Inventories

Background

Natural resource inventories are extensive, point-in-time efforts to determine the location or condition of resources, including the presence, class, distribution, and status of plants, animals, and abiotic components such as water, soils, landforms, and climate.

The primary purpose of the inventory phase of the I&M program is to assess and document the current condition and knowledge of natural resources in the parks. Combining existing data and current research, and comparing the existing conditions to the natural or desired state of the parks provides a solid baseline for management and long-term monitoring. These projects have also facilitated the exchange of ideas and information among parks of the Sonoran Desert.

National and network field studies and data collection are being conducted on plants, animals, water, soils, geology, climate, and other resources as part of a broader National Park Service initiative to complete basic resource inventories in all national parks with significant natural resources.

In its network parks, the SODN has inventoried biological, climate-related, geologic, and paleontologic resources, as well as invasive exotic plants, and has conducted vegetation mapping.

Natural resource inventory objectives

1. Compile historical data, from a variety of sources, for all species of vascular plants and vertebrates believed to occur in Sonoran Desert Network parks, including museum records of voucher specimens, previous studies, and park databases, and input these data into the appropriate NPS databases.

2. Document, through field investigations, at least 90% of all species of vascular plants and vertebrates estimated to occur in each park.

3. Gather inventory information using a random, repeatable design so that species richness for each taxonomic group in each park can be estimated with a specified level of confidence for use in long-term monitoring of species richness.

4. Develop GIS-based distribution maps for each species in each network park.

5. Conduct inventories of particular species of special concern and provide park managers with detailed maps of their distribution and, where possible, estimates of abundance.