Visitors to Castlecliff Beach were excited to see a pod of "20 to 30" orca whales on Sunday afternoon - and people have been lining up in the hope of spotting them again.
Suzanne Perrin, who has lived in Castlecliff since 1977, said she thought she was hallucinating when she saw at least 20 orca swimming around the river mouth at North Mole.
Perrin was at the beach with friend Raewyn Udy around 2pm on Sunday when she noticed movement in the rolling waves.
"There must have been 20 to 30 of them, it was incredible."
Perrin said they were about 50-100 metres past the end of the North Mole. She attempted to take photos but, geared with a new camera and the murky conditions, wasn't able to get a clean shot.
"They weren't coming out. The water was quite brown and was very turbulent. There must have been fish underneath."
A former environment teacher at Aranui School, Perrin couldn't believe what she was seeing.
"He was so big he couldn't come close to shore. I thought he wasn't even an orca, he's so big. I was watching whales from sea level practically. Where else in the world can you do that?"
Perrin said there were five others at the river mouth at the time.
Around 9am on Monday, there were reports of another sighting.
Local surfer Rhys John-Carr went down to the beach after seeing on Facebook that orcas had been spotted; however, he didn't see them.
He said it was pretty common for this time of year.
"Yeah, many of them. I've surfed up by Taranaki and had them swim underneath me. So there have been a few sights.
"It's a pretty choice thing to happen here."
Department of Conservation - Whanganui supervisor recreation/historic Jim Campbell said there have been regular sightings of orcas over the last five years.
He said they were known to come into tidal waters and are often known to feed on stingrays close to shore.