Size-assortative choice and mate availability influences hybridization between red wolves (Canis rufus) and coyotes (Canis latrans)

Anthropogenic hybridization of historically isolated taxa has become a primary conservation challenge for many imperiled species. Indeed, hybridization between red wolves (Canis rufus) and coyotes (Canis latrans) poses a significant challenge to red wolf recovery. We considered 7 hypotheses to assess factors influencing hybridization between red wolves and coyotes via pair-bonding between the two species. Because long-term monogamy and defense of all-purpose territories are core characteristics of both species, mate choice has long-term consequences. Therefore, red wolves may choose similar-sized mates to acquire partners that behave similarly to themselves in use of space and diet. We observed multiple factors influencing breeding pair formation by red wolves and found that most wolves paired with similar-sized conspecifics and wolves that formed congeneric pairs with non-wolves (coyotes and hybrids) were mostly female wolves, the smaller of the two sexes. Additionally, we observed tha...