Port River 'stud muffin' among spate of dolphin deaths in Adelaide

Zoom is believed to be the Port River dolphin found dead on Wednesday. (Supplied: Marianna Boorman)

Zoom appears to be the latest dolphin found dead on the Adelaide metropolitan coastline.

His death follows a number of dolphin carcasses washing up on beaches in the area.

All carcasses will undergo necropsies to determine the cause of death.

Environmental authorities are investigating what caused the death of a popular Port River dolphin, the carcass of which was the latest among several to have been found on the Adelaide metropolitan coastline.

Warning: This story contains images that may be distressing to some readers.

A Department for Environment and Water spokesperson said park rangers were notified of a carcass, believed to be that of Zoom, found at Snowden Beach in the Adelaide Dolphin Sanctuary on Wednesday.

"Rangers did not detect any external injuries but the carcass was in a state of decomposition," they said in a statement.

Whale and Dolphin Conservation volunteer Barb Saberton said they have been monitoring Zoom, aged 30 to 35 years old, for a sunburn injury.

Zoom frequented various parts of Port River. (Supplied: Barb Saberton)

"I think the greater community is going to be grieving him for sure," she said.

The latest dolphin found dead is believed to be the "stud muffin" Zoom. (Supplied: Barb Saberton)

Ms Saberton said the dolphin, identifiable from a white mark on his left side, was frequently spotted swimming near a carrier ship in the sanctuary.

"It was nice to watch him come in on that and surfing his little heart out, because we don't get the natural waves in the Port River that you do out in the ocean," she said.

The department spokesperson said two dead dolphins had been reported to have washed up at Hallett Cove on June 5 and 6 and the remains of a third found at Henley Beach on June 10.

All four carcasses have been taken to a pathology laboratory to undergo necropsies.

A dead female common dolphin washed up at Hallet Cove beach on June 6. (Supplied: Johanna Williams)

Citizen scientists Susan Belperio and Johanna Williams came across one of the dead dolphins, which they have named Naia, and showed photos to dolphin researcher and conservationist Mike Bossley.

"He looked at the photos that we took and decided, in view of his experience, she appeared emaciated," Ms Belperio said.

Johanna Williams (left) and Susan Belperio have been documenting marine deaths since the start of the algal bloom. (ABC News)

Lisien Loan, director of conservation at the Department for Environment and Water, said the algal bloom may not hav