SWReGAP Wildlife Habitat Relations=
hip Reports
&nbs= p; The Southwest Regional Gap Analysis Project (SWReGAP) wil= dlife habitat relationship reports delineate the various attributes incorporated to produce predictive distributions for over 800 terrestrial and avian species= . The following paragraphs provide ex= planations for each section of the report.
&nbs= p; The Integrated Taxonomic Information System (ITIS) was formed through a partner= ship of several agencies, including the United States Geological Survey, the Environmental Protection Agency and the National Museum of Natural History,= in an effort to standardize taxonomic classification. For more information about ITIS, vi= sit <http://www.itis.usda.gov/>. <= /span>The ITIS code is a unique number assigned to each known species. The SWReGAP species use the ITIS classification codes, except where recent literature necessitated a change = in taxonomic rank, and thus classification code. Those species were then assigned an arbitrary identification number instead of the ITIS code.
&nbs= p; The model description section indicates when the habitat model is seasonal. The model is assumed to be year-round unless otherwise stated. This section also denotes which attributes should be weighted, if applicable. “Final SWReGAP model= 221; should appear in this section for all completed models.
&nbs= p; The background section provides a general description of each species’ habitat requirements and range within the Southwest. It is the foundation for the attrib= utes selected to be used in the modeling process. The background also includes any information about the species that is important for users to consider, but = cannot be incorporated into the actual model.
&nbs= p; The description changes section specifies any modifications that were performed each time the model was edited. Information that did not fit in the model description above due to space limitations is= placed in this section.
&nbs= p; Weighted overlay only appears on the report if one or more attributes are more impor= tant to a species than others and need to be weighted accordingly.
&nbs= p; The relationships section lists all of the modeled attributes. Most of the relationship attribute= s are self-explanatory. Distance to= water indicates what types of waterbodies the species= is affiliated with and also how far from water the species may travel. If one or more soil types were sele= cted, any watershed in which that soil type occurs will be selected.
&nbs= p; The modeling process for the wildlife habitat relationships utilized a Boolean approach. Generally, “AND” statements were used to link the attributes, resulting in suitable habitat being predicted where all the required attributes occurred together. Using the “AND” statement when modeling the hydrology attributes causes t= he predicted distribution to appear only within the specified distance to wate= r, which is used for species that are strongly associated with water. Species that are not dependent on w= ater and can be found in riparian and non-riparian areas were modeled with an “OR” statement linking hydrology and land cover when hydrology attributes were selected. The= ir predicted distributions included the area within the specified distance to water as well as selected land cover outside of this specified distance.