Biodiversity, a combination of bio (life) and diversity, generally refers to the variety and variability of life on Earth.  Biodiversity typically measures variation at the genetic, the species, and the ecosystem level. No feature of Earth is more complex, dynamic, and varied than the layer of living organisms that occupy its surfaces and its seas, and no feature is experiencing more dramatic change at the hands of humans. This layer of living organisms—the biosphere—through the collective metabolic activities of its innumerable plants, animals, and microbes physically and chemically unites the atmosphere, geosphere, and hydrosphere into one environmental system within which millions of species, including humans, have thrived.

West Marin's biodiversity may be mostly characterized by the natural resources of Point Reyes National Seashore and the Golden Gate National Seashore, as it covers over half the region. Wildlife abounds in West Marin. Point Reyes National Seashore is as varied as the landscape itself, and ranges from large marine mammals such as the blue whale to the relatively small, endangered Myrtle's silverspot butterfly. In addition, the area is home to a broad spectrum of aquatic and terrestrial environments which support a diversity of plant communities such as forests, grasslands, coastal scrub, intertidal zones and marshes, coastal dunes and wetlands.

Since 1971, EAC has been actively advocating for the protection of biodiversity from Dillon to Muir beaches. Our work is focused on bringing people, science and policy together, to solve some of these threats and champion innovative solutions. For almost fifty years we’ve worked on various projects to protect vital ecosystems, defend critical legislation, enforce accountability of leaders and legislators and rally our community to become stewards of their backyard. Because a healthy watershed and ocean means a healthy planet.

habitat & species

Monarch Butterfly © Carlos Porrata

Monarch Butterfly © Carlos Porrata


Pesticide Spraying

Pesticide Spraying


2019 Coastal Clean Up & Litter Bug Me Roadside Trash © EAC

2019 Coastal Clean Up & Litter Bug Me Roadside Trash © EAC

Breathable air, potable water, fertile soils, productive lands, bountiful seas, climate and other ecosystem services are manifestations of the workings of life. It follows that large-scale human influences over this biota have tremendous impacts on human well-being. It also follows that the nature of these impacts, good or bad, is within the power of humans to influence.


  • 900 species of vascular plants
    (15% of all of California plants)

  • 61 endemic plants (found nowhere else on the planet)

  • 51 rare, threatened, or endangered species

Biodiversity Committee:

EAC’s committees provide expertise and advice on the complicated issues facing our environment. Our biodiversity committee examines issues that impact biodiversity, make recommendations to the EAC board and help guide staff decision-making. The Biodiversity Committee works on issues concerning habitat and species protection, pesticide use, and pollution.


Jerry Meral. Ph.D., Director
Sarah Killingsworth, Director
Claire Hutkins-Seda, Director


Morgan Patton, Executive Director
Ashely Eagle-Gibbs, Conservation Director
Karen Campbell, Education Coordinator


Mia Monroe

Learn more about West Marin's unique and irreplaceable landscapes and our colleagues:

Photographs by Carlos Porrata