Some endangered species in Puget Sound are almost as big as a school bus. Others can fit in the palm of your hand--like the pinto abalone, a sea snail found around the San Juan Islands and the Strait of Juan de Fuca.

The Washington Fish and Wildlife Commission has declared the abalone an endangered species, a designation aimed at helping it bounce back from a long, steep decline.

Populations of the colorful and reportedly tasty sea snail around the San Juans have dropped 97 percent since 1992.

“Pretty adorable for an invertebrate,” biologist Hank Carson with the Washington Department of Fish and Wildlife said of the giant, flat snail with a bright red shell. “It’s got a couple little eyestalks and some tentacles that stick out the front, too."

While some Puget Sound species (think salmon) have landed on endangered-species lists after their habitat’s been destroyed, that’s not the case with abalones.

“There’s a lot of good habitat,” University of Washington biologist Carolyn Friedman said.

"The simplest answer is that we took too many. We harvested too many," Carson said.

Even after Washington banned abalone harvesting in 1994, the snails remained so scarce that they couldn’t reproduce.

Abalones living near each other on the sea floor spew their eggs and sperm into the water at the same time. Currents play Cupid with some of those gametes, and some of the resulting larvae eventually settle onto patches of rock.

With some kelp or other algae to graze on, and luck avoiding predators like sea otters and sunflower stars, they’ll grow into snails up to six inches across.

But so few abalones are spread over such a large area that the eggs and sperm rarely bump into each other any more.

“There has not been a good recruitment event for many decades,” Friedman said.

Carson said no one has seen a young, wild abalone in Washington for 11 years.