A reef of glass sponges, creating a deep-sea oasis 650 feet below the surface, was discovered for the first time in U.S. waters off the Washington coast.

The sponges are so rich with marine life that scientists call them “a kindergarten or living hotel.”

All variety of baby organisms thrive among the reef of yellow and orange sponges, which look something like hollowed-out, supersized Cheetos.

These “Manhattans of the sea floor” house a diversity of starfish, crabs, shrimp, rockfish, worms and snails.

“It's like being in a very fancy aquarium in an expensive Japanese restaurant,” said Paul Johnson, the University of Washington geologist who found the reef this summer about 30 miles west of Grays Harbor.

Researchers didn't even think the oxymoronic structures - sponges made of glass that form reefs - even existed anymore. Captured in the fossil record, they were thought until fairly recently to have gone extinct 100 million years ago.

They were supposed to have been squeezed out by the arrival of microscopic marine algae that began gobbling up the glassy silica the sponges need to build their skeletons.

Instead, the crafty creatures went to depths too dark for the tiny plants - but not so deep that they couldn't get enough oxygen. There, the 1 1/2-foot-tall organisms built reefs.

When the sponges die - and they can live for a century - the next generation grows on top of them. The Washington reef is at least 2,000 feet long and up to 10 feet tall.

Glass sponge reefs were found in British Columbia about two decades ago, but in more inland waters.

“Discovering more sponge reefs on the Pacific Coast it's a really exciting discovery,” said Susanna Fuller, a sponge expert and graduate student at Dalhousie University in Nova Scotia.

It's been an exciting time for local marine biologists. In recent years, they've also encountered for the first time deep sea corals - both hard and soft - off the coast.

“This points to the possibility that there is more out there to be discovered,” said Fan Tsao, a conservation scientist with the Marine Conservation Biology Institute, a Bellevue nonprofit group.

An intriguing twist on Johnson's finding was the presence of natural gas, or methane. The methane is seeping out of the ocean floor, feeding strands of bacteria.

The glass sponges suck and sweep the bacteria in through their pores and eat them, jetting the extra water back out the hole at the top of their body.

“Everybody is feeding off the methane,” said Johnson, who plans to submit the findings to a scientific journal. “It's a whole ecosystem that people didn't know about.”

And Johnson is something of an unlikely character to have discovered it. A professor with the School of Oceanography, he had investigated superhot underwater hydro vents for 31 years.

Sponges were a bit of a stretch.

“I didn't have any idea of what a glass sponge was,” he said. “I thought it was something you did the dishes with.”

Johnson was introduced to the creatures while on a Canadian science expedition two years ago and got hooked.

He wondered if they were in Washington, too, and asked to look at some underwater maps made by a UW grad student working on an unrelated project. In the images, he saw what might be sponge reefs.

With financing from the UW Oceanography Department and the federally created Washington Sea Grant Program, he set sail in June for a five-day tour to see what he could find.

His 12-member research crew, while not quite motley, was a little random, dominated by less-experienced undergraduate students and an old pal of Johnson's who is a retired Catholic monk.

Using echo-sounders they searched the sea bottom, with no sponge to be found. Then they noticed a cluster of long-line fishing boats.

Fishing boats meant that fish were hanging around, and that meant that the fish had a home in the otherwise barren stretch of the ocean - the sponges.

Jackpot.

“It was fun when we found” the sponges, said Marie Salmi, a UW junior studying oceanography. “We were dancing around.”

To retrieve the glass sponges, the researchers lowered giant clamshell-like devices that scooped up sponges, dead and alive.

They took care not to damage the fragile creatures. Others might not be so cautious. The Canadian reefs are permanently protected from trawling, a method of fishing in which a net is pulled along the seabed, potentially obliterating the reefs.

Trawling in the area of the U.S. glass sponge reef is not allowed because of protections for struggling populations of rockfish, but that could change.

Canadian conservationists on Friday urged the creation of permanent and enforceable protections for the U.S. reef. It's a move that Johnson would support, considering the age of the glass sponges and ecological importance of the reef.

Allowing trawling or harmful activities in the area of the reef, he said, “it's like taking a chain saw to a redwood forest.”