This is a story about a humpback whale in distress, with a happy ending. The enormous cetacean was spotted off the coast of northern California last Tuesday, tangled in fishing lines and buoy and anchor lines that were steadily dragging it down beneath the waves. By Thursday, it was struggling to breathe.

A successful rescue

A team of rescuers with marine veterinarians, researchers, fishermen, and USCG spent eight hours cutting away the tangle, which included two fishing lines running through the whale’s mouth, fishing buoys wrapped around a fin and an anchor line that was pulling the tail down.

Once rescued, the whale swam in a circle the rescue boat before heading off into deeper waters. The rescuers believe it was thanking them for their help.

This is the seventh such case of a humpback whale becoming entangled in fishing lines off the west coast this year. Last year, 54 humpbacks were caught and tangled in crabbing gear. The lines this humpback whale was tangled in are believed to come from shrimping vessels, and the National Oceanic and Atmospheric Administration is trying to identify the boats responsible.

Fishing lines endanger marine life

Environmental groups are pushing for regulations to stop the practice of fishing vessels dumping old and damaged nets, lines and other gear overboard, where it endangers marine life.

According to the International Whaling Commission, as many as 308,000 Whales and dolphins are killed each year when they become entangled in fishing gear, due to injuries, drowning, infections and starvation. Marine debris can lead to even more fatalities.

Rescuing entangled whales can be dangerous since a trapped and injured animal can behave unpredictably.

A Canadian rescuer was killed on July 10 while untangling a North American right whale off the coast of New Brunswick. North American right whales can weigh up to 79 tons and are an endangered species.

On June 28, the non-profit Center for Biological Diversity filed a letter of intent to sue the California Department of Fish and Wildlife for failing to protect endangered species like whales and sea turtles.

The Department of Fish and Wildlife manages fisheries off coastal waters. Fishermen can prevent entanglements and save lives by reducing the number of trailer buoys and removing discarded fishing gear from the water, but at present compliance with such practices is only voluntary and not widely followed.