The vernal pools are populated by two very rare species of animals: the vernal pool fairy shrimp and Santa Rosa fairy shrimp. One of the two species of fairy shrimp is found only here and nowhere else on Earth!
The Fairy shrimp live about a month and a half, then lay eggs called cysts that persist in the dry soil for months and often years before the next rain. The dormant embryos can survive and stay viable for centuries!
During their brief adult lives, the tiny, translucent crustaceans reach a half inch to an inch long. “They have 11 pairs of legs that swim gracefully through the water,” Rob Hicks, a Riverside County parks interpreter who works at the reserve said, “the most important old animal here,” is the fairy shrimp, because of its rarity and ability to survive a disappearing habitat.
https://www.pe.com/2019/02/15/rain-revives-santa-rosa-plateau-vernal-pools-near-murrieta/
On the boardwalk across the pools, visitors can see
fairy shrimp and maybe even the cysts. “You can see them in an egg
sac on the female before she lays them,” Hicks said.”
https://www.pe.com/2011/03/20/a-look-back-santa-rosa-plateau-home-to-shrimp/
There are 13 vernal pools on the Santa Rosa Plateau. Three are visible from the Vernal Pool Trail and the largest — a small lake spanning 25 acres — can be reached by walking the trail.
About 90 percent of Southern California’s vernal pools are gone, having been paved or plowed over for houses, shops and farms. The plateau has some of the largest remaining pools.
Santa Rosa Plateau Ecological Reserve, SRPER, is a ‘living museum of sensitive Southern California habitats. A museum of tenajas (deep, granite-lined pools), and woodlands of rare, rugged Englemann Oaks, of vernal pools, and native grasslands.”
SRPER is one of the most heavily visited ecological preserves managed by the Department of Fish and Game. Thousands of hikers, joggers, painters, photographers, horseback riders and school children go each year. I still remember the fieldtrip we took to the SRPER in elementary school- we got a glimpse of what California looked like before being developed.