The two southern right whale dolphin carcasses were found in separate sightings at Port Fairy's East Beach in early December, and again in early January.

In the first incident, following consultation with land managers and traditional owners, the deceased animal was removed from the beach by Victoria's Department of Environment, Land, Water and Planning (DELWP) wildlife officers.

The second sighting was reported to DELWP on January 10.

DELWP arranged for the site to be inspected that day but no evidence of the dolphin was found.

The department confirmed the species based on images posted on social media and determined that the specimen likely washed up on the beach a couple of days before it was reported.

The southern right whale dolphin is a small and slender species of mammal found in cool waters of the Southern Hemisphere, and their appearances in waters off Victoria are extremely rare.

DELWP natural environment programs officer Mandy Watson said the dolphin was the first of its kind to ever be recorded in Victoria.

She said it was important for members of the public to call the Whale and Dolphin Emergency Hotline when there is a sighting, as ocean tides often wash mammals back out to sea.

"In the event of a whale or dolphin stranding, DELWP will assess the emergency situation to determine the appropriate response," Ms Watson said.

"If a whale or dolphin is dead when DELWP officers arrive, DELWP can gather important scientific information about the species and cause of death, before working with land managers and traditional owners to determine the most appropriate method of disposal."

Sightings of injured or dead whales or dolphins should be reported to the Whale and Dolphin Emergency Hotline on 1300 136 017.

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