Fisheries Department officers training for marine mammal rescues in the waters off Nanaimo, B.C., found themselves doing the real thing earlier this week. 

The department says in a statement that an entangled humpback whale was spotted by a whale watching company on Wednesday in that area of the Georgia Strait. 

The rescue team managed to attach a satellite tag to the fishing gear and the drag of the tag pulled off about 140 metres of poly-steel rope. 

The statement says the freed humpback, nicknamed Astroboy, is a Hawaiian whale that migrates to B.C. waters. 

The department says debris is a real problem for marine mammals. 

It says the public can help prevent entanglements by cutting packing material, banding, rope and other looped material before throwing it away and not putting it in the marine environment.