The use of poisons for coyote control is controversial because of public opposition to lethal control of pest animals and the perceived environmental risks of pesticide use. The development of immunocontraception for population control of coyotes could result in a more acceptable alternative to poisons. Immunocontraception using porcine zona pellucida (PZP) would allow normal estrus in the female and therefore normal male-female pair-bonding. Coyotes are mon-estrus, therefore PZP contraception during the breeding season of February and March could provide year-round protection. This paper reviews 9 years of research on PZP immunocontraception, starting from a multi-shot PZP vaccine using Freund’s adjuvant, to the development and testing of two single-shot preparations combined with a newly developed adjuvant (AdjuVac™). We provide insights into the false assumption that one contraceptive vaccine fits all species and situations
