A dolphin injured in a suspected propeller strike in Western Australia’s south west has raised concerns about the animals’ interactions with humans.

Warning: This story contains images of injured animals.

The Dolphin Discovery Centre said it had received reports this week about a cut to the back and tail of a dolphin in Bunbury’s Koombana Bay, some 160 kilometres south of Perth.

The wildlife conservation group says it had the identified the injured dolphin as Fence, whose calf Coupe was also injured late last year.

Spokesperson Emily Ehlers said the centre had seen an increase in the number of injured dolphins.

Two dolphins stick their snouts and dorsal fins above the water as they swim in the ocean.

Dolphins are known to frequent the waters at Koombana Bay, in Bunbury. (Supplied: Aquatic Megafauna Research Unit/ Valeria Senigaglia — taken with permit)

“Last year we recorded five and this year we’ve recorded three, whereas previous years we’d only seen one or maybe even two,” she said.

“So to have five and then to already have three in 2026 is really concerning.”

Ms Ehlers said it was not clear what had injured Fence, but human activity was likely involved.

“Just from the way the cut is so clean and flat, we think that it’s probably a propeller strike,” she said.

“It’s concerning on quite a few levels, because on an individual level the dolphin calves are already vulnerable, that’s increased when there’s a vulnerable mother as well.”

‘Pretty horrific’

Rodney Petersen, director of citizen-science association Geographe Marine Research, took the footage of the injured dolphin.

“I got a message from a member of the public who was out on a boat and waited until I could get there with a drone,” he said.

“The injury was pretty horrific.” 

Two dolphins with cuts on their back swim side by side, as seen from above.

Fence (right) is the mother of Coupe, who is also recovering from an injury. (Supplied: Rodney Petersen)

He immediately passed the footage on to wildlife authorities.

Mr Petersen said the incident is the latest in a series of injuries to dolphins in the past few years. 

The dolphin was likely injured by a sharp object, he added.

“This was probably one of the worst ones,” Mr Petersen said. 

“There’s a lot more boats out here, a lot more jetskis … you’re in a dolphin area and you need to slow down and have a look around.” 

A Department of Biodiversity Conservation and Attraction (DBCA) spokesperson said the authority was aware of the injuries.

“There have been a few instances of dolphins presenting with different lacerations in the area over the summer,” they said.

“DBCA is monitoring reports and the health of these dolphins.”

A large sculprute outside a bright-coloured building near the ocean.

The Dolphin Discovery Centre says it has recorded an increase in injured dolphins. (ABC South West WA: Jacqueline Lynch)

Increase in begging behaviour

Bunbury, WA’s second biggest city, is home to some 200 dolphins. The Dolphin Discovery Centre, where visitors get to see the animals in their natural habitat, is a popular tourist attraction.

More dolphins, however, are approaching boats and humans for food, and this “begging behaviour” is putting them at risk, Ms Ehlers said.

The injured dolphins, Fence and Coupe, had approached members of the public and the centre’s own research vessel, she said. 

Ms Ehlers hopes Fence’s injury will heal. 

“We think that flap of skin will necrotise and will hopefully drop off,” she said.

“Her body cavity hasn’t been affected, which is a really good thing.” 

Injured or sick wildlife can be reported to the Wildcare Helpline on (08) 9474 9055