Sea lion with nylon rope around its neck rescued by Vancouver Aquarium

A Steller sea lion that had a thick piece of braided plastic cutting deeply into its neck has been saved by the Vancouver Aquarium's Marine Mammal Rescue Centre.

Rescued female was full grown and estimated to weigh about 260 kilograms

A sea lion leaps out of the water during a demonstration at the Vancouver Aquarium. Aquarium staff with help from Fisheries and Oceans Canada rescued a sea lion (not pictured) from nylon rope Tuesday. (The Canadian Press)

A Steller sea lion that had a thick piece of braided plastic cutting deeply into its neck has been saved by the Vancouver Aquarium's Marine Mammal Rescue Centre.

The aquarium says the team that saved the female sea lion on Saturday also tried to help a younger animal entangled in a plastic packing strap, but the animal was able to bite out a sedative-carrying dart and bolted into the ocean.

The rescued female was full grown and estimated to weigh about 260 kilograms.

In Canada, the aquarium says Steller sea lions are a species of special concern, and some populations, in parts of Alaska, are endangered.

They are the biggest of the sea lions.

The rescue was done with the help of vessels from Fisheries and Oceans Canada.

The aquarium says the nylon rope will now be analyzed to determine what kind of plastic it's made from in the hope the public, industry and government will be encouraged to reduce the use.

Dr. Martin Haulena, the aquarium's head veterinarian, said the rope was cutting "quite deeply" into the rescued seal lion and eventually she would have died.

"The problem of plastic pollution in our oceans is becoming a crisis, and it's one that we all need to take more seriously in our daily lives," Haulena said in a news release on Tuesday.

"From debris that causes entanglement of marine mammals like these, to smaller plastics that get ingested by fish and animals at the bottom of the food chain, our single-use plastic waste is having a huge impact."