Baleen whales swallow much more food than was initially thought according to a recent study of filter-feeding whales that shows the importance of their eating habits in nutrient recycling in the ocean. The study shows that the different Baleen whales such as blue, fin, minke, and humpback whales consume at an average of around three times more each year than previous estimates. For instance, a blue whale in the eastern North Pacific can eat between 10 and 20 tons of food each day.
”That amount of food is somewhere in the range of 20 to 50 million calories. That is about 70- to 80-thousand Big Macs. Probably decades of our eating is one day for them. So it's pretty remarkable," said Matthew Savoca, a researcher at Stanford University and the lead author of the new study.
He added that the only data he could find about how much whales eat "didn't actually come from living, breathing whales in the wild." Researchers had only made extrapolations from the caloric needs of smaller animals or from the stomach contents of hunted whales.
To get more accurate estimates, an underwater device was used that can measure the size and density of swarms of shrimp like krill. Krill are the main diet of whales, and the device can measure their number by sending out pulses of sound that bounce off the krill swarms and return. The gathered data of Savoca and colleagues came from more than 300 tagged whales.
Image: Duke University Marine Robotics and Remote Sensing Lab
Whale tagged by the research team
Image: Ari Friedlaender