In the dead of night, a lion mauled in a territorial brawl and limping thanks to a poacher’s trap that years earlier ripped off part of a leg, entered Kazinga Channel in Uganda and swam for more than a kilometre through waters defended by hippos and infested by crocodiles.

A thermal drone camera operated by a Queensland biologist’s research team hovered above. The researchers who captured the extraordinary crossing by the lion, named Jacob, alongside his brother, Tibu, have now reported it was the longest-ever swim by lions on record, smashing the previous distance of 300 metres.

The event not only contributes to the epic legacy of Jacob, a lion whom Griffith University’s Dr Alexander Braczkowski has studied for years; it’s also a key illustration of the extreme lengths the world’s remaining wild creatures are taking to survive.

“What you’re seeing here is a bigger symptom of the human-wildlife interface,” Braczkowski said.

“This is just another example of how animals, and specifically lions, are having to take riskier decisions to try to fulfil the basic tasks of just being alive, to feed and to find mates.”

Braczkowski’s team was tracking Jacob and Tibu through Queen Elizabeth National Park in January when the brothers were set upon by another pair of males. Two days later, they were attacked again and badly wounded by rivals.

The number of lions in the park has halved in five years. Competition for breeding rights is vicious. Driven to seek out females elsewhere and spooked from using a bridge further up the channel because it is frequented by humans, the brothers took the ultimate risk.

The pair stalked the shallows for an hour before attempting to cross. They made it 15 metres before scrambling back to shore.