One Step Closer to State Protections
by Sophia Markowska
In a significant conservation gain, the Western burrowing owl (Athene cunicularia hypugaea) has been granted "candidate status" for protection under the California Endangered Species Act (CESA). The California Fish and Game Commission (Commission) voted unanimously in October 2024 to advance the species to candidacy after the California Department of Fish and Wildlife (CDFW) determined that the petition included sufficient information to indicate the listing of the species may be warranted. Burrowing owls will have CESA protections during the candidacy period, during which CDFW will undertake a complete status review of the species. This interim status is a crucial first step toward full protections under CESA, ensuring the species' long-term survival in the state.
Credit: Seth Topham
Bureau of Land Management
The petition seeking endangered or threatened status for the Western burrowing owl was filed in March 2024 by the Center for Biological Diversity, Defenders of Wildlife, Burrowing Owl Preservation Society, Santa Clara Valley Audubon Society, Urban Bird Foundation, Central Valley Bird Club, and San Bernardino Valley Audubon Society. It offers two potential CESA listing methods:
1. List the southwestern, central-western, and San Francisco Bay Area populations as endangered and the Central Valley and southern desert range as threatened
or,
2. List the burrowing owl as threatened throughout its entire range in California.
Background
Burrowing owls have experienced a dramatic decline in California, with populations disappearing from much of their historical range. They have suffered significant habitat loss due to urban development, the conversion of grasslands to agricultural lands, large-scale wind and solar energy infrastructure development, and the killing and removal of ground-dwelling squirrels and other mammals whose underground burrows the owls use for nesting and roosting. The owls are also killed by rodenticide poisoning and collisions with wind turbines and cars.
The species has been extirpated from at least 19 of the 51 counties where it once occurred, and is nearing localized extinction in 10 additional counties. Population losses began as early as the 1940s, with the decline accelerating since 2015. Currently, only about 225 breeding pairs remain in central-western and southwestern California and fewer than 1,500 breeding pairs are found in the Central Valley, primarily in the southern regions. A formerly large population in the Altamont Pass area in eastern Alameda and Contra Costa counties is down to a few hundred pairs and is declining rapidly. The San Francisco Bay Area population is near extirpation with less than 25 pairs around the margins of San Francisco Bay after emergency intervention.
The species’ stronghold is within the Imperial Valley, with an estimated 4,000 breeding pairs. Although there is still a relatively robust population in this region of southern California, banded burrowing owl data shows little evidence of movement between populations. This means burrowing owls in the Imperial Valley do not serve as a source population and do not augment geographically isolated or depleted populations elsewhere in the state.
Petition History
This recent petition follows a previously submitted petition in 2003 to list the burrowing owl under CESA by many of the same conservation co-petitioners as the 2024 petition. That petition was ultimately denied, with the state concluding there was insufficient evidence to warrant listing.
The Commission received the most recent petition on March 5, 2024. Once the Commission receives a petition, it must refer it to CDFW for evaluation. Within 90-120 days, CDFW must assess the petition’s contents to determine if sufficient information is included to indicate that the petitioned action may be warranted and, therefore, considered for listing.
CDFW found that the 2024 petition includes sufficient scientific information to indicate that listing the species may be warranted. On October 25th, the Commission published a decision to make the species a candidate for listing. Candidate status gives the burrowing owl interim state protections while the agency conducts a full status review, which can take 12 to 18 months to complete.
Problems with Current “Protections”
Prior to becoming a candidate species, the burrowing owl was only considered a Species of Special Concern. “Species of Special Concern” is a designation given to species that are not listed under CESA but satisfies one or more of the following criteria:
- Is extirpated from the State or, in the case of birds, is extirpated in its primary season or breeding role;
- is listed as Federally-, but not State-, threatened or endangered; meets the State definition of threatened or endangered but has not formally been listed;
- is experiencing, or formerly experienced, serious (non-cyclical) population declines or range retractions (not reversed) that, if continued or resumed, could qualify it for State threatened or endangered status;
- has naturally small populations exhibiting high susceptibility to risk from any factor(s), that if realized, could lead to declines that would qualify it for State threatened or endangered status.
Although the burrowing owl is a Species of Special Concern, current practices are insufficient to prevent or reverse population declines that have continued throughout most of the species’ range in California.
Many other means of protection have often been nonbinding and are also insufficient. For instance, CDFW has provided voluntary guidelines for avoidance, minimization, and mitigation measures for potential negative impacts on burrowing owls, but there is no requirement to abide by them. These guidelines often rely on the California Environmental Quality Act (CEQA) lead agencies to agree to adopt the measures. However, CEQA is not meant to be used as a tool for species and habitat protection, but rather as an information tool for policymakers to fully understand the environmental impacts of a proposed project. This leads to a frequent failure of the CEQA process to adequately mitigate for impacts to burrowing owls and their habitat.
In another attempt to protect the species, state and local governments have taken some steps to conserve burrowing owl populations through habitat preservation programs aimed at limiting the destruction of burrows. However, once again, these measures have not been mandatory nor have they been successful in reducing declines in the species’ populations. Burrowing owls are managed for in 36 Habitat Conservation Plans (HCPs) and 22 Natural Community Conservation Plans (NCCPs) in California, which include protection and mitigation measures. The permanent protection of habitat is one of the mitigation measures that is often utilized; however, these conservation lands are typically at a much lower ratio compared to the habitat that is being developed and are often piecemealed in a manner that disrupts connectivity between existing populations. Only a handful of these HCPs and NCCPs can point to any success in preserving burrowing owls, and few have the ability to protect large enough areas to support a meaningful number of breeding burrowing owls.
Current state policy allows for burrowing owls to be excluded from breeding sites after nesting to accommodate development projects. Studies show that this “passive eviction” is not a successful tool for mitigating project impacts, as many owls either don’t survive or don’t move on to breed elsewhere.
Petition Requirements for Listing Under CESA
In order for a species to be listed as threatened or endangered under CESA, petitioners must demonstrate that the species faces a significant risk of extinction. A petition must include substantial scientific evidence, such as the status of the species, population trends, habitat assessments, and threats to the species, to support the petition’s claim that a species should be listed.
For the Western burrowing owls in California, conservation organizations were able to build a strong case using data on the owl’s declining populations, the loss of suitable habitat, and the ongoing threats from urban development.
CDFW now has 12-18 months to produce a status report, based upon the best available scientific information, that will recommend to the Commission whether or not the petitioned action is warranted. This report will also incorporate public input and recommendations from burrowing owl experts. Then, based on the status report and other information in the administrative record, the Commission will make a final listing decision. If the formal decision is to list the species, burrowing owls will be granted full legal protection under CESA.
Conclusions
CESA protections for burrowing owls would require state and local agencies to better manage threats and fully mitigate impacts to the species. This would include ending the policy of evicting owls from burrows for development projects and requiring adequate compensatory mitigation for habitat loss. The recent progress in gaining candidate status for burrowing owls is a hopeful development for better conservation of the species. With formal protections and increased conservation actions from state agencies, the burrowing owl will have a fighting chance to rebound statewide.
Sophia Markowska is a Senior California Representative for Defenders of Wildlife. She works on imperiled species conservation and engages in a variety of renewable energy development issues on private lands within the Central Valley and California desert regions.
