A sea urchin dubbed the “cockroach of the ocean” has almost completely destroyed the kelp forests off the coast of Northern California — endangering the regions biodiversity and local economy. And it's all because of climate change.

The majestic vistas of the northern Californian coastline conceal an underwater slaughter that is troubling scientists and endangering local fishermen.

Early on a gray summer Saturday, an unusual assemblage — commercial fishermen, recreational boaters, neoprene-clad divers — gathered for a mission at Albion Cove, a three-hour drive north of San Francisco.

Too many purple sea urchins and not enough bull kelp continues to stymie California’s red urchin dive industry. Since the one-two punch of El Niño and the warm-water blob in 2016, bull kelp beds have declined by 93 percent from previous years, according to a study by the California Fish and Game Commission.

The spiny California sea urchin has busted out of the sushi bar and is having its moment on just about every menu in Los Angeles right now, in everything from uni jam to uni ice cream.

You might know them as ozzy eggs, but maybe they'd be better referred to as a cash cow.