Rescuers are attempting to save a blue whale off the coast of southern California after it was spotted trailing fishing line and crab traps on Monday (27 June 2016). The rescue team was alerted after a whale-watching vessel spotted the giant mammal a few miles from Dana Point, California.

Sailors from a local whale-watching vessel who first spotted the creature said that they were surprised when seeing the mammal as it would only raise its head near the surface, instead of swimming and diving as normal. It was then that they noticed the line trailing from its tail, and they called the authorities.

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A report from the National Oceanic and Atmospheric Administration (NOAA) said that there were an average of eight reports of large whales being entangled each year off the coast of California between 2000 and 2012. The NOAA told NBC that they thought the whale was one that had been spotted in the San Diego area on Sunday: "It's trailing the same type of gear".

The whale is thought to be 70-80ft long and attached to around 200ft of line. Whales do not usually come so close to the shore, so these types of entanglements are rare. The NOAA said that 61 whales were reported entangled off the US West Coast (Washington, Oregon and California) in 2015.

The International Union for Conservation of Nature and Natural Resources (IUCN) classified blue whales as endangered and put the population at between 10,000 and 25,000 – around 3-11% of the population in 1911. Blue whales used to be the target of major commercial hunting, but have been a protect species since 1966.