Calavera Hills/Robertson Ranch/EW

Area: The Calavera Hills/Robertson Ranch/EW Preserve consists of 237 acres in the city of Carlsbad in San Diego County.

Location: Carlsbad in San Diego County, CA

Date Acquired: 2006-2007

Acquisition Type: CNLM holds a conservation easement and has management responsibilities to protecting the species and habitat in perpetuity on the Preserve.

Key Habitats: Coastal Sage Scrub and Valley Foothill Riparian.

Species of Special Interest to CNLM: Coastal California gnatcatcher (Polioptila californica californica), Least Bell’s vireo (Vireo bellii pusillus) and Thread-leaved brodiaea (Brodiaea filifolia).


The Calavera Hills-Roberston Ranch Preserve (or Habitat Conservation Area) was set aside between 2006 and 2007. CNLM received the twoproperties from McMillinHomes and the Robertson Family Trust as part of their mitigation obligations forthe Calavera Hills and Robertson Ranch housing developments.

Conservation Significance

This Preserve supports a number of habitat types, including Valley Foothill Riparian, California Annual and Perennial Grassland, and Coastal Scrub.. These habitats support sensitive plant and animal species, including   the federally listed coastal California gnatcatcher (Polioptila californica californica), least Bell’s vireo (Vireo bellii pusillus), and thread-leaved brodiaea (Brodiaea filifolia).  The recently rediscovered Wiggin’s cryptantha (Cryptantha wigginsii) was found here.  Finding a species once thought extinct is an indication that long-term management by skilled conservation biologists uncovers unexpected and important discoveries.


Our Work

Our primary goal on the Calavera Hills and Robertson Ranch Preserve is to ensure continuation of healthy habitats that are necessary for the survival of the rare species, including the Coastal California Gnatcatcher, Least Bell’s vireo, and the Thread-leaved brodiaea.  These efforts include reducing the known threats to these species, monitoring populations, restoring the habitats, and research aimed at better understanding the biology of these species.  These activities will not only expand our understanding but will also increase our ability to make better conservation decisions, improving habitats which will lead to better survival rates.

Public Access

There are two public trails on this Preserve. One trail is located near  Village H, just off Carlsbad Village Drive;   second is located  at the intersection of College and Carlsbad Village Drive and leads to Lake Calavera (Village U).    


For information on Calavera Hills or Center for Natural Lands Management please contact Brooke Prentice-Dekker, Preserve Manager at or 760.731.7790 extension 221

Near intersection of College and Carlsbad Village Drive (and leads to Lake Calavera)

Near Village H (off of Carlsbad Village Drive)