Wild Horse Contraception Field Programs

Immunocontraception programs using PZP vaccine provide non-lethal population management for wild horses. Field delivery programs have demonstrated effectiveness at reducing population growth without roundups.

Key Facts

PZP contraceptive vaccine has a 90%+ efficacy rate in mares when delivered as a primary and booster dose
Remote dart delivery by trained volunteers enables PZP application without capture and its associated welfare costs
Annual population growth rates of 15-20% in untreated herds can be reduced to near zero with comprehensive PZP programs
Mares treated with PZP can be identified by ear notching or freeze branding allowing population monitoring

Welfare Considerations

Wild horse contraception through PZP delivery represents a welfare-superior alternative to roundups for managing population growth. Mares remain in their social groups with no separation from family bands. The vaccine is safe with minimal side effects. Field delivery programs that train volunteers to dart mares can cover large herds without professional staff for every treatment. The combination of effectiveness and welfare superiority makes PZP the most compelling management approach available.

What You Can Do

Support wild horse contraception programs including volunteer opportunities for trained PZP darting
Advocate for BLM adoption of PZP programs at scale as a welfare-superior alternative to roundups
Donate to organizations operating volunteer PZP programs for wild horse population management
Learn about wild horse contraception effectiveness evidence to engage with management policy debates