Managing escalating human impacts on nearshore cetaceans requires information on a species' demography and distribution patterns at appropriate spatial scales. Identification photographs of individuals of a population of inshore Indo-Pacific bottlenose dolphins, Tursiops aduncus, were obtained in the open coastal waters off North Stradbroke Island, Australia and used to estimate population density and residency. Five hundred and eighty-one individuals were identified from 342 school sightings during 1998 and 1999. Mark-recapture analysis using closed population models estimated a population size of between 700 and 1,000 individuals within the study area during winter, with evidence that the population contained resident individuals. This represents an extremely high number of dolphins within a small area, which requires a pre-emptive management strategy to ensure their continued occupancy.