained relatively elusive is the polar-dwelling minke whale. For the first time ever, scientists have managed to slap a camera onto the mammal's back as it swam through the icy waters of Antarctica, surprising researchers with its speed and seemingly insatiable appetite.
There are actually two types of minke whale, the northern minke and the Antarctic, or southern, minke. At 8 or 9 m in length (26 to 30 ft) the minkes are the second smallest of the baleen whales, larger only than the pygmy right whales.
Minkes get their sustenance from krill or small fish, which, like their relatives, they filter through special feeding plates called baleen in a process called lunge feeding. Blue or fin whales will draw in massive amounts of water when lunge feeding, even equal to the volume of their entire bodies, but evidence of the feeding habits of minke's has been harder to come by.
"There are so many unknowns with these animals," said Dr Ari Friedlaender, marine ecologist at the University of California, Santa Cruz, lead scientist on the research. "We know that they associate with sea ice, but we really know nothing about their behavior underwater."
Solving that involved some endeavor and quite a bit of luck. Friedlaender and his team ventured to Antarctica where they encountered a particularly friendly minke, which hung around the boat, rolling over and breaking through the surface of the water. This is when the researchers seized the moment, using a long pole to put a camera on its back, something Friedlaender described as "one of the most memorable moments of my scientific life."
And the good fortune didn't stop there. The camera sticks to the animal with suction cups, and actually slid down the body of the whale but managed to stay in place. This accidental repositioning of the camera meant that it caught footage it otherwise wouldn't have and filmed the whale's throat expanding as it fed.
"The video showed the tagged minke moving at up to 24 kilometers per hour (15 mph) as it accelerates to feed," says Friedlaender. "We could see individual feeding lunges and the expansion of the throat pleats as they filled with prey-laden water. What was remarkable was the frequency of the lunges and how quickly they could process water and feed again, repeating the task about every 10 seconds on a feeding dive. He was like a Pac-Man continuously feeding."
Aside from an unprecedented look at the behavior of these animals, tagging the minke whales will help scientists learn more about how they forage and their favorite feeding spots. This type of information can in turn guide policy around fishing and protected marine areas in the Antarctic, an important part of the effort to conserve the area's biodiversity.
You can tune into the whale-cam below.
Source: World Wildlife Fund