Lions’ record-breaking swim across channel captured by drone camera

A pair of lion brothers have made the longest swim ever recorded for their species – about 1.5 kilometres across hippo and crocodile-infested waters.

The massive swim – equivalent to the aquatic leg of an Olympic triathlon – was the pair’s fourth attempt to cross the Kazinga Channel in Queen Elizabeth National Park, Uganda, and was recorded by a drone-mounted thermal camera at night.

The lions had to abort earlier attempts after encountering large animals, most likely hippos or Nile crocodiles, which are also visible in the footage.

Making the effort even more extraordinary, one of the lions, named Jacob, has only three legs.

Jacob has had an extremely challenging life, says Alexander Braczkowski at Griffith University in Australia: he has been gored by a buffalo, his family was poisoned for the lion body-part trade, he was caught in a poacher’s snare and he eventually lost his leg after it was stuck in a poacher’s steel trap.

Capturing the swim on film was unexpected because Braczkowski and his colleagues were actually monitoring the pair of lions to determine whether Jacob’s brother, Tibu, was supporting his sibling with the provision of food.

“The brotherly bonds of lions go way beyond the limitations of an injury like a missing leg,” says Braczkowski.

The researchers think the brothers probably crossed the channel to reach lionesses they could hear calling from 2 kilometres away. The linear distance of the crossing was 1.1 kilometres, but they estimate the lions swam closer to 1.5 kilometres, accounting for changes in direction.

“It’s kind of amazing when you look at individual capability and bravery in different species when it comes to passing on their genes,” says Braczkowski. “A human would never swim across that channel in the middle of the night, but a lion – even a three-legged one who has had almost everything taken from him – will just jump in.”

Braczkowski says Queen Elizabeth National Park’s lions are under immense pressure because 60,000 people also live within its limits, herding cattle, poaching wildlife and sometimes growing crops.

“Male lions are spending a lot of their time searching for new females because, in the past five years, the population of lions in the park has fallen by nearly half, from 72 to 39,” he says.

Females have been hit harder because they tend to gather in bigger groups, so if people set a poisoned carcass, there is a greater risk of multiple deaths, he adds.

“The ratio in the park is now two males for every female, and it should be two females for every male in a healthy population.”

Team member Duan Biggs at Northern Arizona University says a long-term solution will need to be found in the park that protects both humans and lions.

“A three-legged lion caught in a poacher’s trap swimming across croc-infested waters to find females is a symbol of a conservation landscape that is struggling,” he says.