Vernal Pools – Regional

Vernal Pools of California
Although they were once plentiful, more than 90% of the vernal pools in California have disappeared.  The remaining 10% still exist where conditions are favorable; namely in the Central Valley, the lower foothills of the Sierra Nevada, parts of Riverside and the eastern valleys of the mountains between San Luis Obispo and Monterey.  Most importantly for our area, they exist on many terraces and mesas along the California coast.

Vernal Pools of Santa Barbara
Vernal pools of the Santa Barbara area occur immediately west of the city at the coastal sites of More Mesa, Isla Vista and Ellwood Mesa.  Each of these areas sits on the south side of the More Ranch Fault, a geologic feature along which the coastal zone has been uplifted to create relatively flat topography, at sites having minor depressions and an impermeable clay layer in the soil.

camino corto
Vernal pool in Camino Corto Open Space, Isla Vista, May 01, 2011

Vernal Pool of More Mesa
More Mesa has one documented vernal pool, located above the ocean bluff at the southeastern corner of the mesa.  A dense stand of Harding grass, a robust naturalized plant, surrounds the pool, but several uncommon vernal pool species may occur within it.

more mesa
Vernal pool in SE corner of More Mesa, April 26, 2011