Citation:

BOYKIN, K., D. F. BRADFORD, AND W. G. KEPNER. HABITAT DISTRIBUTION MODELS FOR 37 VERTEBRATE SPECIES ADDRESSED BY THE MULTI-SPECIES HABITAT CONSERVATION PLAN OF CLARK COUNTY, NEVADA. Presented at National Gap Analysis Conference 2007, Asheville, NC, September 10 - 13, 2007.

Impact/Purpose:

The primary objectives of this research are to:

Develop methodologies so that landscape indicator values generated from different sensors on different dates (but in the same areas) are comparable; differences in metric values result from landscape changes and not differences in the sensors;

Quantify relationships between landscape metrics generated from wall-to-wall spatial data and (1) specific parameters related to water resource conditions in different environmental settings across the US, including but not limited to nutrients, sediment, and benthic communities, and (2) multi-species habitat suitability;

Develop and validate multivariate models based on quantification studies;

Develop GIS/model assessment protocols and tools to characterize risk of nutrient and sediment TMDL exceedence;

Complete an initial draft (potentially web based) of a national landscape condition assessment.

This research directly supports long-term goals established in ORDs multiyear plans related to GPRA Goal 2 (Water) and GPRA Goal 4 (Healthy Communities and Ecosystems), although funding for this task comes from Goal 4. Relative to the GRPA Goal 2 multiyear plan, this research is intended to "provide tools to assess and diagnose impairment in aquatic systems and the sources of associated stressors." Relative to the Goal 4 Multiyear Plan this research is intended to (1) provide states and tribes with an ability to assess the condition of waterbodies in a scientifically defensible and representative way, while allowing for aggregation and assessment of trends at multiple scales, (2) assist Federal, State and Local managers in diagnosing the probable cause and forecasting future conditions in a scientifically defensible manner to protect and restore ecosystems, and (3) provide Federal, State and Local managers with a scientifically defensible way to assess current and future ecological conditions, and probable causes of impairments, and a way to evaluate alternative future management scenarios.

Description:

Thirty-seven species identified in the Clark County Multi-Species Habitat Conservation Plan were

previously modeled through the Southwest Regional Gap Analysis Project. Existing SWReGAP habitat

models and modeling databases were used to facilitate the revision of models. Models were first reduced

to focus areas of the Mojave Desert and Clark County, Nevada, and then a gap analysis was conducted

using the SWReGAP stewardship data to provide tables of representation for the existing models by

intersecting the datasets in a geographical information system (GIS). Tables of representation included

percent and area of predicted habitat within each conservation category. Collaborating with Clark County

personnel, these models were refined for specific application within the two focal areas. Models were

revised based on additional research and included finer scale datasets that were not available at a regional

scale for SWReGAP (e.g. SSURGO). For four focal species, location records were collected and filtered

according to identified criteria for desert iguana (Dipsosaurus dorsalis), common chuckwalla

(Sauromalus ater), phainopepla (Phainopepla nitens), and desert kangaroo rat (Dipsosaurus deserti).

Location data were used in Maximum Entropy modeling to identify habitat associations based on an

inductive modeling framework. Models for all 37 species were revised as necessary and reanalyzed by

intersection of SWReGAP Stewardship datasets to complete a gap analysis and provide tables of

representation of predicted habitat by percent and area within each conservation category. A sensitivity

analysis was conducted using standard methodology and narrative written to explain the dominant factors

in habitat modeling. Deliverables were focused on specific application to the Multi-Species Habitat

Conservation Plan for Clark County, Nevada. Datasets were provided in ERDAS Imagine format at two

scales (240 meter and 30 meter) with corresponding maps of habitat for each species provided in pdf

format.

Record Details: