The mammal collection’s history as part of the Museum’s greater history is documented in Denver's Natural History Museum: A History (Johnson et al., 2013). The growth of the mammal collection can also be traced back to the incorporation of the Colorado Museum of Natural History (CMNH) in 1900 with the acquisition of Edwin Carter’s bird and mammal specimens. Mammal collection activity tracks different institutional foci and staffing over the last 119 years. The first period of real growth begins 1900–1910 and reflects collecting efforts in Colorado and New Mexico to document species occurrence and acquire specimens for public display in exhibits and dioramas. In 1910, mammalogist and ornithologist Jesse Figgins was hired as Museum director and initiated a period of growth centered on building the research collections and public exhibits. Expeditions in the North America (Rocky Mountain region; Alaska 1921) and abroad (South America 1926, 1928) supported this growth.
Following Figgins, Alfred Bailey was hired as director in 1936; he remained until his retirement in 1969. Once again, collecting in the Rocky Mountain region continued in earnest, coupled with international expeditions to Central America (1931), Australia (1949), Campbell Island (1958), Galapagos Islands (1960), and Botswana (1969). As during the Figgins era, the fruits of these expeditions are still on display in the Museum’s diorama halls. During this time, Bailey also hired two mammal curators: Albert Rogers (1948–1958) and Henry Wichers (1959– 1972).
From 1980 to 2003, a major spike in growth occurred under the direction of Carron Meaney (1985–1991, curator of mammals) and Cheri Jones (1992–2003, curator of mammals) with focused collecting trips in Colorado and Wyoming. During this period, many improvements were made to collection storage conditions and protocols; these improvements had a positive impact on the mammal collection. This included improvement of collections care by increased environmental monitoring and implementation of an integrated pest management (IPM) program in 1988 followed by accreditation by the American Society of Mammalogists in 1989. In 1999–2001, funding from IMLS (IC-90-194-99) was used to improve storage conditions (cabinets, compactors, and specialized storage mounts) for 600 large-bodied mammals stored in a 5,000-ft2 shared collections area of the Museum.
In August 2006, John Demboski was hired as the curator of vertebrate zoology; he is responsible for both the mammal and bird collections. Demboski began an aggressive program of growing both collections through mammal collecting (in part funded by NSF DEB-0716200) and salvage (including birds). This burst of activity has resulted in the greatest amount of growth (120%) in the mammal collection’s history (2006–2019) when compared to the previous 119 years. This recent growth has also benefited from salvaged or collected mammals obtained from Colorado Parks and Wildlife, United States Fish and Wildlife Service, Mesa Verde National Park, Denver Zoo, Colorado Natural Heritage Program, and wildlife rehabilitation centers among other agencies and groups.
Concurrent with this rapid growth over the last 13 years was the formation of an in-house frozen tissue collection; tissues have been archived from approximately 8,500+ mammal specimens as of July 2019. The frozen tissue collection continues to grow as every incoming specimen is sampled. In addition, ecto- and endoparasites are now sampled from all incoming specimens and housed as a separate collection (~7,500 specimen lots). Both the frozen tissue subcollection and the parasite collections have substantially increased the overall value and utility of the mammal collection.
Demboski also instituted rigorous curatorial procedures; development of a mammal collection manual; more discriminatory accession policies (e.g., only specimens with provenance); and processing of a large backlog of accessioned specimens from the 1990s. In 2010, mammal specimen records were migrated to Arctos, and paper cataloging ceased. In spring 2011, a National Science Foundation grant ($500,000) was awarded to Demboski to support the purchase of new cabinetry (120 Delta Design cabinets with trays), inventory, reorganization, and databasing of the mammal collection in preparation for the 2014 move into the new facility. This funding also allowed a full-time collections technician, Meghan Truckey (now the Museum’s registrar), to be hired for a three-year term through 2014. In 2014, the collection was moved to the new Avenir Collections Center, and since then there have been ongoing projects around organizing the collection to make the best use of space in the new facility.
The ongoing growth of the mammal collection by Demboski has been spurred on by the need to better document mammalian diversity (including genetic diversity) in the southern Rocky Mountain region. This is important given the rapid influx of people into the region, particularly Colorado’s Front Range, over the last 20 years coupled with a growing concern for the effects of rapid climate change. Given its 150-year span, the mammal collection provides an important, baseline resource from which to compare and contrast findings based on contemporary sampling of the mammalian fauna.