nature
Cheetahs of the ocean

Pilot whales rely on the same high-risk, high-gain hunting strategy as cheetahs do

SPANISH biologists have unearthed evidence that deep-sea whales, which are known to be slow and energy saving creatures, are indeed the cheetahs of the ocean. Experts at La Laguna University say that they have observed super-fast pilot whales sprinting after their preys, which may even include giant squid sometimes.

In their study report, appearing in the Journal of Animal Ecology, the researchers say that the highly specialised hunting strategy the cetaceans use is very similar to the strategies cheetahs use.

The researchers have even successfully recorded such remarkable behaviour of the whales, hundreds of metres underwater in complete darkness.

"As far as we know, no other whale has been recorded to swim nearly as fast at depth," the BBC quoted marine biologist Natacha Aguilar Soto of La Laguna University in Tenerife as saying.

"Short-finned pilot whales seem to be the greatest burst-speed athletes of the deep-diving mammals," the researcher added.

During the study, the researchers attached a tag to 23 short-finned pilot whales (Globicephala macrorhynchus) living off the coast of the Canary Islands, with the help of which they could record the speed, depth and direction of the whales’ dives, as well as the sounds made and heard by the whales.

While scientists previously thought that the whales only hunt at night, the tags demonstrated that the whales also hunt during the day. The tags also revealed that when the whales surged after their prey, they reached the speeds of 32 km per hour, and might keep up the sprint for 200m (650ft), before either catching the prey or giving up the chase.

Aguilar Soto said the new findings contrasted the existing perceptions of how deep-sea creatures behave, such as the belief that deep-diving whales moved relatively slowly due to the need to conserve oxygen while holding their breath.

"It was completely unexpected that short-finned pilot whales sprint at depth with limited oxygen reserves. Cheetahs, for example, more than double their breathing rate during chases," Aguilar Soto said.

The researchers said pilot whales rely on the same high-risk, high-gain hunting strategy as cheetahs do. According to them, the whales do it while still holding their breath. Aguilar Soto said such behaviour of whales indicates that they are spotted lazing on the surface perhaps due to the fact that they might be actually recovering from the exertion of the hunt. — ANI

HOME