Black flies have been long-time residents of Maine and cause extensive nuisance problems for people, domestic animals, and wildlife. The black fly problem has no simple solution because of the multitude of species present, the diverse and ecologically sensitive habitats in which they are found, and the problems inherent in measuring the extent of the damage they cause. To improve the understanding of the nature of the black fly problem, an inventory of black fly species and habitats was made throughout the state. Previous black fly surveys in Maine have been geographically limited. In the present survey, black flies were collected extensively throughout the state from 1976 through 1978. Presented here is an annotated list of species found, records of black fly species swarming around humans or biting humans, and the succession of species in selected streams and rivers.https://digitalcommons.library.umaine.edu/aes_techbulletin/1102/thumbnail.jp