Bighorn Canyon National Recreation Area Research Articles

Cougar Predation Rates and Prey Composition in the Pryor Mountains of Wyoming and Montana

Abstract Understanding predator-prey dynamics is a fundamental principle of ecology and an ideal component for management decisions. Across North America, the impact of cougars (Puma concolor) on their prey varies regionally. To document the relationships between cougars, bighorn sheep (Ovis canadensis canadensis), mule deer (Odocoileus hemionus), and feral horses (Equus caballus) on the Bighorn Canyon National Recreation Area and the Pryor Mountains, we deployed GPS collars on 6 cougars (the total number residing on the study area), and visited their clusters to determine predation rates and foraging patterns. We examined the composition of cougar kills by species, mule deer sex-age classes, prey size classes, season, and cougar sex. As a measure of selection, we examined the composition of prey killed relative to the composition of ungulates obtained during an aerial survey. We found mule deer were the primary prey, while bighorn sheep constituted secondary prey. While cougars selected for bighorn sheep...

Enigmatic Fossil Footprints from the Sundance Formation (Upper Jurassic) of Bighorn Canyon National Recreation Area, Wyoming

The Sundance Formation (Middle-Upper Jurassic) of Wyoming is well known for pterosaur footprints. Two new partial trackways from the upper Sundance Formation of the Bighorn Canyon National Recreation Area (BICA) of north-central Wyoming are enigmatic. The trackways are preserved in rippled, flaser bedded, glauconitic sand and mud. The deposits were laid down in tidal flats, behind barrier islands, along the mesotidal Sundance Sea. The best-preserved print of the primary trackway possesses four impressions: three shorter digits with negative rotation and an elongate, caudally-oriented mark. The primary trackway has low pace angulation. The combination of morphology and pace angulation matches neither tracks nor body fossils of horseshoe crabs, theropod dinosaurs, pterosaurs, crocodylomorphs, “lacertoids,” or mammaliforms. The secondary trackway, possibly consisting of undertracks, similarly possesses elongate caudal impressions but differs from the former by possessing four subparallel, cranially-oriented digits. These prints also do not closely resemble any of the aforementioned taxa. While the secondary trackway does not lend itself to conclusion, the primary track maker could have been either an injured, pathologic pterosaur or a pterosaurian taxon otherwise unknown from the ichnological record.

Bat and Terrestrial Mammal Inventories in the Greater Yellowstone Network

The National Park Service (NPS) is undertaking a nationwide effort to inventory and monitor the biological resources within its management areas. Recognizing the need for a cross-boundary, ecosystem approach to natural resource management, the system of national parks has been grouped into Cooperative Ecosystem Units to facilitate inventory, monitoring, and subsequent management decisions in ecologically meaningful areas. The Greater Yellowstone Network (GYN) includes Yellowstone and Grand Teton National Parks (YNP and GTNP) and Bighorn Canyon National Recreation Area (BICA). A combined effort of biologists from these parks and regional wildlife experts resulted in the recent release of a study plan for the GYN inventory and monitoring efforts (NPS, 2000). This document identified significant gaps in information on the species richness, abundance, and distribution of bat species within all GYN parks and terrestrial mammals in BICA. They have therefore proposed that the NPS conduct a comprehensive inventory of bats throughout GYN and terrestrial mammals in BICA to establish a benchmark for future monitoring efforts and management actions. The specific goals of these inventory efforts, as stated in the GYN Study Plan (NPS, 2000), are as follows:

Fire History and Potential Fire Behavior in a Rocky Mountain Foothill Landscape

A landscape approach was used to study fire history and fire behavior in the Douglas-fir forests and foothill vegetation of the Bighorn Canyon National Recreation Area in southcentral Montana. The 3,976 ha study area was divided into 4-ha grid cells, and traditional fire scar analysis and fuel sampling methods were used for data collection in each cell. There have been 15 surface fires during the last 109 years and 10 canopy fires during the last 360 years. The mean fire interval in the forests as a whole, was 7 years for surface fires and 31 years for canopy fires. Using the Weibull function, the recurrent time for fire in a specific grid cell was 212 and 226 years for surface and canopy fires, respectively. The distribution of the probability density function showed that there was a peak of high canopy fire frequency between 150-250 years of stand age. There was no obvious peak period for surface fires in humid ravines, which suggests that surface fires there are not associated with aging. Employing Rothermel's model, a fire behavior model (FIREMDL) was developed and linked it to a geographic information system (GRASS) to simulate flammability of each grid cell under different conditions of fuel moisture and wind velocity. The results suggest that flammability is highly variable because of differences in vegetation and topographic position.

