Science for a Blue Planet

Featuring cutting-edge work, discoveries, and challenges of our scientists, our partners, and the larger conservation science community.

Farallon Islands Restoration–How You Can Help

Note: While this post was originally published in July 2020, it was updated on June 21, 2021 to reflect the latest project developments. The post was additionally updated in December 2021. Updates have been added in italics.

We are at a critical moment in safeguarding the future of the Farallon Islands ecosystem and the wildlife that depend on it.  The US Fish and Wildlife Service, our partners in managing the islands, are considering an important decision and a significant opportunity for ecological restoration: the eradication of the invasive house mouse from the Farallon Islands. Point Blue would like to voice our strong support for this project. If you agree, we encourage you to do the same by submitting a public comment letter to the California Coastal Commission (CCC) letting them know you support the Service’s project to eradicate the invasive house mice. The CCC is likely to meet in the fall of 2021 to vote on the project and they need to hear from you! Please click the link below to show your support for their proposal (background below). We encourage you to customize the letter and please don’t forget to add your name at the bottom.

Email the California Coastal Commission

Consider submitting a comment letter to the California Coastal Commission (CCC) by 5pm Friday, December 10th, 2021.

Note: If the one click link above doesn’t launch a new email for you, please see alternative instructions at the bottom of this page.


View the recording of a webinar we participated in hosted by the Marin Audubon Society to hear from the experts themselves as well as reading over the information below.

Just over fifty years ago, biologists from Point Blue Conservation Science (known then as Point Reyes Bird Observatory) landed on the Farallon Islands for the first time. We have maintained a continuous presence on the islands ever since: 24 hours a day, 365 days a year. A year after arriving, the South Farallon Islands became part of the Farallon Islands National Wildlife Refuge and we entered into a unique, long-term partnership with the U.S. Fish and Wildlife Service (USFWS) to become stewards of the island and to provide baseline monitoring of the islands populations. Our role on the islands is simple: we use our expertise in biology, ecology, and conservation to provide rigorous science to the Service, helping them make decisions that will ensure a healthy ecosystem on the islands for generations to come. 

Referred to by some as “California’s Galapagos,” the Farallones host the largest seabird breeding colony in the contiguous United States and 25% percent of California’s breeding seabirds (more than 300,000 individuals of 13 species). Before human-caused disturbances, more than one million seabirds bred at the Farallones. Over the last 40 years, the USFWS has strived  to restore the Farallones by removing invasive plants and animals that have negatively impacted the island ecosystem. As an example, introduced, invasive cats and rabbits were removed in the 1970’s with positive ecological responses including the return of breeding rhinoceros auklets after a long absence.

Today, the invasive house mouse is the last invasive vertebrate remaining on the Farallones. Introduced by sailing vessels, likely in the 19th century, these mice exist on the islands in plague-like levels–at times reaching as many 1,270 mice per hectare, one of the highest observed densities in the world. The presence of invasive house mice is negatively impacting the Ashy Storm-petrel, other seabirds, Burrowing Owls, Farallon arboreal salamanders, Farallon camel crickets, and the islands’ vegetation. Threats to the rare and threatened Ashy Storm-petrel’s declining population are of particular concern. 

Thirteen years ago, the USFWS began a thorough review of available options to remove mice from the island. In the spring of 2019, the Service published one of the most thorough and scientifically rigorous Environmental Impact Statements on record, extensively referencing original, peer-reviewed science by Point Blue. The final product represents over a decade of careful study, with a final report of 322 pages supported by an appendix 577 pages long. Before publishing the final EIS document, USFWS reviewed each of the 553 public comments that were made on the draft EIS and addressed all substantive comments in its final report.

Invasive rodent removals have been successfully completed on nearly 700 islands worldwide. Land managers have successfully eradicated house mice from more than 60 islands worldwide. Nearly all of these successful projects utilized techniques like those proposed for the South Farallon Islands house mouse eradication.

The Farallon Islands are a world-famous local treasure. The USFWS has a unique opportunity in this moment to take a giant step forward in restoring the island’s fragile ecosystem and protecting the many species that rely on it. We applaud the USFWS for their careful, transparent process and their commitment to science-based decision making. Based on our fifty years of experience studying birds and other wildlife on the islands, we strongly support the conclusions of the Service’s EIS and hope you’ll do the same.

Addressing misinformation and misleading statements

Point Blue is aware that critics of this project have been spreading misinformation and misleading statements. Please visit this page where we clarify some of the important issues regarding the proposed project.

Selected Point Blue Science Contributions

Over the 50+ years that Point Blue scientists have been living on and studying the Farallon Islands, our original science has produced numerous peer-reviewed papers. Some of these have been used by the US Fish and Wildlife Service in the preparation of their Final Environmental Impact Statement and in the planning of this proposed restoration action. These include (but are not limited to) the following publications and reports:

Further Information

More information about the project including a FAQ, photos and videos, and official documentation from the USFWS can be found at the project website:

Sample letter contents and instructions

If the links above don’t work to start a new email to the California Coastal Commission, you can see sample letter contents below, but we encourage you to customize your letter. Please send letters to with the subject line: “Support for Farallon Islands Mouse Eradication Plan”.

Dear Commissioner,

I am writing to request that you approve the upcoming request for a consistency determination for the US Fish and Wildlife Service’s plan to remove invasive house mice from the Farallon Islands.

The introduction of invasive, non-native house mice to the Farallon Islands has caused significant disturbance to the islands’ sensitive ecosystem. The house mice have direct and indirect harmful impacts on the islands’ breeding seabirds, especially ashy storm-petrels, but also on Leach’s storm-petrels, as well as on native salamanders, crickets and other invertebrates, and native plants.

The only way to allow the ecosystem to recover is to ensure 100% eradication of the house mice. The survival of even a single pair of mice jeopardizes the whole project, as the mouse population can recover incredibly quickly.

At present, there is only one known method that has proven effective for island eradications, and that is the “preferred alternative” (an aerial broadcast of the rodenticide Brodifacoum) identified by the US Fish and Wildlife Service in the Final Environmental Impact Statement published in March 2019.

Thank you for your consideration and for following the best available science when making your decision.