By Dave Lovell, Habitat Biologist, Colorado Division of Wildlife

The Colorado Division of Wildlife (DOW) has just launched the Colorado Riparian Mapping Web Page <> as part of the Natural Diversity Information Source (NDIS) web site. The Riparian web page highlights the Division’s Colorado Riparian Vegetation Mapping Project. The Riparian Mapping Project is funded primarily by Great Outdoors Colorado but has received support from other Federal and State agencies, and private non-profit groups as well. The Riparian Mapping Project is one of the many components of the overall NDIS effort being undertaken by the Division of Wildlife through its Habitat Section. The goal of the Riparian Mapping Project, to the extent practical, is to develop a statewide data layer of riparian vegetation that is available for use in natural resource planning applications.
The Colorado Riparian Mapping Project began initially as a cooperative project between the Division of Wildlife and the U.S. Forest Service. The Pike/San Isabel National Forest was interested in mapping riparian vegetation on lands they administered and had the funding but no GIS mapping capability. The DOW had the GIS mapping capability but didn’t have the hard cash to contribute to mapping. As a result, the two agencies partnered and between 1990 and 1996 mapped the riparian vegetation on the Pike and San Isabel National Forest, and the Comanche and Cimmaron National Grasslands. Since that time, partnerships with the Bureau of Land Management, USGS-Biological Resources Division, Department of Natural Resources, Colorado Natural Heritage Program, and several private non-profit groups has resulted in additional areas being mapped.
Sample Riparian Map
The Colorado Riparian Mapping Project produces highly detailed vegetation maps using infrared aerial photographs and photo-interpretive techniques. The photos are obtained in stereo so that the photo-interpreter sees a 3-dimensional image and can discern differences in vegetation based both on structure (height and canopy type) and color. The mapping is done at a scale of 1:24,000 on USGS topographic quads with delineation based both on vegetation and the geomorphology of the channel. The minimum mapping unit is ½ acre although polygons as small as 1/10 acre have been delineated by the photo-interpreter. Channels less than 80′ wide are mapped as a line feature. Delineation is performed on stable based mylar that is geo-referenced to the stereo photography and to mylar topographic quads using multiple ground control points. The hard copy product (figure at right) is then scanned, edited, and attributed using a line tracer software program (LTPlus or ArcScan). CDOW Wildlife Resource Information System (WRIS) Biologists complete final processing into an ArcInfo Geographic Information System (GIS) mapping program.
The primary purpose of the Riparian Web Page is to make the data more broadly available to folks both within and outside the Division of Wildlife for use in natural resource planning, habitat assessment, and resource protection. The web site provides background and explanatory information on the mapping project, and an FTP site where data can be obtained. Anyone with GIS mapping software (ArcInfo, ArcView, IDRISI, AutoCad, etc.) can utilize the data.
Development of the Riparian Web Page was the result of over 9 months effort and further enhances the overall value of the NDIS web site which has been designed to make wildlife resource data available to a broad spectrum of interested publics for natural resource planning purposes. The Colorado Riparian Vegetation Project currently has approximately 250 topographic quads of mapped data on the FTP site, 150 quads where mapping is in progress, and another 60 quads planned for mapping this year. The mapping effort has been undertaken in a variety of locations across the state. For example, a large block of Front Range Quads have been completed and data will soon be complete and available for both the South Platte and Arkansas Rivers from their headwaters to the State line. A status map (Figure 2) displaying topographic quads completed and those “in progress” is also part of the web site.
The riparian data has multiple uses and applications for natural resource planning. The original purpose of the cooperative mapping effort between the CDOW and USFS was to incorporate the mapped riparian data into their Forest Plan and thereby designate riparian areas as a “No Surface Occupancy” feature. The riparian data on the Upper Arkansas River was used in conjunction with the Arkansas River Water Needs Assessment undertaken by several agencies including CDOW, BLM, Bureau of Reclamation, and Division of Parks and Outdoor Recreation to ascertain the potential effect of increased or reduced flows in the upper Arkansas River on riparian/wetland vegetative communities. The riparian data was also recently used to develop a habitat suitability model for the Preble’s Meadow Jumping Mouse, a Federal Threatened species. The riparian data was combined with an occurrence database and through the use of logistic regression techniques a habitat suitability model was developed. The model indicated that the presence of Preble’s was strongly associated with the presence of riparian shrub and with distance to riparian shrub. This model has been used in a predictive fashion to prioritize survey efforts and for protection of habitat through the various Section 7 and Habitat Conservation Planning processes being undertaken along the Front Range. As individual topographic quads are mapped and larger more complete blocks of riparian data developed the data has also been used for county land use planning purposes in the designation of Significant Wildlife Habitat. Riparian habitat represents only about 5% of the landmass in Colorado but supports upwards of 75% – 80% of the wildlife species. Riparian areas are also highly susceptible to development pressure. For these reasons it is important that riparian areas receive special consideration through the development review process.
The Colorado Riparian Vegetation Mapping Project is the result of a strong effort and support by CDOW WRIS Biologists Pam Schnurr, Francie Pusateri, and Seth McClean along with several Natural Resource Ecology Lab (NREL) employees including Scott Strain, Tammy Wilson, and Dawn Brownne. These folks along with myself as Riparian Coordinator are responsible for organizing and coordinating various mapping projects within their respective regions and for preparing the data for posting on the FTP site.
The primary funding for the Colorado Riparian Vegetation Mapping Project is received from Great Outdoors Colorado. Those funds support the mapping of approximately 60 Quads per year. With only about 25 percent of the 1800 Quads covering Colorado completed this represents a rather daunting task. The Colorado Riparian Vegetation Mapping Project is also highly dependent on supplemental funding through cooperative projects with other Federal, State, and Local government, and Private Non-Profit entities. It currently costs between $1,600 – $1,800 to completely map one USGS Topographic Quad, however that represents a cost of only $0.05 per acre. This includes the cost of purchasing the infrared photos, delineation, and digital processing.

Riparian Coordinator:
Dave Lovell – Habitat Biologist Colorado Division of Wildlife 2126 N Weber Street Colorado Springs, CO 80907 (719) 227-5227
West Region:
Colorado Division of Wildlife
Pam Schnurr – WRIS Biologist
711 Independent Ave
Grand Junction, CO 81505
(970) 255-6180
Southeast Region:
Seth McClean – WRIS Biologist
Colorado Division of Wildlife
2126 N Weber Street
Colorado Springs, CO 80907
(719) 227-5286
Northeast Region:
Francie Pusateri – WRIS Biologist Colorado Division of Wildlife
317 W Prospect Street
Fort Collins, CO 80526
(970) 472-4336

Anyone wishing to participate in this ongoing endeavor is encouraged to contact either their respective Regional WRIS Biologist or myself. The Colorado Riparian Vegetation Mapping Project should continue to flourish and additional data developed and added to the Riparian Web Page through their efforts and with the continued financial support of Great Outdoors Colorado and other interested cooperators.

Status Map
Click on Image for enlarged version
(95K bytes)

Colorado Riparian Association