Whales are known for their humongous size, known to be the largest. Scientists have come to know about its feeding cycle to gain such mass after years of research. According to a study, blue whales, the largest animal on Earth, have a filter-feeding strategy. It is determined that a single mouthful of food contains 457,000 calories which are 240 times higher than the energy burned when grabbing that mouthful.
Blue and other whale species eat by taking a mouthful of water and then filtering in their meals, often tiny crustaceans called krill, using plates of baleen made of keratin, a protein found in hair, fingernails and feathers. Jeremy Goldbogen of Scripps Institution of Oceanography calculated the efficiency of this kind of feeding through research.
Their math supports the long-standing assumption of Baleen whales being more efficient feeders than their toothed smaller relatives who hunt individual prey. Study researcher Robert Shadwick, who studies animal biomechanics at the University of British Columbia, stated that Baleen whales’ efficiency is unprecedented in the animal world. He said, “When they take a gulp of water, they are filling their mouths with the amount of water equal to their own body mass, so there is nothing that comes close to doing that.”
As per various research, it was found that whales eat an enormous amount in a single mouthful, but the energy burnt during this process is taxing. As they dive in for the mouthful, they lunge into a school of krill and their mouths open to 80 degrees and inflate like a parachute as water gushes in, which in turn creates a drag and slows down the whales. Six lungs compensate for this during a dive.
Researchers recorded around 200 dives of whales from 2002 to 2007 to calculate the amount of energy used. It was found through various research that a whale uses about 8,071 kilojoules (1,900 Calories) on a single lunge. The researchers also found the amount of energy the animals captured in one mouthful. The answer is up to 1,912,680 kilojoules (about 457,000 Calories).
Shadwick said, “They are doing something that is energetically very expensive, but they are getting an enormous payoff.”