A mother grey whale and her calf are free after the pair became stranded off the coast south of Vancouver Friday afternoon.

Few details were immediately available, but the whales could be seen as CTV News Vancouver's Chopper 9 flew over the Tsawwassen coastline at around 4:30 p.m.

The whales – which Ocean Wise confirmed were a mother and calf – seemed to be stuck off Centennial Beach by Boundary Bay. The tide was low at the time, but it appeared the whales' bodies were still partly submerged. The tide starting coming back in as crews responded.

The video initially showed the animals making small movements only. By 6 p.m., the tide was high enough that the animals where more active, but still couldn't leave the area, and by 6:15 the smaller of the two was distancing itself from the larger one, which was still moving slowly.

The pair finally appeared to have enough water to swim in at around 7:15.

Stefan Geffke lives nearby and told CTV News he was going to check the tide when he first noticed the stranded animals.

"I could hear the sound of the whales, like the blowholes, and I could kind of see them," he said.

"I could see they were struggling. It was still probably about six feet deep where they were, so they were trying to get out … When I got closer, I could see they were actually kind of stuck on the sandbar."

DFO said its marine mammal response unit was on site, adding that crews would use re-floatation equipment to try to move the whales.

"Care must be taken to ensure safety of the whales and personnel," the department said.

Geffke said one whale was about 30 feet long, and the other was between 15 and 20 feet.

"It's like a mother whale and a baby whale. That's what I'm guessing," said.

"I figured – what am I supposed to do? I have to help these poor creatures here."

That's when Geffke said he called DFO, which sent personnel from Victoria.

The Vancouver Aquarium also said it was sending a crew and a Coast Guard helicopter was also on scene.

Adult grey whales can up to 15 metres long and weigh as much as 40,000 kilograms, according to the National Oceanic and Atmospheric Administration.

Crowds were starting to form as crews set up for the operation. Officials are asking members of the public to stay at least 100 metres away.

Multiple grey have reportedly washed ashore this year during the migration between Mexico and Alaska.

With files from CTV News Vancouver's Angela Jung and The Canadian Press

DFO’s boats have been following the mother and calf and says they are now in deep water and “acting like normal grey whales.” There were some concerns at first because the animals were so disoriented from being stranded for hours. https://t.co/iSahj09LVr — Angela Jung (@AngelaJungCTV) May 11, 2019

Our @vanaqua Marine Mammal Rescue team is on site at Boundary Bay, as DFO monitors trapped mother and calf grey whales. Tide is coming in now, so the hope is they will soon be able to swim away. pic.twitter.com/a2OsPvcjRj — Ocean Wise (@OceanWise) May 11, 2019

A Boundary Bay resident noticed two grey whales thrashing their tails and appeared to be stuck in the sandbar. He called DFO and took this video. More here: https://t.co/jRb9Fn1HY1 pic.twitter.com/XOvhx4aNNo — Angela Jung (@AngelaJungCTV) May 11, 2019

The two grey whales stuck off Centennial Beach are moving more and appear to be getting ready to leave. Follow along live: https://t.co/nNhdkssVCZ pic.twitter.com/3gDjQpETQI — CTV Vancouver (@CTVVancouver) May 11, 2019

With files from CTV News Vancouver's Angela Jung