Cardiac Telemetry, Natality, and Food Habits of Bighorn Sheep at Bighorn Canyon National Recreation Area

Data were collected from May 1988 to May 1989 to aid in the development of a management program for Rocky Mountain bighorn sheep (Ovis canadensis canadensis) at Bighorn Canyon National Recreation Area (BICA). A principle goal of the management program at BICA is to promote the continued expansion of a reintroduced population of bighorn sheep throughout its ancestral habitat (BICA 1984). In previous research at BICA (Coates and Schemnitz 1988) we identified 3 factors as potentially limiting to herd expansion: visitor and/or vehicular disturbance of bighorns (especially reproductive ewes), competition with horses for a limited supply of grasses, and possible genetic constraints on recruitment (i.e., inbreeding depression) resulting from small founder group size.

Fire History in the Bighorn Canyon National Recreation Area

Work during May included finishing the summarization of data collected in 1988 and preparing for the second field season. Field work for 1989 started on June 4, with graduate student Yegang Wu working in the Bighorn Canyon National Recreation Area (BCNRA)until August 7. Terry Peters provided additional field assistants to work with Yegang on the average of about one day each week from mid-June to early August, a contribution that greatly facilitated data collection.

Cardiac Telemetry, Natality and Genetics of a Recolonized Population of Bighorn Sheep at a Wild Horse Range

Data were collected from 05-88 to 12-88 in continued research to aid in the development of a management program for Rocky Mountain bighorn Sheep (Ovid c. canadensis) at Bighorn Canyon National Recreation Area (BICA). A principle goal of the management program at BICA is to promote the continued expansion of a recolonized population throughout ancestral habitat in the area (BICA 1984). In previous research at BICA (Coates and Schemnitz, 1988), we identified 3 factors as potentially limiting to herd expansion: visitor and (or) vehicular disturbance of bighorns (esp. reproductive ewes), competition with horses for grasses, and possible genetic constraints on recruitment resulting from small founder-group size.

Fire History in the Bighorn Canyon National Recreation Area

Research was initiated in May, 1988, to determine fire history in the coniferous forests and adjacent foothill vegetation located on East Pryor Mountain in the Bighorn Canyon National Recreation Area (BCNRA). The results, anticipated in 1990, will be useful for the development of a fire management plan.

Summary of Research Activities within the National Park Service Areas Cooperating with the U.W.-N.P.S. Research Center, 1987

This section contains a summary of research activities within the National Park Service areas cooperating with the U.W.-N.P.S. Research Center, 1987 including Badlands National Park, Big Hole National Battlefield, Bighorn Canyon National Recreation Area, Bryce Canyon National Park, Arches National Park, Canyonlands National Park, Natural Bridges National Monument, Capitol Reef National Park, Custer Battlefield National Monument, Dinosaur National Park, Fort Laramie National Historic Site, Glacier National Park, Glen Canyon National Recreation Area, Grand Teton National Park, Grant-Kohns Ranch National Historic Site, Jewel Cave National Monument, Knife River Indian Villages National Historic Site, Theodore Roosevelt National Park, Wind Cave National Park, Yellowstone National Park and Zion National Park.

Habitat Utilization, Interspefic Interactions and Status of a Recolonized Population of Bighorn Sheep at a Wild Horse Range

Data have been collected from 05-86 to 11-87 to aid in the development of a management program for Rocky Mountain bighorn sheep (Ovis canadensis canadensis) at Bighorn Canyon National Recreation Area (BICA). The purpose of this report is to summarize progress toward completing the following Objectives: 1. Determine the size, and age/sex composition of the sheep herd at BICA; determine the general health of the herd. 2. Analyze the seasonal food habits of sheep and wild horses; analyze the dietary overlap of these species; analyze the foraging behavior of sheep in habitats occupied exclusively by sheep and compare with the foraging behavior of sheep in habitats used in common with horses and/or humans. 3. Analyze seasonal habitat use throughout the annual cycle; analyze activity patterns during all daylight hours and relate to habitat use; identify and describe sensitive use areas for consideration in future sheep management programs. 4. Determine the total habitat potential of BICA.

Summary of Research Activities within the National Park Service Areas Cooperating with the U.W.-N.P.S. Research Center, 1987.

This section contains a summary of research activities within the National Park Service areas cooperating with the U.S.-N.P.S Research Center, 1987, including Big Hole National Battlefield, Bighorn Canyon National Recreation Area, Bryce Canyon National Park, Canyonlands National Park, Capitol Reef National Park, Custer Battlefield National Monument, Dinosaur National Park, Fort Laramie National Historic Site, Glacier National Park, Glen Canyon National Recreation Area, Grand Teton National Park, Jewel Cave National Monument, Knife River Indian Villages National Historic Site, Theodore Roosevelt National Park, Wind Cave National Park, Yellowstone National Park and Zion National Park.

