Habitat manipulation for reestablishment of Utah prairie dogs in Capitol Reef National Park

Utah prairie dogs were transplanted onto the site of a former colony, located in Capitol Reef National Park, Utah. Shrubs on the site were significantly taller than those found on active colonies in similar habitat located on the Awapa Plateau. Therefore, the transplant site afforded a test of the hypothesis that shrub height is a major inhibitory factor affecting occupation of sites by prairie dogs. Four sites of 5 ha each were used. Vegetation treatments — rotobeating, railing, and 2,4 - D herbicide — were carried out on three of the sites and the fourth was used as a control. Shrub height and percent cover were significantly reduced on all three treatment sites. Posttreatment effects on the vegetation showed that the greatest percent moisture of the herbage was found on the railed site, followed by the herbicide, rotobeaten, and control sites. Measurements of the visual obstructions to prairie dogs showed that the rotobeaten site had the greatest visibility, followed by the railed, herbicide, and control sites. Prior to release of prairie dogs on the study area, 200 artificial burrows per treatment were dug, using a power auger. In early summer, 1979, 200 Utah prairie dogs were live - trapped near Loa, Utah. An equal number by sex and age class were released on each treatment. In 1979 a significantly higher number of animals reestablished on the rotobeaten site. In 1980 and 1981 the rotobeaten and railed sites had significantly higher prairie dog numbers than the other sites. Reproduction occurred on both the rotobeaten and railed sites in 1980 and 1981. Results indicated that, when transplanting animals onto sites of former colonies presently overgrown with shrubs, the chances of a successful transplant could be increased by first reducing shrub height and density.     

Chemical and biological characteristics of desert rock pools in intermittent streams of Capitol Reef National Park, Utah

Chemical variability and biological communities of rock pools found in small desert drainage basins of Capitol Reef National Park were characterized over 8 mon in 1994. Neither flooding, drying, nor the presence or absence of surrounding vegetated wetlands had a great effect on chemical composition, which was very dilute and fluctuated somewhat in response to rain events. Neither flooding nor drying affected the composition of biological communities in the pools. Summer storms affected only a few drainages at a time, and only a few study pools of significant volume dried completely during the hot, dry summer. This suggests that only a portion of the Waterpocket Fold aquatic community is ever disturbed at a time, leaving undisturbed areas as a source of recovery. Pools bordered by vegetated wetlands always supported greater numbers of species throughout the year than those bordered only by bedrock, but the same taxa were found in both vegetated and bedrock pools. The rock pool fauna in Capitol Reef National Park appear to be resilient to climatic variability.     

Distribution of shore bugs and shore flies at Sylvan Springs, Yellowstone National Park

Three species of shore bugs (Hemiptera: Saldidae) and 10 species of brine flies (Diptera: Ephydridae) were collected at Sylvan Springs (Wyoming section of Yellowstone National Park, USA), an area containing both acid and alkaline thermal springs. The fauna consists of both widespread (e.g., shore bugs Saldula comatula Parshley and Saldula explanata [Uhler] and shore flies Atissa litoralis [Cole] and Scatella stagnalis [Fallén]) and Yellowstone Park–endemic species (e.g., Saldula nr. arenicola and the shore fly Ephydra thermophila Cresson). The ratio of adults to nymphs of the numerically dominant shore bug Saldula nr. arenicola is higher along heated margins (11–12:1) than along near-ambient-temperature margins (0.6–2:1) of a thermal channel at Sylvan Springs; this may reflect differences in food availability, osmoregularity, thermal tolerance, predation, or other factors. Shore flies include species typical of acid ( E. thermophila ) and alkaline ( Paracoenia bisetosa [Coquillett] and Paracoenia turbida [Curran]) springs.