Appleby, DanielTripovich, Joy S.Langmore, NaomiHeinsohn, RobertPitcher, BenCrates, Ross2026-02-202026-02-200006-3207https://hdl.handle.net/1885/733805702Understanding the factors affecting the success of animal reintroductions is crucial for facilitating endangered species recovery. Cultural differences between individuals from different animal populations can lead to assortative mating, whereby individuals prefer to breed within their own familiar cultural cohort. Assortative mating can hinder the assimilation of zoo-bred individuals into wild populations, so quantifying this risk becomes important for informing adaptive management strategies in conservation. We conducted mate choice experiments on zoo-bred female regent honeyeaters (Anthochaera phrygia) to assess whether they showed stronger behavioural responses to the familiar but abnormal songs of zoo-bred male regent honeyeaters than those of their wild counterparts or an interspecific control song. Female regent honeyeaters were no more likely to enter the playback aviary in response to the songs of zoo-bred males than those of wild males or a different species. However, females that did enter the playback aviary were significantly more likely to respond quickly, approach the speaker closely and remain in the playback aviary for longer in response to the songs of zoo-bred males than wild songs or control songs. Our study is the first to show experimentally that zoo-bred females prefer familiar, but abnormal, zoo-bred songs over unfamiliar wild-type songs. We suggest that assortative mating amongst released birds is a risk in reintroduced regent honeyeaters, given recent evidence that the breeding success of reintroduced pairs is low. Our study demonstrates how small-scale experiments conducted within applied zoo-breeding settings can yield useful information to refine husbandry techniques and reduce cultural divides between wild and reintroduced populations.DA received funding from Holsworth Wildlife Research Endowment 2021, and the Cumberland Bird Observers Club. JT and BP received funding from Winifred Violet Scott Charitable Trust. Regent Honeyeater research at Taronga Conservation Society is supported by the Commonwealth of Australia Department of Climate Change, Energy, the Environment and Water grant “Expansion and Capacity Building in Recovery of Critically Endangered Regent Honeyeater and Bellinger River Snapping Turtle (ERF-WRR2-017-018).application/pdfen-AU© 2023 The Authorshttp://creativecommons.org/licenses/bync- nd/4.0/202310.1016/j.biocon.2023.1101712023-10-01CC BY-NC-ND license