In a conversation  BBC, Jeremy Goldbogen, Assistant Professor of Biology, Hopkins Marine Station of Stanford University, answered questions on the diet of the largest living mammal, the blue whale, from his research, Nature World report reports.

The primary diet of the blue whales consists of krill, the tiny oceanic creatures that usually measure upto 1-2 centimetres. However, in comparison to the small size of their primary diet, the blue whale can grow to be more than 100 ft. long and weigh over 180 tons.

The blue whale can consume as many as 40 million krill per day.

Scientists have pondered over questions on whales such as what is life like with the extreme body size? How did whales get so big and how do they manage to support such bodies and their large energy demands?

A new study, published in Science Advances, focuses on the feeding pattern of the blue whales by providing examples of the blue whale foraging specializations that support the animals' huge size.

The study was conducted by researchers from NOAA Fisheries, Oregon State University and Stanford University.

"For blue whales, one of our main questions has been, how do they eat efficiently to support that massive body size," said Elliot Hazen, a research ecologist with NOAA Fisheries' Southwest Fisheries Science Center and lead author of the research.

"Now we know that optimizing their feeding behavior is another specialization that makes the most of the food available."

The researchers say that research on blue whale feeding will help determine how best to protect the species. The blue whale is listed as endangered by the International Union for Conservation of Nature.