There are no approved contraceptive products for mice, and the Farallon Islands are too important to use an untested solution. If there was a contraceptive bait approved for use, fertility control is still not an appropriate solution for restoring the Farallon Islands for multiple reasons, including:
- Contraceptives only cause temporary infertility and must be introduced into the ecosystem regularly and permanently to continue controlling the population
- Any contraceptive would need to be developed and approved for use in a bait form so it could be available to all mice around the island, and this type of product has not been developed
- If a solid bait were developed, it would need to be delivered by aerial broadcast to reach the inaccessible parts of the islands. The disturbance caused to Farallon seabirds and marine mammals by multiple drops per year would have catastrophic impacts.