Rare photos capture ‘spectacular’ behavior of ocean giants in Australia. See them race

Despite being the largest animal on the planet, blue whales maintain a life of secrecy, spending their days in the deep, open ocean.

The opportunity to see a blue whale comes once-in-a-lifetime for most, but for Peter Gill, blue whales are his life.

Gill runs Blue Whale Study, a nonprofit organization studying blue whales and their feeding habitat off the southern coast of Australia.

He shares photos of his days in the “office” on social media, including sightings of oceanic birds, dolphins and blue whales’ smaller cousin, the humpback whale.

In March, despite two decades on the sea, Gill saw a blue whale behavior that left him shocked.

“As a researcher, every so often you are blessed with a truly awesome experience watching animals,” he wrote in a March 29 Facebook post. “Last week during an aerial survey, we found three blue whales engaged in ‘racing behavior,’ in which a presumed adult female is pursued at high speed by two competing males, prospective mates.”

Gill said he has only seen the behavior once before while blue whales were in Australian waters during upwelling, when cold, nutrient-rich water rises toward the surface of the ocean, in 2003.

“The frequent changes of pace and direction were clearly dictated by the female, and males did their best to stay close to her, while trying to outpace and physically displace each other,” Gill said.

The whales pair up before they migrate away from the Australian feeding grounds up toward Indonesia, Gill told ABC, but said it is more like “full on combat” than some kind of mating dance.

“They’re shouldering each other aside and hitting each other with their tails a bit,” Gill told the outlet. “The female’s just out in front setting the pace … she slows down when she wants to have a rest and the two boys both slow down too and trail behind her, and then she’ll power off again and off they go. Presumably she’s going, ‘OK, boys — who’s it going to be?’”

Blue whales can reach 100 feet long and weigh up to 330,000 pounds, according to the National Oceanic and Atmospheric Administration.

The ocean giants live in all oceans except the Arctic, NOAA says, and migrate seasonally between summers in cold waters and winters near the equator.

Gill said he and his team circled above the whales for about 15 minutes before leaving them to continue their racing.

“It was a spectacular display of massive power and grace, one of the great sights in nature,” he said.

Blue Whale Study is based in Narrawong on the southeastern coast of Australia, about a 200-mile drive west of Melbourne.

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