Australian sea lion killed after being struck by a car on one of Adelaide’s busiest roads

Commuters on Adelaide’s busy north-south motorway were in disbelief on Monday morning at the rare sight of a sea lion.

That disbelief was sadly short-lived, however, after a driver failed to see the animal. It was killed when she hit it with her car at Dry Creek in Adelaide’s north.

The male sea lion was spotted the day before in the mangroves around the area but wasn’t moved as he was thought not to be in danger, and too difficult to move by environmental authorities.

The driver who hit the sea lion about 6am on Monday, Hayley Steele, told The Advertiser she was shaken up by what she called a “gruesome” incident that left blood all over the side of her car.

WATCH ABOVE: Authorities unsure how the male sea lion ended up the expressway.

She said the colour of the animal blended in with the road and while she noticed traffic merging out of a lane it was unclear why until it was too late.

Another passer-by, Matt Cuming, said the sheer size of the sea lion was impressive.

“It would have been a big shock that’s for sure,” he told 7NEWS.

“We couldn’t believe it, I didn’t expect to see a seal hit by a car on the road, especially out there anyway.”

Ivan Nagelkerken, a marine biologist from Adelaide University, said it wasn’t the animal’s fault.

“It’s not their fault, because we’ve actually invaded their territory,” he told 7NEWS.

“Now that we’ve got a lot of coastal development, it’s much easier for them to accidentally move onto the road.”