Science Spotlight

Since being signed into law in 1970, the California Endangered Species Act, or CESA, has proved to be a landmark law in a history of progressive wildlife conservation in California. It has been key in helping to stem the tide of species extinctions, raise public awareness about the plight of wildlife, and underscore the need to balance species conservation with economic development. CDFW is responsible for safeguarding the hundreds of CESA-listed species, and a key part of this mission is supporting and elevating the important research being conducted on these imperiled plants and animals.

The 2021 Special Issue of the California Fish and Wildlife Journal titled “The California Endangered Species Act: Successes and Challenges” contains a comprehensive collection of articles about the research, management and conservation of threatened and endangered species. At 473 pages, this is the largest Journal issue ever published! It includes 16 full research articles, five research notes, two review papers and four essays, altogether covering 25 species. Authors include CDFW staff, academic researchers, non-profit organizations and other conservation entities. Download the entire issue (PDF) or individual articles.

Topics covered in the issue include range expansions, new methods for species identification in the field and lab, reviews of habitat use and spatial occurrence patterns throughout California, results of management actions, benefits of long-term monitoring programs and planning strategies for conservation and recovery actions. The issue starts with a CESA Policy and Regulations section and follows with eight sections organized by taxa. Photos at the beginning of each section showcase California’s amazing biodiversity. For those new to CESA, an overview of the listing process is provided both in a detailed article and a simplified flowchart.

Article highlights include:

Amargosa Niterwort

Plants make up 158 of the 316 species currently listed under CESA. In this issue, Amargosa niterwort (Nitrophila mohavensis) takes the spotlight when authors share the value of a 10-year monitoring program for this alkali wetland plant, which occupies a total area less than 20 km2 in the northern Mojave Desert. Collaborative monitoring has resulted in a better understanding of the species, including phenology and abundance trends. This information could support conservation actions in response to threats such as groundwater alteration and off-highway vehicle impacts. For more details, see the article titled “Status of the Amargosa niterwort (Amaranthaceae) in California and Nevada.”

Bumble Bee Protection

In the article “A conservation conundrum: protecting bumble bees under the California Endangered Species Act,” authors Richard Hatfield and Sarina Jepson of the Xerces Society for Invertebrate Conservation present their view of the history and recent context of listing invertebrates under CESA. The authors argue that population declines driven by factors including climate change, insecticides and habitat loss have led to thirty percent of California’s bumblebee species facing extinction risk. In light of this, the Xerces Society and others have led a recent push to provide formal protections for several species of bumblebee. The article provides the authors’ overview of their 2018 petition to protect four imperiled bumblebee species under CESA and the subsequent legal complications that have unfolded.

California Tiger Salamander

“Use of atypical aquatic breeding habitat by the California Tiger Salamander” provides insight into this endangered species’ ability to reproduce outside of its historically associated habitat. Typically thought to reproduce only in vernal pools, researchers observed California tiger salamanders breeding in cattle stock ponds, intermittent creeks and rain-filled excavated depressions. Further investigation is needed to determine if these atypical breeding sites result in any reproductive success, as some have limited hydroperiods that may not be conducive to California tiger salamander metamorphosis. However, this study provides insight for the potential role of reproductive plasticity in the face of vernal pool habitat loss. For development projects within the range of the California tiger salamander, this study identifies additional habitat features that should be assessed when identifying and addressing potential impacts to this listed species.

We would like to thank the CDFW editorial staff for their hard work on this special issue. We also want to thank and acknowledge the researchers and authors of the articles, whose hard work to understand these imperiled species is helping bring them closer to recovery. The California Fish and Wildlife scientific journal has published high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife for more than 100 years. We look forward to the continued contributions in the next decade to come.

A coast yellow leptosiphon seedling.


Residential development on the San Mateo coast threatens coast yellow leptosiphon’s habitat.


Coast yellow leptosiphon is a low growing annual from the Phlox family which typically blooms in April and May.

The world is closing in on coast yellow leptosiphon.

The endangered plant exists in only one known location on earth — an 1,800 square foot plot on Vallemar Bluff in Moss Beach, about 20 miles south of San Francisco. The low-growing annual from the Phlox family features bright yellow flowers with fused petals and typically blooms in April and May.

Erosion caused by rain, waves and other factors is making the bluff that the plant perches on less stable. One study showed that the bluff receded 48 feet between 1908 and 2014. Scientists believe it will continue to recede almost six inches per year moving forward. Climate change could accelerate the erosion process.

“The plant could be almost completely gone in the next 50 years due to bluff-top erosion alone,” said Cherilyn Burton, a senior environmental scientist in CDFW’s Native Plant Program.

Slightly inland from where coast yellow leptosiphon grows is a planned four-unit housing development. The project was approved in March 2019. Although the development project mitigates for direct impacts to the plant, it also eliminates an area that could have been used to help restore the species.

Then there are the indirect impacts caused by urban development. Some aspects of urban design, like installation of storm drainage and landscape irrigation systems, could alter water runoff patterns around the plant’s habitat. The new housing development could also mean increased use of fertilizers, pesticides and other chemicals which through runoff could flow into the plant’s habitat and harm the soil.

“An increase in human activity can cause soil and habitat disturbances, which creates conditions that can be favorable to the spread of non-native plants,” said Burton.

Growing among the coast yellow leptosiphon is freeway iceplant—a fast-growing, invasive species that dominates the landscape and outcompetes other plants for light, nutrients, water, space and other resources. Coast yellow leptosiphon is also threatened by non-native plant species like rough cat’s ear, hare barley and cut leaf plantain. It may also face negative impacts from non-native slugs which can be detrimental to the plant’s seedlings.

“There’s so much going up against this plant. We may have to get creative to save it,” said Burton.

