People often speculate as to the frequency of coyote-dog hybrids, or coydogs, in urban settings. Coyotes and dogs are related, and they are biologically capable of producing hybrid litters. Coydogs have been raised in captivity. Genetic surveys of wild coyotes have rarely documented evidence of dogs in the genetic makeup of coyotes, despite domestic dogs and coyotes sharing the continent for the past 9,000 years. Although it is possible, coydogs in urban settings are unlikely because:
- Coyotes are highly seasonal breeders; dogs are not.
- Coydog females have a shifted estrus cycle that does not coincide with the coyote period.
- Domestic dog and coydog males do not tend to litters, whereas male coyotes do.
- Coydogs may have lower fertility than either domestic dogs or coyotes.