The identification of habitat networks (or linkages) can be accomplished using current high resolution aerial photo coverage combined with available GIS databases (topography, natural heritage data, land use, etc) as available. Delineation of the terrestrial and aquatic habitat networks consists of delineating linked habitats, or patches, distributed along and among definable natural corridors. The linkages may be physical and/or could be linked based on a species’ use of the habitat. An example of a physical linkage is a stream and its associated forested riparian corridor. On the other hand, neo-tropical migrant bird species may use physically separated habitat (e.g. mature forest patches made up of certain species/age composition). Species movement between and use of separate patches creates the connectivity or network. Information obtained in Step 1, such as Critical Habitats, protected lands and heritage database locations, should be utilized to develop the habitat network map for the landscape study area. Patch refinement is discussed further in Step 6.0. Incorporating knowledge of potential target species and their use of habitats in the study area can be used at this stage to initially define networks for these species.
The habitat network map is a very useful figure and can be used in agency meetings. Some states are developing habitat (patch/corridor) network or “linkages” mapping as part of a State Wildlife Action Plan (SWAP) or similar plans and should be referenced or adopted as appropriate. Resources that provide additional information useful to define habitat networks include: