Mammals of the Grand Mesa, Colorado

The Grand Mesa rises like a green island above the arid Colorado and Gunnison valleys, its cool forests offering a refuge for wildlife. In the mid‑1950s a team of naturalists set out to document the mammals inhabiting this isolated plateau. Their fieldwork revealed twenty‑two species, far more than earlier surveys had suggested, and highlighted several range extensions.

The University of Kansas museum team spent three weeks on the Mesa, trapping and observing mammals across mapped sites. They collected shrews, voles, mice and larger rodents, noting ages, weights and reproductive status. In total twenty‑two species were recorded, including several whose known ranges now extend westward. Field notes added five more species observed but not captured.

Each entry provides measurements, habitat details, and breeding notes, creating a useful reference for ecologists and nature lovers. The study shows how isolated mountain tops act as biodiversity hotspots amid surrounding desert. Listeners will appreciate the careful observation and the sense of discovery that still resonates today.