It’s been a rough year for whales off the coast of California.
Scientists with the National Oceanic and Atmospheric Administration say some 45 of them were spotted tangled in fishing gear in 2015, a record for the region. The list included humpback, gray, blue and fin whales.
Entanglement occurs when a whale swims into a line going from a buoy to a fishing trap on the sea floor. As the animal swims away, the trap can follow, eventually wrapping itself around the body.
"Commonly we see entanglements around the tail, the pectoral flippers and in the mouth," said Justin Viezbicke with NOAA.
The lines rarely kill the whales right away, but they can stay on an animal for years, interfering with feeding and causing infections, Viezbicke said.
"If it’s bad enough and on long enough, it can be lethal for the animal, so they can be very serious in nature," he said.
The last few years have seen an uptick in entanglements, according to NOAA which monitors whales along the West Coast. Part of the reason might be that boaters and beach goers are getting better at spotting the problem.
It could also be that unusually warm coastal water is changing where the whales swim, bringing them closer to traps.
Either way, Viezbicke said it’s very hard to free a whale once it's tangled.
Usually, a team will approach in a small boat. Using poles and special tools they try to clear lines and gear. However, whales often dive away making it hard to help. Viezbicke added that NOAA never sends divers to untangle whales since that can be very dangerous.
Last year NOAA only managed to help untangle around 6 whales.
Currently, NOAA is documenting these entanglements to find out how and where they happen. Viezbicke hopes this information will help researcher come up with strategies to prevent more entanglements from happening.