A stranded dolphin has been safely returned to deeper waters after a dramatic rescue mission.

The adult male bottlenose dolphin was spotted trapped in a shallow section off Marshalls Creek at Brunswick Heads in NSW, sparking concerns when it failed to return to deeper water even after two high tides.

WATCH THE VIDEO ABOVE: Brunswick Heads Dolphin Rescue

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Authorities said it had been stranded for more than 30 hours when it was seen struggling on a sandbank late Friday, prompting an urgent rescue at low tide on Saturday.

Teams from Sea World Foundation, New South Wales National Parks and Wildlife, ORRCA, Dolphin Research Australia, and the Tweed Byron Local Aboriginal Land Council came together to carry out the complex operation.

Sea World Foundation’s Head of Marine Sciences Wayne Phillips said the group used a “human chain” to help secure the animal.

“A great rescue down here in Brunswick of a little dolphin that was stuck up one of the estuaries just near the main river,” Phillips said.

“It had been found here for the last 30 to 36 hours, and we were a bit concerned about how it was behaving.”

Rescuers managed to guide the dolphin into shallow water before it was secured and assessed by Sea World’s veterinary team.

“We had to put the animal in the back of our van, drive it down to as far as the road would take us, and then carry it for about 500 metres to where the entrance of the Brunswick River was, where we could then successfully release the animal,” Phillips explained.

“Once we saw the animal swim towards the bar, everyone was elated, such a great feeling to have a successful rescue.”

Sea World Foundation’s Head Veterinarian Dr Claire Madden led the medical assessment on-site.

“We got a call less than 24 hours ago that there was a dolphin in the creek behind me,” Madden said.

“A member of the public actually had to push it back into the water meaning it had stranded.

“That raised concern something might be wrong.”

A full health check was done in the field, including blood tests, an ultrasound, and a heart scan.

“I was very pleased to report that this individual was a candidate for immediate release,” she said.

“To see it swim off so strongly, phenomenal feeling.

“That’s what we’re all about — getting these animals back out into the ocean.”

Phillips praised the teamwork behind the successful outcome.

“Really collaborative effort… to all come together and work hard on this project has been amazing,” he said.

“It’s been a really busy start to the winter season.

“We’ve had several dolphin strandings and a couple of whale disentanglements already, so we’re looking at a big year ahead.”