A 3.2 metre crocodile has been spotted at popular swimming spot Noosa Spit, with multiple sightings at the weekend.

A number of people took to social media to tell residents about the sighting.

The Department of Environment said it was taking the matter seriously and investigating the sightings.

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Fisherman James Graham and pal Kai Tapley spotted the crocodile in one of Sunshine Coast’s busiest waterways, with crocodiles rarely seen so far south in Queensland.

The Boyne River near Gladstone, some 300km to the north, is commonly considered the southern boundary of typical crocodile habitat.

Graham and Tapley appeared on Sunrise on Monday, speaking about their unexpected sighting.

“(We were) fishing and looking at the sonar ... I saw the shape come through. I had a look at it again. I said, ‘that doesn’t look right.’ I had a closer look,” Tapley said.

Graham said he knew Tapley was correct after he spotted the croc.

“The moment you see it, you know it’s a croc,” Graham said.

“So, then you go ‘that doesn’t make sense, but what else could it be? It’s not a turtle. It’s not a dolphin. It’s not a mermaid. It’s a croc’.

“So, of course, you go ‘how is that possible?’ But that’s what we saw.”

Graham explained the day started with a rumour a resident had spotted a crocodile.

However, Graham didn’t believe him.

“(I thought) in the middle of winter, as far south as Noosa, that’s just ridiculous,” Graham said.

“Maybe they let some Victorian up here again and he spotted a stick floating down the river.

“But then I thought, ‘go fishing. Get out on the water. See what’s about.

“And when Kai pointed that out on the Garmin fish finder, I knew straight away, that’s a croc!”

Tapley explained residents and tourists often went stand-up paddleboarding on the river or used kayaks.

“For it to be in that shallow water is quite scary, in a way,” he said.

Graham said he hopes the crocodile leaves the area as fishing had become suddenly “very quiet”.

“We were looking at each other going “What’s with today? There’s no fish around,’ then the crocodile kinda comes through. It sort of explained it.

“I’m keen to get back fishing again.”

Crocodile investigation underway

The Department of the Environment, Tourism, Science and Innovation confirmed an investigation is underway.

“We are aware of social media reports regarding a reported crocodile sighting today at the Noosa Spit and are investigating the matter further,” it said.

“The Boyne River near Gladstone, some 300km to the north, is commonly considered the southern boundary of typical crocodile habitat.

“Crocodile sightings should be reported by using the QWildlife app, completing a crocodile sighting report on the DETSI website, or by calling 1300 130 372. We investigate every crocodile sighting report we receive.”