ABS 2022
Infanticide and inbreeding: tradeoffs in female mate choice in the face of allied sexual coercion
Molly H.F. McEntee1, Vivienne Foroughirad1, Ewa Krzyszczyk2, Alexis L. Levengood3, Eric M. Patterson4, Megan M. Wallen5, CÚline Frѐre6, Janet Mann1. 1Georgetown University, Washington, District of Columbia, United States; 2Bangor University, Bangor, , Wales; 3University of the Sunshine Coast, Sippy Downs, Queensland, Australia; 4National Oceanic and Atmospheric Administration, Silver Spring, Maryland, United States; 5National Oceanic and Atmospheric Administration, Seattle, Washington, United States; 6University of Queensland, Brisbane, Queensland, Australia

In sexually coercive mating systems, males use aggression to induce females to mate. The degree to which coercive strategies prevent female mate choice, however, is debated. Male Indo-Pacific bottlenose dolphins (Tursiops aduncus) form long-term alliances that harass and mate guard females. Females invest substantially in each offspring; gestation lasts one year and lactation lasts three to eight years. Consequently, females could be under strong selection pressure to maximize the genetic fitness of each offspring via mate choice. We integrate 35+ years of behavioral and genetic data on Indo-Pacific bottlenose dolphins in Shark Bay, Australia, to investigate the role of female mate choice within a coercive mating system. Results from a GLM (N = 70 paternities) suggest that male age, home range overlap, and previous social association, butánot relatedness to the female impact the likelihood of paternity. Middle-aged (age 20 - 35) males who are local to and socially associated with a female are more likely to sire her offspring. While females plausibly benefit by mating with local, socially associated males to reduce infanticide risk, this could also increase the risk inbreeding.