If there’s a bright spot in coast yellow leptosiphon’s story, it may be the lack of opposition in getting it listed as a protected species. In 2016, the California Fish and Game Commission designated coast yellow leptosiphon as a candidate species under the California Endangered Species Act. The plant was officially listed as an endangered species in 2018.

Burton recalls the heavy workload that came with preparing her recommendation to the Commission, and her relief upon hearing the Commission’s vote.

“They voted on it right then – right after I gave my presentation. Sometimes the commissioners have questions. But this time there was silence, and then one of the commissioners said, ‘Well, I think we can all agree that this plant meets the criteria.’”

Options to save coast yellow leptosiphon are limited, but there are a few. Scientists are on the lookout for additional suitable habitat. However, most suitable areas already contain rare and sensitive plants to which scientists must consider potential impacts. If additional suitable habitat is found, there will likely be land use and management issues to be worked out.

“The biggest problem is there’s just not a lot of habitat left in the area, and it’s not clear how far away we could go before the microclimate or other conditions would be too different to be suitable,” said Burton.

Another conservation strategy could include long-term seed storage at a botanical garden or other suitable facility to preserve seeds for the future.

Meanwhile, one landslide at the bluff’s edge could have serious consequences.

“Because of its vulnerability and rarity, losing any portion of the plant’s population could result in extinction,” said Burton.

CDFW Photo. Top Photo:
CDFW scientists Jeb Bjerke, Cherilyn Burton and Bill Condon (retired) at Moss Beach in San Mateo County doing fieldwork to support coast yellow leptosiphon.

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Media Contact:
Ken Paglia, CDFW Communications, (916) 825-7120

Lassics lupine grows under protective cages.


Richard Macedo, Habitat Conservation Planning Branch Chief constructs a cage to protect rare, endangered Lassics lupine.


Lassics lupine grows under protective cages.

Biologists from three government natural resource agencies banded together this summer in an unusual effort to help preserve a species under threat of extinction. They lugged materials to build wire cages into the rough terrain of the remote Lassics mountains near the border of Humboldt and Trinity counties in an effort to protect their target. However, these cages were not built to trap animals; they were constructed to keep animals out.

The barren, green serpentine slopes of Mount Lassic, located in a seldom-visited part of Six Rivers National Forest, are home to one of California’s rarest plants: the Lassics lupine (Lupinus constancei). Lassics lupine is a short plant in the pea family that has bright rose-pink flowers. Only approximately 450 adult Lassics lupine plants were observed during 2017 monitoring of the species conducted by the U.S. Forest Service and the U.S. Fish and Wildlife Service, with assistance from CDFW.

Rodents such as deer mice, squirrels and chipmunks have been eating so many Lassics lupine seeds from the plants that, absent intervention, the species appears to be on the path to extinction within the next 50 years (Kurkjian et al. 2016).

Biologists believe that historical suppression of fires in Six Rivers National Forest beginning in the early 1900s may be indirectly responsible for the encroachment of forest and chaparral into Lassics lupine habitat. Fires that were put out quickly did not grow large enough to reduce encroaching forest, and therefore the forest expanded. With the encroaching vegetation came more seed-eating rodents that depend on vegetation cover for protection from predators.

In 2003, the U.S. Forest Service, U.S. Fish and Wildlife Service and other researchers began an emergency attempt to halt Lassics lupine’s trend towards extinction. Each summer, biologists set off on the laborious hike up Mount Lassic to place cylindrical wire cages over as many flowering Lassics lupine plants as possible. Each cage is anchored to the ground to prevent rodents from squeezing underneath.

The cages are remarkably effective at stopping rodents when properly installed, and they remain on the plants for the duration of the growing season. After Lassics lupine fruits have matured, they often split open suddenly and send seeds flying through the air up to 13 feet away. The cages are then removed each year before the onset of winter snow.

“Protecting endangered species is California’s policy and plants like the Lassics lupine could disappear within our lifetimes,” explained Jeb Bjerke, a biologist with CDFW’s Native Plant Program. “We should do what we can to save these unique plants for the future.”

In 2015, in the midst of an historic drought, an 18,200-acre fire spread through the Lassics, killing many Lassics lupine plants and charring the chaparral vegetation nearby. The fire had little effect on the forest that encroaches into Lassics lupine habitat, but preliminary studies suggest that the fire may have reduced rodent density in the burned chaparral. Despite the apparent reduction in rodent density following the fire, the impact from rodents eating Lassics lupine seeds remains high. Continued caging of Lassics lupine plants therefore remains critical for preventing extinction of the species until a more permanent solution can be implemented, such as significant reduction of encroaching forest. However, such efforts are expensive to plan and implement. As the primary land manager, the U.S. Forest Service would likely be the lead agency in future protective actions.

In 2016, the California Fish and Game Commission received a petition to list Lassics lupine as an endangered species under the California Endangered Species Act and the species was designated a candidate species earlier this year. CDFW is in the process of producing a status review for Lassics lupine that will include a recommendation to the California Fish and Game Commission on whether listing the species is warranted. The legislature directs all state agencies, including CDFW, to seek the conservation of endangered and threatened species.

“I hope that CDFW can continue to partner with the U.S. Forest Service and U.S. Fish and Wildlife Service to protect the Lassics lupine from extinction,” Bjerke said.

For additional information on this subject, please see:

• Report to the Fish and Game Commission, Evaluation of the Petition from Mr. David Imper and Ms. Cynthia Elkins to List the Lassics Lupine (Lupinus constancei) as an Endangered Species under the California Endangered Species Act (PDF).
• Kurkjian, H.M., S.K. Carothers, and E.S. Jules. 2016. Seed predation has the potential to drive a rare plant to extinction. Journal of Applied Ecology 54:862–871.

California Department of Fish and Wildlife photos by Jeb Bjerke