This dataset represents areas of high habitat heterogeneity within the Re-evaluating Florida's Ecological Conservation Priorities in the Face of Sea Level Rise project study area. Features in this dataset are those portions of the project study area where more than 6 unique natural land cover classes exist within a 25 hectare window. These features were identified through a focal statistics raster analysis of the FL_LandCoverCoastal_FNAI dataset within a coastal analysis zone defined as areas in Florida of equal to or less than 3 meters elevation plus a 1 kilometer buffer. The features in this dataset are considered "sources" because they contain areas of less than 1 meter and do not intersect areas of equal to or greater than 3 meters. Because of their high habitat heterogeneity and low elevation, these areas may be sources of species migrating inland to escape sea level rise.This dataset complements FL_HabHetRefuges_FNAI.