Marbled Murrelets Now Threatened in Santa Cruz Mountains State and County Parks

October 9, 2026

To:

• Santa Cruz District of California State Parks
  Chris Spohrer, District Superintendent

• San Mateo County Resource Conservation District
  Kellyx Nelson, Executive Director

• San Mateo County Parks Department
  Emma Gonzalez, Interim Parks Director

Re: Forest management operations underway in the Santa Cruz Mountains - California State Parks Forest Management Strategy and Appendices, San Mateo County Forest Health and Fire Resilience Public Works Plan and associated documents

The Pacific Seabird Group (PSG) recommends a modification of the forest fuel management program currently underway in the Santa Cruz Mountains (Marbled Murrelet Conservation Zone 6) that are associated with the implementation of the State Parks Department’s Forest Management Strategy, the San Mateo County Resource Conservation District’s Butano State Park Forest Health Project, and related plans. Some of the forest fuel reduction activities proposed and underway include tree felling by chain saws, log removal, mastication of vegetation, and the use of bulldozers and excavators. These activities are likely to have adverse impacts on Marbled Murrelets (Brachyramphus marmoratus) and their nesting habitat. These projects occur within sites occupied by nesting Marbled Murrelets, a federally-threatened and state-listed rare species, and, based on our scientific expertise, we believe that the murrelet harm avoidance measures in these plans fall short of their intended goals.

The Pacific Seabird Group (PSG) is a society of professional seabird researchers and managers dedicated to the study and conservation of seabirds. PSG was incorporated as a 501c3 non-profit in the state of California in 1972 and has an international membership from countries throughout the Pacific Basin and beyond. The principal goals of PSG are to: 1) increase the quality and quantity of seabird research by facilitating the exchange of information, 2) identify and assess the importance of threats to seabird populations, and 3) provide government agencies and others with expert advice on managing threats and populations. Over the last several decades, PSG members have provided Marbled Murrelet population status information, standardized monitoring protocols for at-sea and forest-based monitoring and assessed management alternatives for state and federal agencies and other constituents.

The forest management activities that concern us are those occurring within old-growth and bordering younger redwood stands in Butano State Park, Portola State Park, and surrounding areas. Long-term monitoring data confirms that these stands are occupied nesting sites. While we recognize that these fuel management plans aim to prevent catastrophic crown fires like the 2020 CZU fire — which destroyed an estimated 78% of murrelet nesting habitat in Big Basin State Park (Singer and Rinkert 2025) — it is vital to protect the remaining unburned or lightly burned stands. Fortunately, some suitable habitat remains in old-growth redwood stands outside Big Basin that were either unburned or lightly burned, including in Butano State Park, Portola State Park, and surrounding areas.

Our concern is with disturbances to nesting murrelets and their habitat (old-growth and occupied forest stands). Since only a minority of the total project work area is within old-growth stands, or occupied sites, we are only requesting a modification of the forest management actions in these areas. Specifically, we recommend:

• That no forest management work occurs within occupied stands and that an adequate buffer be established around those areas to protect them from noise or other impacts originating outside of the old-growth stand.

• Where there are occupied stands containing campgrounds, picnic areas, or other areas of significant human use, we support ground-based prescribed burning if it is done outside of the breeding season.

• We do not recommend any tree thinning in old-growth stands as this can remove the cover vegetation required to shield murrelet nests from predators.

Additionally, we identified several flaws in the supporting evidence presented in the Forest Management Strategy. As detailed in Table 1, the project's acoustic assessment used a methodology that significantly underestimates mechanical noise levels. Furthermore, the protocol inappropriately shortens the recognized breeding season based on the incorrect assumption that Audio-Visual (A/V) and Autonomous Recording Unit (ARU) acoustic data can precisely predict the onset or cessation of nesting activity. Table 1 outlines all our concerns and recommended solutions to the proposed forest management activities within the plans.

We wish to make it clear that we are not objecting to the total project. In this specific case, in the Santa Cruz Mountains, we can see the benefit of treating younger redwood stands that have previously been harvested. We also realize that much expense and effort have gone into planning and implementing this project. Consequently, we are limiting our objections to the bare minimum needed to protect the Marbled Murrelet. For example, we have no concerns about fuel reduction efforts going forward in Año Nuevo State Reserve or Big Basin State Park where very little suitable nesting habitat remains.

We appreciate State Parks’ historical dedication to conserving murrelet habitat and funding population monitoring in Zone 6. Modifying the current fuel management project is the most effective way to build upon these successful conservation efforts and ensure the long-term survival of the Zone 6 population.

We hope to hear back from you to discuss these areas of possible improvement in the Forest Management Strategy, and to collaborate on an amicable solution that balances wildfire resistance and resilience with the best available science for Marbled Murrelet conservation. Members of PSG’s Marbled Murrelet Technical Committee are readily available to provide additional scientific information and further discuss the suggested adjustments.

Sincerely,

Scott Pearson, PhD
Vice-chair for Conservation
Pacific Seabird Group

cc:

U.S. Fish and Wildlife Service Ventura Field Office
U.S. Fish and Wildlife Service Sacramento Field Office
California Department of Fish and Wildlife – regional office
California Coastal Commission – central coast district

Literature Cited:

Singer, S.W. and A. Rinkert. 2025. Impact of the 2020 CZU Fire on Marbled Murrelet nesting habitat in Big Basin State Park. Report prepared for the Santa Cruz District of California State Parks. Steven Singer Environmental & Ecological Services, Santa Cruz, CA. Available online at www.scmbc.org.