Valles Caldera National Preserve (VALL) encompasses 35,977 ha (88,900 ac) in the Jemez Mountains of north-central New Mexico and is surrounded by the Santa Fe National Forest, the Pueblo of Santa Clara, and Bandelier National Monument. VALL’s explosive volcanic origin, about 1.23 million years ago, formed the Valles Caldera—a broad, 19- to 24-km (12- to 15-mi) wide circular depression. It is one of the world’s best examples of a young caldera (in geologic time) and serves as the model for understanding caldera resurgence worldwide. A series of resurgent eruptions and magmatic intrusive events followed the original explosion, creating numerous volcanic domes in present day VALL—one of which is Redondo Peak at an elevation of 3,430 m (11,254 ft), which is the second highest peak in the Jemez Mountains. In fact, VALL in its entirety is a high-elevation preserve that hosts a rich assemblage of vegetation, wildlife, and volcanic resources. The National Park Service (NPS) Natural Resource Condition Assessment (NRCA) Program selected VALL to pilot its new NRCA project series. VALL managers and the NRCA Program selected seven focal study resources for condition evaluation. To help us understand what is causing change in resource conditions, we selected a subset of drivers and stressors known or suspected of influencing the preserve’s resources. What is causing change in resource conditions? Mean temperatures during the spring and summer months are increasing, but warming is slower at VALL than for neighboring areas (e.g., Bandelier National Monument). The proportion of precipitation received as snow has declined. From 2000 to 2018, forest pests damaged or killed 75% of the preserve’s forested areas. Only small, forested areas in VALL were affected by forest pests after the 2011 Las Conchas and the 2013 Thompson Ridge fires. The all-sky light pollution model and the sound pressure level model predict the lowest degree of impacts from light and sound to be in the western half of the preserve.

Capitol Reef National Park (CARE) encompasses approximately 381 mi2 (98,711 ha) in southcentral Utah, and over 70% is managed for its rugged and remote wilderness value. It’s known for its spectacular display of geologic features, including the Waterpocket Fold—an extensive, upthrusted sandstone geologic feature that is the longest exposed monocline in North America. CARE contains high plant diversity and has a large concentration of locally rare and endemic plants, representing about 18% of the park’s total number of plant species. The Fremont River, perennial creeks, and springs, seeps, and tinajas are valued sources of water in the high desert environment of the Colorado Plateau, providing critical habitat for migrating and breeding birds, invertebrates, and other wildlife. At least 58 mammals, including desert bighorn sheep (Ovis canadensis nelsoni), have been confirmed at the park, and three native fishes are species of special conservation status in Utah. The National Park Service Natural Resource Condition Assessment Program (NRCA) selected CARE to pilot its new NRCA project series. These projects evaluate the best available science to provide park managers with reliable, actionable natural resource condition information. CARE managers selected 11 focal study resources for their NRCA. To help us understand what is causing change in resource conditions, we selected a subset of drivers and stressors known or suspected of influencing the park’s focal resources.

Glen Canyon National Recreation Area (GLCA) encompasses more than 0.5 million ha (1.25 million ac) and extends over 322 km (200 mi) from its northern boundary in southern Utah to its southern boundary in northern Arizona. It is one of the most rugged, remote, and floristically diverse national parks on the Southern Colorado Plateau (Thomas et. al 2005) and has more than 4,900 km (3,045 mi) of waterways flowing through its eight Hydrologic Unit Code (HUC 8) watersheds. GLCA’s larger perennial rivers include the Colorado, Escalante, Dirty Devil, San Juan, and Paria, with smaller perennial and intermittent streams flowing into each of these rivers. After the creation of the Glen Canyon Dam, Lake Powell formed, covering 13% of the park’s total land area when full and the national recreation area attracts over 4 million visitors annually, and in 2019 GLCA ranked 19th highest in recreational visits out of all national parks. The National Park Service Natural Resource Condition Assessment Program selected GLCA to pilot its new NRCA project series. NRCA projects evaluate the best available science to provide park managers with reliable, actionable information pertaining to natural resource conditions in their park. For the park-selected focal study resources, this includes consideration of drivers and stressors known or suspected of influencing resource conditions; assessment of current conditions and trends for indicators of condition; and potential near-term and future activities or actions managers can consider, improving their knowledge and management of natural resources in parks. For focal resources that lack adequate data to assess current conditions, a gap analysis is provided (in lieu of a condition assessment) to highlight the present status of knowledge of the resource and to suggest useful indicators, data, and studies for further consideration and investigation. Park managers are encouraged to identify information needs and pose questions during the NRCA scoping process, with the understanding that information will be provided to help address those needs and answer those questions when possible. For a comprehensive list of GLCA managers’ questions and needs, please refer to Appendix A, Table A-1. The focus of GLCA’s NRCA study was the water-dependent resources—tinajas, springs & seeps, including water quality, riparian zone, amphibians, including the northern leopard frog (Lithobates pipiens), and small, native fishes—that are found off the mainstem Colorado River. Managers were interested in these particular environments and the natural resources that depend on them because they are less studied, and the habitats are “biodiversity hotspots” due to the intersection of complex desert and freshwater ecosystems in a region limited by water. The following summaries highlight the key findings of GLCA’s focal resource drivers and stressors (Chapter 2), states (Chapter 3), and manager responses (Chapter 4).