Opposition is Broad in Santa Catalina Island Deer Eradication Plan

Most Californians would be shocked to learn that a plan is moving forward to eradicate every last mule deer from Santa Catalina Island. Not to reduce the herd to a sustainable level, not to implement science-based population objectives, but to eliminate the entire population.

The Catalina Island Conservancy has proposed—and state officials have approved—a multi-year eradication program for the island’s roughly 1,800–2,000 non-native mule deer, despite widespread public opposition, pending litigation, and legitimate questions about the necessity of total removal.

Mule deer were introduced to the island in the late 1920s and early 1930s for recreational hunting. They have been part of Catalina’s landscape for nearly a century. California law recognizes the value of mule deer and encourages their conservation and responsible management. Yet here, a long-established population faces complete extermination.

Opposition is broad: hunters, animal welfare advocates, many Catalina residents, visitors, Los Angeles County Supervisor Janice Hahn, and others stand united. Even some conservation professionals question whether total eradication is the only viable path.

The Science of Impacts—and the Gaps

The Conservancy cites peer-reviewed studies showing deer browsing harms native vegetation. Post-2007 fire research documented an eight-fold increase in shrub mortality where deer had access versus exclosures. Exclusion experiments demonstrate better growth and seed production for certain endemic plants, such as the Catalina Island mountain-mahogany. Deer are also said to facilitate invasive grasses, potentially elevating wildfire risk by altering vegetation structure in this Very High Fire Hazard Severity Zone.

These findings deserve serious weight on an island ecosystem lacking natural predators. However, critics—including wildlife biologists who reviewed the Conservancy’s data—argue that population estimates may be inflated due to survey methodologies, that historic livestock damage and drought play larger roles than acknowledged, and that the causal link to island-wide wildfire risk requires more robust, independent analysis. Past CDFW reviews (e.g., 2007) noted that habitat conditions stem significantly from centuries of livestock impacts, not solely deer.

The core question remains unanswered with full transparency: What is the island’s ecological carrying capacity for deer? Where is the independent, peer-reviewed assessment that rules out a managed population at, for example, 300–800 animals in less sensitive zones, combined with targeted protections? Without clearer benchmarks and long-term monitoring data, eradication risks becoming a default rather than a demonstrated necessity.

Concrete Alternatives That Merit Rigorous Evaluation

The Conservancy maintains that alternatives were considered and found insufficient. Yet public records and stakeholder input suggest several warrant deeper investment before irreversible action:

• Science-based regulated hunting: The 2024 season yielded only 379 deer harvested despite 754 tags issued—far below levels needed for control (studies suggest 50%+ annual removal of does for meaningful reduction). Recommendations include more tags, incentives for harvesting females, extended seasons, guided efforts focused on population modeling, and integration with Private Lands Management (PLM) principles. A 5-year adaptive management study, as proposed by hunting groups, could test whether a target density supports habitat recovery.
• Targeted fencing and habitat zoning: Existing island fencing could be extended or reinforced around high-priority rare plant communities and post-fire recovery zones. Rotational or permanent exclosures, paired with monitoring, have proven effective locally and could allow a reduced herd elsewhere.
• Fertility control (immunocontraception): While challenging at full scale, PZP or similar methods could be piloted in accessible areas (e.g., near Avalon) to slow growth while hunting reduces numbers. A hybrid approach—initial reduction followed by maintenance contraception—has been used elsewhere.
• Strategic relocation: Though logistically difficult and with welfare risks (high post-release mortality in past efforts like Angel Island), selective relocation of some animals to suitable mainland or other sites could be explored under veterinary oversight, prioritizing disease screening.
• Integrated adaptive management: Establish independent scientific oversight, set measurable objectives (e.g., native plant cover thresholds, deer density targets), and use tools like detection dogs, thermal imaging, and public hunting in combination. Monitor outcomes transparently with annual reports.

These are not untested ideas; similar balanced strategies succeed across North America for deer, elk, and other species on complex landscapes.

Ethics, Methods, and Public Trust

The shift to ground-based professional sharpshooting (after dropping helicopter plans) is an improvement for safety, but many still see a profound ethical gap between fair-chase hunting—with its emphasis on respect, utilization of meat (some planned for condor feeding), and sustainability—and a systematic eradication campaign. Catalina is not a remote wilderness; it is a living community and major tourist destination. Decisions of this scale demand openness.

The public deserves a full, transparent process—including robust CEQA-level review if litigation proceeds—rather than reliance on restoration exemptions. True stewardship balances habitat restoration with wildlife values, not a false choice between the two.

California has led in conservation through innovation and compromise. The Department of Fish and Wildlife should immediately pause full-scale eradication. Convene an independent scientific panel to assess carrying capacity, rigorously test alternatives, and develop a transparent management plan with stakeholder input. Once eradicated, this population cannot be restored.

We can protect Catalina’s unique ecology without erasing a century of wildlife heritage. Science-based management, not extermination, honors California’s conservation legacy. The evidence supports pursuing better options first.

Co-authored with Bill Gaines of GAINES & ASSOCIATES Government Relations.