For decades researchers believed that blue whales mindlessly engulfed every bit of prey they could found in the ocean. But a recent study revealed that the sea behemoths carefully plan their meals beforehand to preserve energy and maintain a constant weight.
Blue whales usually feed on tiny shrimp-like animals known as krill. But density of krill patches play a huge role in whether the large mammals would start to feed or postpone meal for a later time.
Researchers from two U.S. universities and National Oceanic and Atmospheric Administration’s Fisheries learned that the less dense krill patches were the less likely blue whales would start feeding on them. Researchers explained that the huge animals thus saved oxygen and energy and prevented weight loss.
Elliott Hazen, lead author of the study and NOAA researchers, said that blue whales enter an eating frenzy when krill populations are dense, but would rather fast when prey is scarce. The team explained that whales consumed a lot of energy and oxygen when eating so they carefully need to plan when it is the best moment to feed to maintain their legendary size.
An adult blue whale can outweigh 25 chubby elephants and grow as large as a basketball field. When they forage, they engulf as much sea water as their body size, and immediately throw it out to filter the krill in it. This consumes a lot of energy, so the prey needs to worth it.
“The whales are much more actively assessing their environment and taking advantage of prey in ways that were unknown before,”
noted Ari Friedlaender of Oregon State University.
Unlike what many myths tell, blue whales cannot swallow a whole boat and crew because of the dense baleen plates in their mouths that allow only tiny prey to enter. These plates are made of the same material our fingernails are made – keratin.
When they start to feed, they increase speed, open their mouths and engulf monstrous amounts of prey-lade water. Throat muscles distend the throat to allow the water to come in, but quickly contract to push water out and retain krill which gets sieved by the baleen plates.
A single blue whale can consume up to four tons of krill and other small sea creatures every day. Because of reckless hunting and dwindling food sources blue whales are now listed as ‘endangered.’ NOAA estimates that there are only 10,000 specimens left worldwide.
Image Source: Wikipedia