Additional Records and Extensions of Known Ranges of Mammals from Utah — Background and Themes

New State Records and Range Extensions

The authors report two mammals not previously known to occur in Utah: the dusky shrew (Sorex vagrans obscurus) and the water shrew (Sorex palustris navigator). For the dusky shrew, twelve specimens from the Abajo Mountains and Elk Ridge extend the known range approximately 80 miles southward. The water shrew is recorded from a single sight observation at North Creek, seven miles west of Monticello, at 8,000 feet elevation. The authors explicitly note their usual reluctance to rely on sight records but justify this exception because the species is "so distinctive that it can be readily recognized." Other significant range extensions include the Yuma myotis, previously thought restricted to southwestern Utah, now identified from a specimen in Uintah County after a re-examination of earlier identifications. The gray fox skull from the Deep Creek Mountains extends the known range 150 miles northward in Utah, while the river otter, rare in the semi-arid state, is documented from two complete specimens trapped in Boxelder County.

Specimen-Based Evidence and Cautious Inference

The authors consistently ground their claims in physical specimens, providing catalog numbers, precise localities, and often the names of collectors or donors. For example, the moose record relies on a skull from Weber College and an antler from the University of Utah, both from young bulls, supplemented by sight reports from state game department employees. The mountain sheep record is based on a two-year-old ram killed by a deer hunter in the La Sal Mountains, which constitutes the first complete specimen (skin and skull) of a mountain sheep from Utah. The authors note that this ram was running with a herd of mule deer and was the only mountain sheep seen. Such details reveal the opportunistic nature of specimen collection and the reliance on incidental encounters. The text also acknowledges gaps: for instance, no gray fox has been obtained from mountains within the basin of ancient Lake Bonneville, even though they occur in nearby ranges.

Structure as a Supplement to a Prior Work

The paper is explicitly framed as a supplement to Durrant (1952), and its structure reflects that purpose. Each species account begins with the scientific name and common name, followed by a summary of previous knowledge, then the new records with locality data, and finally the significance of the extension. The authors frequently cite the earlier work and other regional studies, such as Hall's Mammals of Nevada and Davis's Recent Mammals of Idaho. The literature cited section includes foundational references for Utah and neighboring states. This format allows readers to update their understanding of mammal distributions without re-reading the entire 1952 monograph. The paper also demonstrates the cumulative nature of natural history knowledge, as each new specimen can shift the known boundaries of a species' range.

Readers interested in the historical development of mammalogy in the Intermountain West will find this supplement a concise example of how specimen-based research refines species distributions. The authors' careful documentation of localities, elevations, and specimen numbers provides a model for scientific reporting. For those using this text alongside Durrant's 1952 monograph, the new records and range extensions offer a snapshot of ongoing fieldwork and collaboration between universities and state agencies.

Over the years, I've noticed how a careful list of mammal ranges, like that 1955 Utah supplement, holds the same quiet patience as a field guide. Both trust the slow work of watching, of noting where creatures truly live. That old data feels like a whispered secret, and it finds a warm sibling in the pages of Wild Animals of Yellowstone National Park — Reading Companion, whispering of place and presence.