Primary purpose
To provide a qualitative assessment of wildlife habitat for use in (a) evaluating impacts from water development projects, (b) establishing base line data prior to habitat changes, (c) comparing candidate area for land acquisition or mitigation, and (d) evaluating habitat quality and wildlife management potential.
Applicable habitat types
Upland, bottomland, and wetland habitat in Texas.
Expertise needed
Experienced biologist and ability to identify dominant plants.
Categories assessed
Three categories are addressed: biological habitat components, protected and endangered species, and acquisition and administration.
Procedure
The user(s) visits representative sites of each cover type within a study area and completes the biological habitat data sheets that (a) identify the evaluation components, (b) list criteria for each component, and (c) assign points (e.g., 1-25) to criteria. All points are summed, divided by the number of sites to obtain an average, and then multiplied by 1/100 to obtain an average habitat quality score. Habitat units are calculated for each cover type and totalled for the entire study area. The user(s) evaluates the entire study area for the other categories using similar data sheets. Results are reported as the protected species or endangered species score and the acquisition and administration components score.
Key Terminology
Acquisition and administration components score: a score where 1.0 indicates that the tract of land has the highest acquisition priority; a score of 0 indicates no priority.
Average annual habitat unit (AAHU): the total number of HUs gained or lost as a result of a proposed action, divided by the life of the action.
Average habitat quality score: unitless number bounded by 0 and 1 where 0 represents no habitat quality and 1 represents optimum habitat.
Habitat unit (HU): a value derived from multiplying the average habitat quality score for a cover type by the size of the areas for which this score was calculated (HU = average habitat quality score x size of cover type).
Protected species or endangered species score: the total number of points assigned for the occurrence of endangered, threatened, and/or protected nongame species.
Output
Measures of habitat quality, significance of protected species, and acquisition priority of a site.
Estimated time to assess 1 acre site
Total 8 hours per study area.
8 hours: Obtain or produce vegetation cover map (step 1), determine minimum number of sites (step 2), and apply evaluation keys for "Biological Habitat" to each site within each cover type (step 3).
Comparison of habitat types
Can directly compare habitats (wetland, bottomland riparian zones, and upland) within Texas.
Use as guide to design
Individual variables (components) may provide useful design information, but WHAP does not provide validated threshold values for many of these variables. Users can refer to the variables to determine which conditions increase or decrease habitat quality. Individual component values can be used to determine habitat improvement and vegetation management direction. This can be translated into design criteria with explicit measurements (e.g., design wetland as seasonally flooded with mixed bottomland hardwoods; 15 or more woody species). Some variables may not be useful. For example, variables that measure the presence of fauna (e.g., occurrence of endangered species) cannot be incorporated into the design because fauna cannot be controlled. Finally, the design criteria for some variables may be unsuitable and the overall rating of function may be misleading for the reasons given above.
Contact person
Roy Frye, Texas Parks & Wildlife Department, 4200 Smith School Rd., Austin, TX 78744 phone: (512) 389-4579; fax: (512) 389-8059; e-mail: roy.frye@tpwd.state.tx.us
Related procedures
None.
Extent of use/field testing
WHAP has been extensively field tested and used on a number of large and small projects statewide in Texas. Over the last two years, WHAP has been used four times by the Texas Parks and Wildlife Habitat Assessment Program (e.g., reservoirs, highway projects, pipelines, and transmission lines).
Proposed future revisions
Planned for 1999, with only minor revisions.
Key Reference
Frye, R. 1995. Wildlife Habitat Appraisal Procedure (WHAP). Texas Parks and Wildlife Department, Austin, TX.