Wolff, TER-QUA PalArch’s Journal of Vertebrate Palaeontology, 10(4) (2013) HOME ON THE RANGE: BIOGEOGRAPHIC DISTRIBUTION OF BISON IN ARIZONA Sarah E. Wolff* * University of Arizona School of Anthropology, University of Arizona Tucson, AZ 85721 [email protected] Sarah E. Wolff. 2013. Home on the Range: Biogeographic Distribution of Bison in Arizona. – Palarch’s Journal of Vertebrate Palaeontology 10(4) (2013), 1-11. ISSN 1567- 2158. 11 pages + 3 figures, 1 table. Keywords: Bison, Biogeography, Arizona, Southwest historical ecology ABSTRACT The American bison are traditionally thought of as animals of the vast plains and grasslands, but paleontological and archaeological evidence supports the view that the biogeographic range of bison extended throughout the continental United States to include the American Southwest and Arizona. During the Pleistocene (2,588,000 BP to 11,700 BP), there are several paleontological and archaeological signatures of bison herds in Arizona. From approximately 12,000 BP to AD 1 there is no evidence for bison in the area. This changes around AD 1 when the climate became more favorable, and bison expanded back into Arizona. The last historic bison remains in Arizona date to AD 1650. From AD 1650 until the early 1900s, there are no bison documented in Arizona. Reintroduction of bison to Arizona’s national forests and ran- ches began in the early 1900s and continues to today. Bison can still be seen on the Arizona landscape demonstrating the temporal longevity of the biogeographic distribution of bison in Arizona. © PalArch Foundation 1 Wolff, TER-QUA PalArch’s Journal of Vertebrate Palaeontology, 10(4) (2013) Introduction Arizona is a somewhat surprising area to find bison because of the desert ecology that Biogeographic distribution of bison as previous- dominates the state today. Grassland dots ar- ly established exclude the American Southwest eas in the north and south of the state, while (Allen, 1974; Lott, 2002), but paleontological and piñon-juniper woodlands now dominate the archaeological excavations demonstrate that bi- northeastern corner. Ponderosa pine forest and son once roamed not just the grass plains of the spruce-fir forests occur in isolated patches in interior but also the arid regions of the South- the northeastern areas of the Arizona (Lomo- west (Mead, 2006; Scott, 2008). This evidence es- lino et al., 2010). The Sonoran desert dominates tablishes a lasting consistent marginal presence much of the central to Southwestern part of the of bison in Arizona and the Greater Southwest. state. There are also intrusions of the Mojave Although not the ideal habitat for bison, Arizona, (Northwest), Great Basin (Northeast), and Chi- in particular, hosted small populations over such huahuan (Southeast) Deserts. Four deserts meet a long period of time that it must be considered in Arizona, none of which is ideal habitat for possible bison range and habitat. this species. However, Arizona is also a state that has several mountain range uplifts that al- Bison Range low for water and a variety of vegetation. Desert bighorn sheep, Ovis canadensis, is an example Spanish and English settlers historically report- of a large ruminate herbivore that inhabited the ed dense herds of bison in the Great Plains east desert areas of Arizona in prehistoric times in of the Rocky Mountains (Allen, 1974; Hornaday, dense numbers, and now exists in sparse num- 2002; Lott, 2002). Bison, as the icon of the Great bers (Monson, 1980). Plains and the west, was perpetuated by much Although Arizona is currently dominated popular culture through popular western art- by desert scrub, this has only come about dur- work such as that by George Catlin, 1796 -1872 ing the Holocene (10,000 years ago to present). (Olsen, 2008). Today, images of bison grace the During the Pleistocene (2,588,000 BP to 11,700 state quarters of Kansas, North Dakota, and BP) Arizona fluctuated in environment, and Montana. A bison also appears on the state flag during the late Wisconsin glacial stade (14,000 of Wyoming. years ago) woodland savanna persisted through Despite this popular western image of bi- much of the state (McDonald, 1981). During son, historical records demonstrate that bison glaciation periods, the cold jet stream across stretched from nearly the Atlantic to the Pa- the northern part of North America caused a cific Oceans (Meagher, 1986). Bison natively cold cycle, which shifted the warm Westerlies appeared in areas far removed from the Great southward bringing heavy precipitation to the Plains including Idaho, Oregon, Utah, New York, now arid American Southwest (Lomolino et Pennsylvania, Virginia, North and South Caro- al., 2010). The increased rain in the American lina, Georgia, Florida, and the Mexican states Southwest changed the flora and fauna of the of Tamaulipas, Nuevo Leon, Coahuila, Chihua- area. During the Pleistocene, the desert was con- hua, and Durango (Allen, 1974: 74, 128, 129). fined to a small area in the southwest corner Regional names hint at the historic range of bi- of the state. The dominant vegetation in the son, such as Buffalo Creek in New York (Allen, rest of the southern part of was piñon-juniper 1974). Buffalo is the given name for eleven areas woodlands/chaparral/grasslands. In the North- or cities throughout the United States, including east corner of the state, mixed conifer forests the states of New York, Iowa, Kansas, Kentucky, dominated the landscape. Pluvial lakes, spruce- Minnesota, Illinois, Indiana, Montana, North Da- fir forests, and alpine areas dotted the state (Lo- kota, Missouri, and Wyoming. Cibola, the Span- molino et al., 2010). ish word for bison, is the given name for several areas in the southern United States such as in Bison Evolution Texas, New Mexico, and Arizona. Although historic records do not indicate bi- Bison are a northern adapted bovid that evolved son living in Arizona, there is paleontological in the large herbivore grazing niche across Eur- and archaeological evidence of the history of asia. Bos, another large bovid commonly called bison in the region. cattle, occupied the more southern grazing © PalArch Foundation 2 Wolff, TER-QUA PalArch’s Journal of Vertebrate Palaeontology, 10(4) (2013) niche. To the far south, buffalo occupied a simi- and B. antiquus became the prominent North lar habitat, such as water buffalo in Southeast American species until its extinction approxi- Asia and Africa (Guthrie, 1970). Because bison mately 10,000 B.P. (Lott, 2002). After 10,000 were the cold adapted bovid in Eurasia, their BP, B. occidentalis appears in part of the vacant migration through and habitation of Beringia, niches left open by B. antiquus. B. occidentalis the area of land connecting Eurasia to North appeared to be an offshoot of B. priscus that America, was possible. persisted in northern latitudes during the Wis- Beringia was a natural habitat for bison and consin glaciation period (26,000 to 13,300 B.P.). allowed them access into the New World, while After the Wisconsin glaciation period, this cattle were not able to enter North America un- smaller bison spread down into the B. antiquus’ til the introduction by Europeans in the 1500s now vacant territory (Guthrie, 1970). Bison occi- and 1600s (Sheridan, 1988). The local climate dentalis was a brief species and never expanded and geology created an ice-free refugium across into all of B. antiquus’ territory, including Arizo- this land bridge that could support megafauna, na and California (Guthrie, 1970; Lott, 2002:64). such as bison (Shapiro et al., 2004). Beth Shap- By approximately 5,000 BP, B. bison, modern iro’s ancient DNA research suggests that bison bison, had replaced B. occidentalis (Lott, 2002). inhabited Beringia from ca. 300,000 to 130,000 The exact genetic and evolutionary relationship B.P. Bison then moved southward from ca. between these species is unknown and highly 130,000 to 75,000 B.P., during an interglacial pe- debated. riod (Shapiro et al., 2004). However, these dates are not without controversy. Paleoindian Period (15,000-8,000 BCE) Bison fossil data presents and interprets a different migratory trajectory. Evidence from Prior to human colonization in North America, Bell et al. (2004) suggests an intermediate ar- it is likely that both, B. antiquus and B. latifrons rival of bison into North America, ca. 210,000 populated Arizona and the Greater Southwest to 160,000 B.P. Finally, fossil evidence of bison (McDonald, 1981; Skinner & Kaisen, 1947). Bi- in Sonora, Mexico, suggests an early arrival of son latifrons remains have been found at pale- bison ca. 570,000 to 310,000 B.P (Mead et al., ontological (non-human) sites such as Greater- 2006). All that can be said conclusively is that ville/Empire South (Agenbroad & Haynes, bison migrated from Eurasia across Beringia 1975; Lindsay & Tessman, 1974). Further south into the New World sometime between ca. in Mexico, there are several reports of extinct 570,000 to 75,000 B.P. bison fossils such as B. antiquus, B. latifrons, The open grasslands of North America were and B. priscus (Lindsay & Tessman, 1974; Mead exploited by bison and then undergo an adap- et al., 2006). Extinct bison fossils, similar to Bi- tive radiation of the genus across the North son antiquus, have also been found in the Mo- American continent. Several species of bison jave Desert of Southern California and Nevada. evolved to fill this open niche, although several Interestingly, the bison in the Mojave Desert arguments are made for the differential evolu- are underrepresented compared to other large tion of bison species in North America. A brief mammals, such as mammoths, horses and cam- synopsis of these arguments follows. els, but the numbers do suggest that bison were There were four key species that possibly present in varying abundance in different loca- evolved into B.