Tailed whales: Scientists track unique humpback whale ‘fingerprint’

Different populations of humpback whales live in oceans around the world.

Onboard the ARC Simon Bolivar in Antarctica:

In Antarctica, a scientist waits patiently for two playful humpback whales to poke their tails out of the icy waters so she can take a photographic “fingerprint” of unique colors and patterns, allowing researchers to identify the species of individuals.

Andrea Bonilla, a Colombian scientist at Cornell University in the United States, has been working with a research team since 2014 to classify humpback whales through visual analysis of their tails, or tail fins.

“What we are doing is tracing everyone’s history,” Bonilla told AFP aboard the ARC Simon Bolivar during a scientific expedition by the Colombian navy.

Over the years, the team has identified 70 whales and hopes to see some of them again to record any physical changes that could provide clues to their migration patterns, population size, health and sexual maturity.

On the tail, “each whale has a unique color and pattern, like a fingerprint, so what we have to do is look at their different marks, their different scars” to identify individuals, Bonilla said.

Global humpback whale populations have recovered after being decimated by commercial whaling, but these ocean giants remain threatened by ship attacks, illegal fishing, pollution and underwater noise.

According to the International Union for Conservation of Nature, there are approximately 84,000 adult individuals in the world today.

The importance of tail identification was underscored by a study published last month in the journal Royal Society Open Science that showed North Pacific humpback whale populations have plummeted by 20% in less than a decade.

Scientists, who tracked some 33,000 whales through photos of their tail fins, found a dramatic decline in whale numbers that they speculated was caused by starvation caused by ocean heat waves.

“Gather energy”

Photo identification is common in the study of marine mammals, although fluke identification is most often used with humpback whales because of their unique markings, and their habit of lifting their tails out of the water when diving.

Different populations of humpback whales live in oceans around the world, making massive migrations from warm breeding grounds to feeding grounds in polar waters.

“They take advantage of the abundance of food biomass here (in Antarctica) and over the course of several months they just accumulate energy,” Bonilla said.

Scientists used photographs to create a detailed replica of the tail of the giant marine mammal, which is 18 meters (59 feet) long and weighs about 40 tons.

On the computer, she zooms in on details of the fluke, which could reveal attacks by other animals, “whether there’s some type of skin disease” or information about their diet.

The inventory allows scientists to track the movements of specific whales, which is crucial for conservation initiatives.

“If whales always come to the same areas to breed, it’s important to protect those areas. If they cease to exist or are disturbed, that whale will have nowhere to go,” Bonilla warned.

(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)