The Miami blue butterfly Cyclargus thomasi bethunebakeri (Lepidoptera: Lycaenidae) has been listed by the state of Florida as an endangered species since 2003. This once common butterfly previously occurred in 16 coastal Florida counties but is now limited to a single remaining location in the lower Florida Keys within the boundaries of Bahia Honda State Park. Field studies have shown that the butterflies exist as a metapopulation, with 13 subpopulations occurring on Bahia Honda. Individual subpopulations may disappear and reappear over time and preliminary data show a population range of 20-115 adult butterflies. Studies have also demonstrated that these are highly sedentary butterflies with poor dispersal abilities and a short winter diapause. Females live significantly longer than males in the field (4.3 days versus 2.2 days) but there is a highly equal sex ratio with both sexes emerging similarly over the same time period. A captive colony of Miami blue butterflies has been produced from Bahia Honda nucleus stock to safeguard the remaining population and to recolonize appropriate areas within two south Florida national parks. Our preliminary mark-release-recapture data, new knowledge of life history traits, and information of metapopulation dynamics from Bahia Honda are currently used in the development of comprehensive reintroduction, conservation and management strategies for this species.