Fisheries officers Jonathan Hynes, left, and Dwayne Muise try to help a beached pilot whale back to the sea near Maitland, N.S. (Courtesy Department of Fisheries and Oceans)

Fisheries officers and volunteers on Thursday rescued a pilot whale that had washed up on a Nova Scotia beach, while efforts continued to save several more.

The rescue effort began Tuesday when the Department of Fisheries and Oceans got a call that there was a stranded whale in Port Maitland, near Yarmouth.

Other calls followed, with reports of up to 12 whales stranded in the area and a few kilometres north up to Bartletts Beach.

On Thursday afternoon, DFO staff and volunteers managed to move one of the two-to-three-tonne cetaceans back into the water. They first dug a big trench in the beach and next moved the whale into the trench using a tarp and pontoons. Then it was a matter of pushing the whale out through the trench into the ocean.

Andrew Reid of the Halifax-based Marine Animal Response Society said the whale was helped to reacclimatize to the water with a pair of inflatable pontoons to keep it afloat.

"We were out in the water for probably about an hour while it regained its strength. We deflated the pontoons and it initially swam toward the shore, which was a little bit concerning, but gradually turned back out to sea and swam out."

Howard Blinn, supervisor of DFO's Meteghan office, said the beachings are unusual.

"I've been with Department of Fisheries for 20 years and I've responded to quite a few dead whales, but never to live pilot whales," Blinn said.

DFO officers from around the area have been called in. In addition to Thursday's rescue, they've helped a number of the whales back to sea over the last two days, but at least four have died.

Adult pilot whales weigh between two and three tonnes each. They are social and often found in large groups.

Blinn said he doesn't know why the pilot whales have beached themselves. But Reid said he suspects they may have become disoriented.