Center for Biological Diversity

Tucson, Arizona, USA (Owls Club building) · Offices in ten states and Washington, DC · 501(c)(3) nonprofit membership organization

Overview

The Center for Biological Diversity is an American nonprofit membership organization that uses legal action, scientific petitions, and creative media to protect endangered species and wild places — operating as one of the most litigious, and by its own accounting most successful, environmental law organizations in the United States. It was founded in 1989 beneath the ancient ponderosa pines of New Mexico's Gila Wilderness by Kierán Suckling, Peter Galvin, and Todd Schulke — three men in their early twenties who had met while surveying Mexican spotted owls for the US Forest Service. Suckling was a doctoral student in philosophy; Galvin was training in conservation biology; Schulke had a background running outdoor education programs for high-risk youth. A small grant from the Fund for Wild Nature and the passionate participation of Robin Silver — an emergency room doctor, nature photographer, and grassroots advocate who had already written an Endangered Species Act petition to protect the Mexican spotted owl — gave the group its initial shape. What began as a field-based advocacy effort in the Greater Gila region became, through thirty-five years of systematic legal work, a national organization with approximately 625,000 members and online activists, offices in ten states and Washington DC, and a documented record of securing ESA protections for more than 700 species and 713 million acres of critical habitat.

The organization is headquartered in Tucson's historic Owls Club building — a location whose name offers an unintentional but appropriate echo of the owl surveys that initiated the founders' work. Kierán Suckling remains executive director; Peter Galvin and Robin Silver remain on the board alongside writer Terry Tempest Williams and others. The founding philosophy — that the health of human societies depends fundamentally on biological diversity, and that the legal architecture of the Endangered Species Act, rigorously enforced, is the primary tool available for preventing extinctions in the United States — has remained constant through the organization's growth from three owl surveyors to a 200-person organization with an annual budget in the tens of millions of dollars.

Founding: Owls, the Forest Service, and an Act of Defiance

The founding story turns on a specific act of institutional defiance that crystallized what the Center would become. In 1989, Suckling, Galvin, and Schulke were employed by the US Forest Service to survey Mexican spotted owls in New Mexico's Gila National Forest — work that required them to locate owl nest sites and compile data on their population. In 1990, after completing a survey that identified owl nest locations near planned timber projects, they took the data to media outlets, alleging that the Forest Service was threatening the owls' habitat with nearby logging. The disclosure resulted in their contract terminations. Rather than moderating their approach, the three founders concluded that the experience had demonstrated exactly why an organization committed to outsider advocacy rather than collaborative negotiation was necessary: the Forest Service, as a timber-production agency, could not be trusted to protect the species it was mandated to survey. The confrontation became the organizational philosophy.

Their first formal action was an Endangered Species Act petition to protect the Mexican spotted owl — filed in 1989, before the organization had a formal name or legal status. The petition, which Silver had already been developing, was submitted in the organization's early days as the Greater Gila Biodiversity Project. The ESA requires the federal government to respond to petitions within fixed time windows; this legal forcing mechanism — using the Act's procedural requirements to compel agency action rather than simply requesting it — became the Center's signature strategy. The petition triggered the suspension of old-growth logging on federal lands across Arizona, New Mexico, and other states, and eventually led to the spotted owl's 1993 endangered listing and the halt of large-scale timber harvests on eleven national forests by 1995. The Center was formally incorporated as the Southwest Center for Biological Diversity on December 9, 1993, and later shortened its name to the Center for Biological Diversity.

Legal Strategy and the Endangered Species Act

The Center's core strategy is systematic, high-volume litigation under the Endangered Species Act combined with scientific petitions that trigger ESA's mandatory procedural timelines. Where many environmental organizations negotiate, the Center sues. Where many conservation groups seek collaborative relationships with federal agencies, the Center treats those agencies as adversaries to be compelled through legal action. This approach has generated both its extraordinary record of documented victories — more than 700 species protected, 713 million acres of critical habitat designated — and sustained criticism from industry, agriculture, and property rights advocates who characterize the Center as weaponizing the ESA for litigation revenue and to impose costs on landowners and resource-extraction industries.

The ESA petition process is the legal mechanism the Center uses most systematically: filing formal petitions to list species as threatened or endangered triggers a mandatory federal review process with specific deadlines. When agencies miss those deadlines — which, given chronic underfunding of the US Fish and Wildlife Service, happens regularly — the Center sues for compliance. The 2024 letter to Congress documenting a backlog of more than 300 species awaiting ESA review, with nearly 50 species having gone extinct while waiting for protection, is a direct product of this monitoring function: the Center tracks the entire pipeline of species needing federal protection and litigates missed deadlines as they accumulate.

The Trump Administration Litigations

The Center's litigation record against the first Trump administration — 266 lawsuits, with a win rate of 9 out of 10 resolved cases — is the most quantified illustration of its operational model available. The administration's environmental agenda, which included weakening ESA regulations, opening protected lands to resource extraction, and rolling back climate rules, generated a corresponding volume of legal challenges from the Center on virtually every front simultaneously: Willow oil drilling in Alaska, Pacific Islands Marine National Monument fishing access, coal mining reviews, ESA consultation regulations, critical habitat designations, and dozens of other specific actions.

The most significant legal outcome from those challenges resolved in March 2026, when a US District Court in the Northern District of California struck down four ESA regulations originally issued by the first Trump administration in 2019 — regulations that had weakened the processes for consulting about endangered species under Section 7 of the Act and for designating critical habitat under Section 4. The Center, Sierra Club, and WildEarth Guardians, represented by Earthjustice, had challenged those regulations; the court found them illegal and vacated them. The ruling directly affected the second Trump administration's own proposals to further weaken ESA regulations. Center attorney Ryan Shannon's statement was characteristically unsparing: "We're in an extinction crisis that demands urgent action to prevent thousands of animal and plant species from disappearing forever. Trump is hellbent on serving corporations at the expense of endangered wildlife, but thankfully the law protects these critters and the places they live. Now Trump must obey it."

The Center has simultaneously litigated against the second Trump administration on multiple new fronts — including a challenge to the Interior Department's invocation of the ESA's "God Squad" (the Endangered Species Committee) to approve fossil fuel development exemptions from ESA requirements, a March 2026 action that had not yet been resolved at the time of this writing.

Creative Media, Population Initiatives, and Broader Advocacy

The Center's name for its third pillar of work — "creative media" — signals that it sees communication and cultural work as integral to its mission rather than auxiliary to it. Its Endangered Species Condom campaign, which distributes free condoms decorated with endangered species imagery and messaging about the relationship between human population growth and biodiversity loss, has distributed millions of condom packets since 2009 and generated extensive media coverage. The Center has also conducted campaigns connecting biodiversity loss to climate change, industrial agriculture, and consumption patterns in ways that go beyond species-specific litigation to address the systemic drivers of extinction. Its annual State of the Birds and similar reports document the scale of biodiversity loss in formats accessible to general audiences. The Center maintains active social media presences and publishes regular press releases and news analysis through its own media operation.

Access and Membership

All Center for Biological Diversity publications, legal filings, species profiles, and press releases are freely accessible at biologicaldiversity.org. Membership — which supports the Center's legal and advocacy work — is available through the website. The Center's Trump administration lawsuit tracker, documenting all litigation against the current and prior administrations with case status and outcomes, is at biologicaldiversity.org/campaigns/trump_lawsuits. The Center's headquarters is at P.O. Box 710, Tucson, AZ 85702, in the historic Owls Club building.