A population of Parides ascanius butterflies was studied for 12 months in Rio de Janeiro, SE Brazil. The population size was approximately 10-20 individuals with a maximum of 50 individuals. Sex ratio was biased, with males dominating in most months. The residence time was 12.7 ± 10.1 days for males, with a maximum of 28 days. Males travel distances of up to 400 m, but most individuals were recaptured within 150 to 250 m of their original capture site. Our results show that P. ascanius has a relatively long adult life span and maintains high population numbers, suggesting that habitat loss rather than population attributes explains its rarity and endangered status.6712934Beirão, M.V., Campos-Neto, F.C., Pimenta, I.A., Freitas, A.V.L., Population biology and natural history of Parides burchellanus (Papilionidae: Papilioninae: Troidini), an endangered Brazilian butterfly (2012) Ann. Entomol. Soc. 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