A boat with Captain Dave’s Dolphin and Whale Safari reported a behemoth 80-foot blue whale swimming off the coast of Orange County on Monday afternoon, its massive body entangled in Dungeness crab traps and lines still attached to bright orange buoys.

A passenger on board shot live video of the encounter, posted to the safari’s Facebook page, which shows the animal laboring under the weight of the heavy netting. The harness was stuck in the whales mouth, safari captain Dave Anderson told Reuters, and the main rigging of the trap dragged beneath the animal.

In a first of its kind attempt on the West Coast to free a blue whale, an endangered species that officials say rarely becomes entangled, a fleet of rescue boats from local business and law enforcement set out into the Pacific. For hours on Monday, they tracked the struggling whale, Reuters reported, at times getting close enough to dip long poles into the water while the animal surfaced to breathe. At the end of the pole were cutters, used to slice away at the entanglement.

But the whale grew agitated, officials said, and eventually dove deep below the surface and out of sight. Rescuers stopped looking at nightfall, removing a tracking device they’d placed on the whale, reported CNN, and vowing to resume their search the following day.

But by the end of the day Tuesday, rescuers were unable to relocate the whale and remove the entanglement, according to an update on the safari Facebook page.

“The whale was last seen heading south, and NOAA has alerted San Diego, but the whale could be anywhere,” a post on the page said.

“Every move that whale makes is going to saw into that whale’s flukes. It’s going to be excruciating pain for that whale,” Anderson told CBS News.

The captain estimated the whale could only survive about 30 days, CBS reported, because the lines prevent the whale from eating or swimming freely. He expressed frustration that the rescuers were so close to cutting it free but failed.

“We were inches away from it, and I can tell you it was gut-wrenching that we couldn’t save it,” Anderson told the network.

Entanglements in blue whales are uncommon because it is unusual for them to venture near the coast, Michael Milstein, a spokesman for the National Oceanic and Atmospheric Administration (NOAA), told Reuters. The object of this rescue mission was only the second reported blue whale entanglement spotted off the west coast, he said, and the first time officials tried to free one.

Justin Viezbicke, with NOAA, is leading the rescue team, according to the Los Angeles chapter of the American Cetacean Society. He told CBS that reports of trapped whales are growing each year.

In 2015, NOAA confirmed 48 of the 61 whale entanglements reported off the coasts of Washington, Oregon and California, the highest annual total since it started keeping records in 1982, according to a press release. The Center for Biological Diversity reports that NOAA confirmed just 30 entanglements in 2014, up from an average of eight per year the previous decade, and three per year the decade before that.

According to those reports, the increase could be attributed to “changes in whale abundance and distribution, shifting patterns in fishing and other human activities, and increased public reporting.”

The global population of the endangered blue whale has depleted greatly, according to the International Union for Conservation of Nature, and has shrunk by at least 70 percent over the last three generations.

“There are not a lot of blue whales out there,” Anderson told CBS. “So we can’t afford to be losing any of them.”

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