Abundance and Distribution of Vascular Plants in the Bighorn Canyon National Recreation Area

This study began in 1983 and, as originally proposed, has three phases: 1. Floristic survey and herbarium development (1983-84); 2. Vegetation analysis and classification (1984-85); and 3. Conclusion of vegetation analysis and preparation of a vegetation map (1985-86). Justification for the study was to provide the Bighorn Canyon National Recreation Area (BCNRA) with basic vegetation information that could be helpful in resource management. Very little ecological research had been done in the BCNRA.

SUMMARY OF RESEARCH ACTIVITIES WITHIN THE NATIONAL PARK SERVICE AREAS COOPERATING WITH THE U.W.-N.P.S. RESEARCH CENTER, 1986.

This section contains a summary of research activities within the National Park Service areas cooperating with the U.W.-N.P.S. Research Center in 1986, including Bighorn Canyon National Recreation Area, Canyonlands National Park, Capitol Reef National Park, Custer Battlefield National Monument, Dinosaur National Monument, Fort Laramie National Historic Site, Glacier National Park, Glen Canyon National Recreation Area, Grand Teton National Park, Jewel Cave National Monument, Knife River Indian Villages National Historic Site, Theodore Roosevelt National Park, Wind Cave National Park, Yellowstone National Park and Zion National Park.

Fish, Amphibian, and Reptile Inventory for the Bighorn Canyon National Recreation Area

This study was designed to inventory fish, amphibian, and reptile populations inhabiting the Bighorn Canyon National Recreation Area using standard sampling techniques and field observations in order to determine species composition, distribution, relative abundance, and habitat associations.

Abundance and Distribution of Vascular Plants in the Bighorn Canyon National Recreation Area

This study began in 1983 and, as originally proposed, has three phases: 1. Floristic survey and herbarium development (1983-84); 2. Vegetation analysis and classification (1984-85); and 3. Conclusion of vegetation analysis and preparation of a vegetation map (1985-86). This work is on schedu1e. Justification for the study was to provide the Bighorn Canyon National Recreation Area (BCNRA) with basic vegetation information that could be helpful in resource management. Very little ecological research has been conducted in the BCNRA.

Summary of Research Activities within the National Park Service Areas Cooperating with the U.W.-N.P.S. Research Center, 1985

This section contains a summary of Research Activities within the National Park Service areas cooperating with the U.W.-N.P.S. Research Center in 1985, including Bighorn Canyon National Recreation Area, Canyonlands National Park, Capitol Reef National Park, Custer Battlefield National Monument, Devils Tower National Monument, Dinosaur National Monument, Fort Laramie National Historic Site, Glacier National Park, Glen Canyon National Recreation Area, Golden Spike National Historic Site, Grand Teton National Park, Jewel Cave National Monument, Knife River Indian Villages National Historic Site, Theodore Roosevelt National Park, Wine Cave National Park, Yellowstone National Park and Zion National Park.

Vertebrate Inventory for Bighorn Canyon National Recreation Area

The study is designed to inventory vertebrates in Bighorn Canyon National Recreation Area using standardized censusing techniques and field observation. Locations, numbers, status, and habitat associations will be determined.

Abundance and Distribution of Vascular Plants in the Bighorn Canyon National Recreation Area

This study began in 1983 and, as originally proposed, has three phases: 1) Floristic survey and herbarium development (1983-84); 2) Vegetation analysis and classification (1984-85); and 3) Conclusion of vegetation analysis and preparation of a vegetation map (1985-86). This work is on schedule. Justification for the study was to provide the Bighorn Canyon National Recreation Area (BCNRA) with basic vegetation information that could be helpful in resource management. Very little ecological research has been conducted in the BCNRA.

Abundance and Distribution of Vascular Plants in the Bighorn Canyon National Recreation Area

The objective of this study is to conduct a floristic survey and a vegetation analysis of the Bighorn Canyon National Recreation Area (BCNRA) located in the northern part of the Bighorn Basin of northern Wyoming and southern Montana. The study will include the preparation of a vegetation map which, along with other ecological information, should be useful for resource management.

Evaluation of Water Quality and Rate of Sedimentation of Bighorn Lake

The managers of the Bighorn Canyon National Recreation Area have expressed concern about two aspects of water quality in Bighorn Lake, the rate of sediment accumulation in the upper ends of the lake, especially in the Horseshoe Bend region, and the excessive fertility that occurs generally in the upper end, although it sometimes extends throughout the total length of the lake. In the spring of 1980 a cooperative study was initiated which was designed to estimate the rate of sediment accumulation in the Horseshoe Bend area of Bighorn Lake since closure of the Yellowtail Dam in 1967. Studies were also initiated to evaluate the sources of aquatic plant nutrients, the factors limiting phytoplankton growth within the upper ends of Bighorn Lake, and the current degree of eutrophication-fertility of waters in this region of the waterbody. This report presents a summary of the results of the first eight months of these studies.