California has passed a law in a desperate attempt to help record numbers of Pacific coast whales that are increasingly being so horribly entangled in crab pot lines and other fishing gear that they drown or slowly starve to death.

The Dungeness crab season was delayed and shortened this year because of a toxin linked to ocean warming. The shorter, more intense crabbing season occurred just as whales were feeding during their migrations around the area.

More whales ploughed through more heavy nylon lines connecting anchored crab pots to floats and became entangled. The line, or a set of lines, can wrap tightly around whales' flippers, dorsal fins or flukes, making it exhausting or impossible for the great beasts to swim. In some cases fins are amputated by the lines, or eyes gouged out.

The new law will provide a bounty for crab pots, and the potentially deadly line, often left behind or lost by crabbers.

"We want to reduce the suffering," Pieter Folkens, a member of the volunteer organisation California Whale Rescue, told IBTimes. "If we can't save these animals, some of them will take two months to die."

Between 2000 and 2012 an average of 10 large whale entanglements were reported off America's west coast each year, according to statistics from the National Oceanic and Atmospheric Association. In 2015 a record 61 entangled whales were found, up 90% over the previous year. Forty have already been spotted by June 2016 off California alone.

But those found are believed to be only 10% of the number affected, said Folkens. Many die in the deep ocean where they're not spotted nor can they be saved by small volunteer rescue crews that plie the Pacific coast looking for the distressed creatures.

The Whale Protection and Gear Retrieval Act will set up a fee-based system in which crabbers can recover abandoned ocean crab pots for a bounty. The owners of the registered gear will have to pay up to get it back or risk losing their fishing permits for the coming season. A commercial crab pot can cost several hundred dollars – more if it is attached to a long length of line.

The bill was backed by environmentalists and many crabbers who don't want to see the whales suffer.

The bill's sponsor, Healdsburg Democratic State Senator Mike McGuire, estimates that thousands of lost crab traps litter the California coastal ocean. Over the past two years alone, as part of a voluntary programme, 1,500 lost traps have been recovered by fishermen.

The new law is set to go into effect next year, covering Dungeness and rock crab fishermen throughout the state.

The entanglements are believed to be a side effect of global warming.