Blue whales swim to the surface to feed krill, and it does not help them save energy, according to a new study that contained huge drone recordings of mammals.
& # 39; Oregon State University experts found that nutrition on the surface of & # 39; Ocean plays an important role in hunting for food among New Zealand's blue whales.
Blue whales are the largest mammals on earth and must carefully balance the cost of energy obtained from food with the cost of energy used to obtain food.
Researchers said that marine mammals feed for krill in areas where they are tightly packed and found near the surface of the water to cut their divide.
The Oregon team found that the blue whales are doing this to save the energy costs of feeding such as diving, holding their breath or opening their mouths.
Adding to the challenge, their prowess are small and so they need large volumes of & # 39; find and eat small crustaceans to make any energetic progress.
Study author Dr Leigh Torres, an assistant professor at & # 39; Oregon State University, said: & # 39; People thinking about whales need to dive deep to get to the densest prey patches.
& # 39; But if they can find their prey in shallow waters, it is actually more profitable to feed near the surface, & # 39; said Torres.
Blue whales swim to the surface to feed krill, and it does not help them save energy, according to a new study that involved huge drone recordings of mammals
& # 39; In this population of whales in New Zealand, they fought more in areas where their prey was close and shallow.
& # 39; Their dikes were relatively short, and they fought more on the surface, requiring less energy. & # 39;
Tags posted on blue whales record where they travel and their diving patterns – and give researchers most of their knowledge about the marine creatures.
Until now, surface feeding was not so well understood – partly because it is more difficult to analyze tag data and quantify the size of prey patches on the surface of the water.
During a field research trip to study blue whales off the coast of New Zealand, Dr Torres and her team observed overfishing of their boat.
They were also able to capture drone recordings from the food used in & # 39; the study.
Blue whales are the largest mammals on earth and grow up to a maximum of 98 feet
Blue whales grow to a whopping 98 feet and weigh up to 190 tons.
Not only are they the largest mammals on Earth, but they are the second largest animal to have ever existed.
The marine mammal has a long and slender body and is part of the sequence of bales.
Blue whales are listed as endangered in terms of conservation status due to hunting for whaling.
They are found in & # 39; eastern northern Pacific, central northern Pacific, northern Atlantic, and Antarctic oceans, as well as in & # 39; a neighborhood of New Zealand, the northern Indian Ocean and Chile.
They can swim at about 4.6 miles per hour, but average about 1.68 miles per hour, but if they hunt, they can reach up to 30 miles per hour.
The researchers noted that the density of krill patches was closer to the surface of the water and the likely reason the whales were picking those areas to feed.
Findings showed that New Zealand blue whales were relatively short dive times in general of about 2.5 minutes – compared to other blue whale populations that could see diving times of more than 10 minutes.
The dive time of New Zealand blue whales slowed down even more – to less than two minutes – when surface feeding was detected by drone recordings.
The video shows the mammal feeding process, including decision making about whether or not to place krill at the surface of the ocean or not.
It also gave researchers another source of data to describe surface feeding behavior in marine mammals.
Co-author Dawn Barlow, a doctoral student in Dr. Torres's lab, said the recordings made a hole in his & # 39; e scientists follow about understanding surfaces.
The footage showed investigators how the whale used his right eye to direct the prey before he went for the kill.
They were also able to quantify the distance from the whale to the prey and measure how wide the whale opened its mouth to graze.
Blue whales are the largest mammals on earth and must carefully balance the cost of energy they receive from food with the cost of energy used in obtaining food.
The video also showed the decision of & # 39; the whale to & # 39; turning one side to the other to better capture the krill.
& # 39; The video shows us some really cool kinematics and coordination of body movement described by the whale that we couldn't see before, & # 39; said Torres.
& # 39; The recordings also showed us the proai response in new way. We can see when the krill starts to flee when the whale arrives, which is really amazing.
& # 39; At the fastest speed and acceleration of & # 39; a whale starts the krill just eight tenths of a second before the whale strikes the & # 39; krill patch. & # 39;
Although the researchers had footage of surface of only one whale, the footage included four encounters between those whales and surface prey patches.
It provides insight into decision making by the whale in response to & # 39; size and orientation of & # 39; a proai patches.
& # 39; These recordings highlight the value of using drones for studying and observing whales, & # 39; said Torres.
& # 39; Drone recordings can be a good addition to data collected from tags for studying whaling surface behavior. & # 39;
Findings were published in the journal Peer.