Assemblages of Small Mammals in North-Central Kansas : Historical and Ecological Implications

Small mammals were trapped on four habitats; cropland, roadside ditch, pasture, and remnant grassland. The small mammal community of each of these habitats were compared on the basis of richness, evenness, diversity, and similarity. The cropland was found to most resemble the pasture. When richness, evenness, and diversity were comparison characters the ditch most resembled the remnant grassland; however, when similarity was the comparison character the ditch most closely resembled the pasture. The population dynamics, habitat preference; probable historical occurrence, and impact of human activities on individual species were also examined. The only species that was permanent in all four habitats was the deer mouse, Peromyscus maniculatus. The cotton rat, Sigmodon hispidus was a permanent species in the remnant grassland and a semi-permanent species in the ditch. Populations of S. hispidus showed dramatic declines during the drought that significantly altered community structures. Reithrodontomys megalotis, western harvest mouse, was a transient on all of the habitats but the remnant grassland were it was a permanent species. The western harvest mouse was not appreciable affected by the drought. There is probably no native prairie ecosystem remaining in western Kansas that is reflective of the biotic communities that were extant prior to the arrival of the European settlers. At that time this area was inhabited primarily by Arapraho and Cheyenne Indians with occasional incursions by the Kaw, Pawnee, Sioux, Kiowa, and Comanche tribes (Choate and Fleharty, 1975) as they exploited the vast herds of bison that roamed these prairies (Darton, 1916). After gold was discovered in Colorado, the Smoky Hill Trail was established in 1859 (Choate and Fleharty, 1975). Military outposts, like Fort Hays (founded in 1865), were established to protect the ever increasing numbers of white settlers as they moved westward on wagon trains, stage lines, and eventually the railroad. The Kansas-Pacific railroad reached Hays on 16 Oct. 1867, and Hays City was formally founded on 23 Nov. 1868. According to records kept at Fort Hays the bison had disappeared by 1877. Agricultural experimentation began at Hays City in 1867 or 1868, when W. E. Webb enclosed 25 acres with a board fence and, in an attempt to turn over five acres of native grassland, ruined a number of plows (Hays Sentinel, 18 Jan. 1878). By 1870, Hays City had a population of 320 as did the adjacent Fort (Walker, 1872). In 1873 and 1874, Martin Allen planted a variety of trees but grasshoppers and drought killed them all. Allen wrote about the hard surface of the ground, stating that it “would shed rain, nearly equal to a shingle roof” (Hays Sentinel, 8 Aug. 1879). Richard Smith Elliott sowed wheat, rye, and barley at Ellis on 20 Oct. 1870 and wrote “the work of redeeming the domain of the buffalo was begun” (Elliot, 1883). In April 1871, 120 acres of grassland were turned over near Ellis by Dr. Louis Watson. Of this 100 acres were planted to corn and sorghum and the remainder was sown to wheat, barley, and rye in September. Adverse weather conditions along with an attack by grasshoppers caused Dr. Watson to cease his experiment by the winter of 1872 (Watson, 1872). Louis Agassiz from Harvard came to Hays on the Kansas Pacific railroad and found the area “eminently adapted to the culture of wheat.” He predicted that this area soon would be one of the leading wheat-producing areas of the world (Hays Sentinel, 8 March 1876). These feeble attempts at agriculture were only harbingers of things to follow. There was no large-scale agriculture in Ellis County until 1876, when German-Russian immigrants arrived. By 1877, 1321 acres were planted to wheat and 1310 to corn. This increased the following year to 4037 acres of wheat and 3226 acres of corn (Hays Sentinel, 9 May 1879). As prairies were plowed under to serve as croplands, roads and borrow ditches were constructed, and small villages were founded, native vegetation was impacted and small mammal assemblages were altered. A few remnants of the native prairie were “saved” but by closing them to grazing and “protecting” them from fire, these too were altered. The remaining prairie was fenced and subjected to various intensities of grazing by domestic livestock. Investigations in western Kansas have examined various aspects of small mammal ecology as they relate to these altered ecosystems. These have included studies on the use of fencerows, croplands, and grazed lands (Kaufman and Kaufman, 1989; Navo and Fleharty, 1983; Fleharty and Navo, 1983; Kaufman and Kaufman, 1990b), remnant prairies (Fleharty and Mares, 1973; Hansen and Fleharty, 1974; Choate and Fleharty, 1975; Fleharty, 1972), and riparian communities (Fleharty and Stadel, 1968; Frydendall, 1969) as small mammal habitat. Although these studies have provided significant information on small mammal ecology, many were of relatively short duration or had relatively few sampling periods and were, of course not conducted under similar climatic regimes. Additionally, cropland ecosystems have not been studied systematically during a complete rotational cycle as often is practiced in dryland farming of western Kansas. The purpose of this study was to sample small mammal populations from four ecosystems that have been established under the influence of human activities to better understand 1) the effects that these changes have had on the assemblages of small prairie mammals, and 2) the population dynamics of small mammals through extensive sampling in these “artificial” ecosystems under similar climatic regimes