As staff members from the Vancouver Aquarium gently lowered the rescued porpoise dubbed Levi from a boat into the water, Roberts and one other reached for the animal, holding it briefly between them before it quietly swam away from their arms and slipped under the surface.
Minutes later, and to everyone's relief, a dorsal fin surfaced, letting Roberts, a marine mammal rehabilitator, and the others know that Levi was OK.
The animal was found stranded and near death in the same area several months before.
"It's a huge deal to see him go back to the ocean," said Roberts, who teared up once she got back onto the boat. "It's really rewarding to be able to see it happen, and see him go back to the wild, but of course we'll miss him."
Roberts, along with other staff, spent the last five months bringing Levi back to health at the Vancouver Aquarium's marine mammal rescue centre. The cetacean was found stranded on a shoreline in March, unable to swim on its own, suffering from a severe lung infection and problems with its hearing.
Veterinarian Dr. Martin Haulena says Levi appears to have made a full recovery, which is rare because stranded cetaceans generally don't have a high chance of rehabilitation.
"These guys were never designed to be on land," he said. "They were never designed to bear their own weight, and they were never designed to be exposed to the elements like that."
Once stranded, most cetaceans start to have trouble breathing as they suffocate under their own weight, or develop skin problems or heart and kidney damage, he said.
After months of treatment, Levi was recently deemed releasable by the Department of Fisheries and Oceans. So at the crack of dawn on Tuesday, the porpoise was given a mild sedative, was placed on a stretcher and lifted onto the back of a boat.
As the vessel sped off towards Saanich Inlet, where Haulena aimed to release Levi, a team of experts tended to it, constantly monitoring its breathing and keeping it moist with wet towels.
Even though Levi is used to being out of the water and being handled by people, Haulena said the boat ride is foreign to it and could cause it anxiety. Indeed, halfway through the bumpy two-hour journey, Levi's breathing changed slightly, indicating it was getting stressed, and staff had to give the animal another dosage of the mild sedative.
But once Levi was back in the water near where it was found, and where Haulena said it should have the highest chances of survival because it should be familiar with the area, the porpoise appeared to feel right at home.
"He calmly entered the water and swam away from us, and spent a good, long amount of time under the water, not surfacing very quickly or very often," Haulena said. "He's swimming, as far as we could tell, as normally as a porpoise could swim."
Like Roberts, Haulena said Levi will be missed.
"He's such a special animal," he said. "He represents so much hard work ... and every breath he takes at the surface is like, 'Yes — there he is.'"
Levi is the first cetacean that has ever been rehabilitated and released by the rescue centre, and a satellite-linked transmitter has been attached to its dorsal fin so aquarium staff can track its movements.
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