A half-tonne sea lion was rescued off the coast of Vancouver Island last week after being entangled in plastic garbage that dug inches into its neck.

The Stellar sea lion was rescued by a combined team of Vancouver Aquarium Marine Mammal Rescue staff, officers from Fisheries and Oceans Canada (DFO) and a veterinarian from the SeaDoc society at Race Rocks Ecological Reserve near Sooke.

When the team first arrived at Race Rocks in a DFO boat, they spotted the 500-kilogram sea lion on a rocky outcropping with a "plastic packing band" wrapped around its neck. Even from a distance, the marine mammal rescue team says, "the depth and severity of the wound indicated that the plastic had been there for some time."

The team then decided to sedate the sea lion using an air-powered tranquilizer dart to make the disentangling process easier. However, strong currents and rough terrain made landing the shot difficult in the choppy waters of the reserve.

"It took several hours of jockeying positions, on land and from the water, before Haulena [head veterinarian at the Vancouver Aquarium] was able to successfully dart the sea lion," said the mammal rescue team in a news release.

In between dart shots, rescuers say they had to also pause for a number of Southern resident killer whales as they passed through the area.

Once the animal was immobilized, the team lifted it from the water and removed the plastic band from around its neck, which rescuers say dug itself some two inches deep into the animal. Meanwhile, the team also tagged the sea lion's flippers so that if future reports about it are made, it can be located quickly.

According to the Marine Mammal Rescue Centre, the province has documented hundreds of reports of sea lions being entangled by plastic products over the past several years.

"Not only are these plastic items uncomfortable for the marine mammals but the already massive sea lions continue to grow, while the plastic around them does not," said Lindsaye Akhurst, the centre's manager.

"Such entanglements can result in death."

Anyone who spots a sea lion or any marine mammal in distress is asked to keep people and pets away from the animal and call the DFO hotline at 1-800-465-4336 or the Marine Mammal Rescue Centre at 604-258-SEAL (7325).

Marine mammal incidents and sightings can also be reported online here.