A pod of around 20 orcas were spotted swimming off Cape Naturaliste at Sugarloaf Rock on Sunday afternoon.
Dunsborough wildlife photographer Ian Wiese captured these images around 3pm and said he had never seen an orca in the area before.
"I saw them about two kilometres west of Cape Naturaliste and they slowly moved about three kilometres south and further out," he said.
Curtin University PHD candidate Rebecca Wellard is currently running Project Orca off Bremer Bay in the WA's Great Southern.
Ms Wellard said she has been studying killer whales off WA's coastline since 2014 and collected citizen science reports and sighting of orcas.
She had a look at their database of sightings off Cape Naturalise, they had recorded a sighting in 2012 off Busselton and since then there had only been two more sightings both in 2017.
"We had a high number of sightings off western Rottnest Island, Lancelin and Two Rocks but that could be because there were more people on the water in those places.
"I tried to match Ian's images to the animals we have in our catalogue of all the killer whales that have been reported in WA.
"We look at the dorsal fin, eye patch and saddle patch and there were no matches, we do not know where they are from.
"I study the killer whales off Bremer Bay every year and they are highly marked, but there are definitely no matches.
"I compared them to all killer whales in Busselton and previously Cape Naturaliste, Bremer Bay, Rottnest and Ningaloo and they are not the same."
Ms Wellard said while there are quite a few sightings off WA they did not know how many killer whales there were.
"They are highly mobile animals so it can make it really hard to study them, but the good thing is they are unique in that they have these characteristics in their dorsal fin and eye patch, which are as unique as a human fingerprint.
"If we get good quality images it really helps us put another piece to the puzzle to see if we can match them."
Ms Wellard said when they were seen off Cape Naturaliste in 2017 the orcas were attacking a humpback whale calf.
"They are know to predate on humpback calves in the north-west which is what they are doing now in Ningaloo," she said.
"We have had them attacking humpback calves off Lancelin and Two Rocks, but they feed off other things as well.
"There is a lot of other prey they could potentially be feeding on off the coast."
Ms Wellard said if anyone had an images or had sighted orcas out on the water to send them into Project Orca by emailing project.orca.australia@gmail.com.
"Any little bit of information helps us get a better understanding, and if they were there on Sunday they might still be around," she said.
