Our Community, Our clean Water

Protect Our Open Space


A global diversity hotspot

The unspoiled San Mateo and upper San Juan creeks support a nearly extinct assemblage of native fish in southern California, including the arroyo chub, Southern Steelhead trout (pictured right) and threespine stickleback.


Protecting South Orange County Will Assist The Recovery of Numerous At-Risk Species

"It has long been my opinion that this area [southern Orange County] stands in a class by itself as our ONLY opportunity to conserve a large, unfragmented, ecologically intact portion of southern California's coastal ecosystems. The regional and global significance of this area cannot be overstated." Dr. Paul Beier, Northern Arizona University.

South Orange County and adjacent San Onofre State Beach form the heart of some of the world's rarest habitat. Numerous scientific studies have identified south-coastal California as a hotspot for species diversity, endemism, endangerment, and conservation priority.

  • More than half of the total remaining population of coastal cactus wrens left in the world
  • Seasonal population of the critically endangered southern steelhead trout-fewer than 500 survive in the world
  • As much as 25% of the remaining U.S. population of the California gnatcatcher
  • Over 330 nesting sites for hawks, owls, eagles and falcons
  • At least eight threatened and endangered species:
  • Southern steelhead trout
  • Arroyo toad
  • California gnatcatcher
  • Least Bell's vireo
  • Southwestern willow flycatcher
  • Riverside fairy shrimp
  • San Diego fairy shrimp
  • Tidewater goby

The Area Also Supports Rare Vegetation

  • The largest known populations of southern tarplant, many-stemmed dudleya, and intermediate mariposa lily (all listed as rare or endangered by California Native Plant Society).
  • Thread-leaved brodiaea (federally threatened, state listed as endangered).
  • Largest remaining alkali grasslands and wetlands in Southern California.
  • Among the largest and best remaining examples of California's native perennial grasslands, which have been reduced to about 0.1 percent of their original range.

Source: Conservation Biology Institute "On the Global and Regional Significance of Southern Orange County"

Robin Everett
Conservation Organizer
Sierra Club/Friends of the Foothills
949-361-7534 / fax: 949-361-6623