Fast-acting rangers on Kangaroo Island are being praised for their efforts removing a massive piece of marine debris that washed up in an important sea lion sanctuary.

The National Parks and Wildlife Service staff sprang into action to remove a large length of drift rope and netting, estimated to be up to two kilometres long, which washed up on the main beach of Seal Bay Conservation Park.

The rangers acted quickly to secure the debris before strong tides washed it away.

It is the largest piece of debris to have washed up on the shores of the park.

The line could have come from as far away as South America.

According to environment group Sea Shepherd the biggest single source of plastic in the world’s oceans is accidentally lost or discarded fishing material, including nets, ropes, long-lines, crates and baskets.

It is estimated that about 46% of the Great Pacific Garbage Patch is made up of these types of materials.

Fishing nets lost or discarded at sea are known as ghost nets and can indiscriminately kill countless marine life and birds as they move around the oceans.

The Seal Bay removal operation comes amid a bumper start to the breeding season within the Australian sea lion sanctuary with about 200 pups born so far this winter.

Timely start for Kangaroo Island Sea Lion Breeding Season