Two Desert Thrashers Now CESA Candidate Species: Bendire’s And LeConte’s Thrashers Receive Interim Protection

On April 16, 2026, the California Fish and Game Commission voted unanimously to designate Bendire’s thrasher (Toxostoma bendirei) and LeConte’s thrasher (Toxostoma lecontei) as candidate species under the California Endangered Species Act (CESA). Candidate status triggers full CESA protections while the California Department of Fish and Wildlife (CDFW) completes a status review and the Commission considers whether to formally list the species as threatened or endangered.

This post summarizes the legal effect of the Commission’s decision, the procedural posture of the listing process, and key biological information about these desert songbirds.

What Does the CESA Candidate Listing Decision Mean?

Under CESA, species designated as “candidates” for listing receive the same substantive protections as formally listed threatened or endangered species for the duration of the review period.

In practical terms:

• The CESA prohibition on “take” now applies to Bendire’s thrasher and LeConte’s thrasher in California.
• “Take” includes actions that kill or capture individuals and can also include certain forms of habitat modification that directly result in mortality or injury.
• Projects and activities that may result in take of either species are now required to get authorization from CDFW, typically through an incidental take permit under Fish and Game Code section 2081 or another applicable mechanism.
• The candidate protections will remain in place until the Commission adopts a final listing determination.

Project proponents in the Mojave Desert, Sonoran Desert, and San Joaquin Valley—in particular those developing large‑scale renewable energy, infrastructure, or other ground‑disturbing projects—should consider the presence or potential presence of these species in their CESA compliance strategies.

Who Requested the Listing?

The Center for Biological Diversity (CBD) petitioned the Commission to list both Bendire’s thrasher and LeConte’s thrasher under CESA, asserting that each species has lost substantial portions of its U.S. population as a result of:

• Habitat loss and fragmentation from urban and exurban sprawl,
• Large‑scale solar energy development and related infrastructure,
• Off‑road vehicle and recreational impacts,
• Invasive plant species, and
• Altered wildfire regimes.

CBD also submitted petitions to the U.S. Fish and Wildlife Service (USFWS) to list Bendire’s thrasher and LeConte’s thrasher as threatened or endangered under the federal Endangered Species Act. USFWS has not yet issued an initial determination regarding either federal petition.

Where Are We in the CESA Listing Process?

The Commission first evaluated CBD’s state petitions through the 90‑day petition process for each species (Bendire’s thrasher and LeConte’s thrasher) and concluded that there is sufficient scientific information to indicate that listing may be warranted.

Following those initial evaluations, on April 16, 2026, the Commission voted to designate Bendire’s thrasher and LeConte’s thrasher as candidate species under CESA. As a result:

• CDFW now has 12 to 18 months to complete a formal, peer‑reviewed status report for each species.
• The status report will assess the best available scientific information regarding the species’ population status, threats, and conservation needs.
• After CDFW submits its status report, the Commission will hold additional public hearings and determine whether listing each species as threatened or endangered under CESA is warranted.

The relevant statutory timeline is set forth in California Fish and Game Code section 2074.6.

What Do We Know About Bendire’s and LeConte’s Thrashers?

Bendire’s Thrasher

Bendire’s thrasher is a medium‑sized, migratory songbird. Its range includes Arizona, California, Colorado, New Mexico, Utah, and northwestern Mexico. Approximately 5% of the global population (4,400 individuals) reside in California, primarily in the Mojave Basin and Range and the Sonoran Desert.

LeConte’s Thrasher

LeConte’s thrasher is a non‑migratory, medium‑sized songbird whose range includes Arizona, California, Nevada, Utah, and northwestern Mexico. Approximately 82% of the global population (37,000 individuals) reside in California, primarily in the San Joaquin Valley, Mojave Desert, and Sonoran Desert.

Key Takeaways for Project Proponents and Landowners

• Bendire’s thrasher and LeConte’s thrasher now receive full CESA protection as candidate species.
• Activities that may result in take of either species—or significantly modify occupied habitat—may require CDFW authorization.
• CDFW will have 12 to 18 months to complete a formal peer reviewed report on the two species.

Nossaman will continue to monitor the CESA and federal ESA processes for these species and provide updates as CDFW and USFWS take further action.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.