To the MARMAM community: We are pleased to share our new article, which was recently published in Behavioural Processes: Ham, J.R., Lilley, M.K., Lelekach, J., Miller, M.R., Robeck, T.R., Pellis, S.M., & Manitzas Hill, H.M. (2022). The emergence and early development of socio-sexual behavior in beluga calves (Delphinapterus leucas). Behavioural Processes, 200, 104695. https://doi.org/10.1016/j.beproc.2022.104695 Abstract: While the ontogeny of beluga (Delphinapterus leucas) socio-sexual behavior has been documented in animals between 37- and 108-months-old, the first 36 months of life are yet to be examined. This study investigated how socio-sexual behaviors emerge over the first three years of life in a group of belugas in managed care. The emergence of socio-sexual behaviors was relatively consistent among immature animals. More complex behaviors, like s-posture presentations, developed in a piecemeal fashion (i.e., simple components of the behavior sequence emerged before complex components). The presence of an adult male significantly predicted if immature belugas would initiate and participate in socio-sexual behavior. However, partner preferences changed with age. In the first year of life, belugas engaged in sexual behavior with their mother most frequently but preferred to play with older males if given a choice. By the third year of life, belugas engaged in socio-sexual behavior most frequently with other immature animals. These findings enhance our understanding of how belugas develop sexually and socially and have implications for social housing practices of immature belugas. Please do not hesitate to email us if you have any questions. Best, Jackson & co-authors Jackson R. Ham, M.Sc. Ph.D. Student Canadian Centre for Behavioural Neuroscience Department of Neuroscience University of Lethbridge jackson.r.ham@gmail.com