For the first time ever, a team of scientists working in Antarctica have successfully captured remarkable evidence of how a minke whale feeds. Recently, these scientists had attached a camera to a minke whale, which captured some wonderful footage of this creature in its feeding areas in Antarctica.
The camera attached to the animal is one of the three “whale cams” funded by the World Wildlife Fund (WWF) Australia. Researchers attached it to whale’s body using non-invasive suction cups. These cups remain attached to the body for 24-48 hours and then automatically fell off the body.
After the researchers attached the camera to the minke whale, it slid down the side of the animal after some time, but luckily stayed attached to the body, and eventually captured some incredible footage that would not have been possible with the original camera placement, according to the team. The video shows the minke’s throat expanding as it moves through the water and feeds.
Minke is among the poorly understood whale species. The minke whale is a type of baleen whale and can grow up to nine meters in length. They are the second smallest baleen whales (only the pygmy right whale is smaller). There are two species of minke whale: common (or northern) minke whale and the Antarctic (or southern) minke whale. Northern minke whales are distinguished from other whales by a white band on each flipper. These creatures usually live for 30–50 years.
Minke whales consume small fish or krill by filtering them out of the water using specialized feeding plates, known as baleen. This method of eating is known as lunge feeding. When larger whales (like fin or blue whales) lunge feed, they take in large volumes of water and take up to a minute to process each gulp.
“What’s amazing to me is how fast the minke swims and how quickly it can feed,” said Dr. Ari Friedlaender, an associate professor from the University of California Santa Cruz and lead scientist on the research.
“The video showed the tagged minke moving at up to 24 kilometers per hour as it accelerates to feed. 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.”
According to Dr. Friedlaender, the relatively small size of minke whales helps it maneuver through the sea ice. Moreover, their ability to feed quickly has enabled this species carve out a niche in Antarctica.
“Larger whales try to avoid ice because they can’t maneuver as well so they feed in open water. They also need dense patches of krill or fish to offset the energy required to accelerate, lunge, and process large gulps of water.”
By attaching a camera to their backs, scientists have already learned that minkes move much faster than other whales while feeding https://t.co/vXf3441TdX
— National Geographic (@NatGeo) February 25, 2018
“But minkes can feed among the ice because of their size. Interestingly, their small size also decreases the energy it takes to feed, and thus they can take advantage of less dense patches of prey,” he said.
For Dr. Friedlaender, deploying a camera tag on a minke was “one of the most memorable moments” of his scientific life.
Chris Johnson, senior manager of WWF’s Antarctic Program also joined Dr. Friedlaender on the trip that was completed on OneOcean Expeditions vessel.
“This animal just kept hanging around the boat, rolling over on its side, just as fascinated by us as we were by him. He then really put on a show breaching repeatedly. It really looked like he was having fun,” Mr. Johnson said.
Piggybacking a minke whale. In a breakthrough experience, camera-tagged Antarctic minke whale shares lunch hour with scientists. https://t.co/7izYmcrc65. @WWF_Australia, #SouthernOcean, #minkewhale #antarctica pic.twitter.com/6LZc9B3CUM
— Antarctic and Southern Ocean Coalition (@AntarcticaSouth) February 21, 2018
Sea ice is vital for minke whales as it provides them a place to feed and hide from killer whales. However, climate change over the past few years has caused the sea ice in the Antarctic Peninsula to advance two months later and retreat more than one month earlier. According to Dr. Friedlaender, the number of days when the sea ice covers the Antarctic Peninsula has decreased by about 80 over the last 50 years. Critical feeding areas for baleen whales are also overlapping with the krill fishery, and a big concern for WWF is that the industry wants to increase the total krill catch.
“WWF is working with Dr. Friedlaender and his team to put his vital new information about whales before decision makers,” Chris Johnson said.
“These tags are helping us understand not only how baleen whales forage but also the locations of their favorite feeding spots. This will allow us to work with CCAMLR and the industry to keep fishing away from these critical feeding areas,” he said.
“We hope that when CCAMLR next meets it will pass new proposals for important new marine protected areas for the Antarctic Peninsula and Weddell Sea and a proposal for East Antarctica that was rejected last year,” he said.
