University of Kansas Publications
Museum of Natural History

Vol. 10, No. 7, pp. 553-572, 4 pls., 3 figs.
May 4, 1959

Home Range and Movements of the Eastern Cottontail in Kansas

By

DONALD W. JANES

University of Kansas
Lawrence
1959

University of Kansas Publications, Museum of Natural History

Editors: E. Raymond Hall, Chairman, Henry S. Fitch,
Robert W. Wilson

Volume 10, No. 7, pp. 553-572, 4 pls., 3 figs.
Published May 4, 1959

University of Kansas
Lawrence, Kansas

PRINTED IN
THE STATE PRINTING PLANT
TOPEKA, KANSAS
1959

Home Range and Movements
of the Eastern Cottontail in Kansas

By

DONALD W. JANES

INTRODUCTION

A knowledge of the home range and movements of the cottontail (Sylvilagus floridanus) is one of the most important prerequisites for estimating effectively its numbers and managing its populations. By comparing results obtained from different methods, previously used, for determining the size of the home range I have attempted to develop a more valid procedure.

The study here reported upon was made on the University of Kansas Natural History Reservation (Sec. 4, T. 12S, R. 20E), the northeasternmost section of Douglas County, Kansas, approximately 6½ miles north-northeast of the University campus at Lawrence. The 590-acre reservation, situated in the ecotone between the eastern deciduous forests and the prairie of the Great Plains near the north edge of the Kansas River Valley, has been protected as a "natural area" since 1948 (Fitch, 1952). It consists of tree-covered slopes, and flat grass-covered hilltops and valleys. Two limestone outcrops follow the contours about five and 20 feet below the tops of the hills.

The 90-acre study area consists of a valley bordered on the north by a wooded slope and on the southeast by another wooded slope adjacent to a narrow hilltop, east of which is another wooded slope. The area is thus an alternating series of three wooded slopes and two grass-covered, relatively level areas.

The wooded slopes rise from the valley for about 125 feet at a grade of approximately 16 per cent. There is a sharp increase in grade to 36 per cent 100 feet below the top of the hills. A natural terrace 50 feet to 100 feet wide parallels the hilltop at the base of the 36 per cent incline.

The vegetation of the northwest-facing wooded slopes has been described by Packard (1956). It consists of American elm (Ulmus americana), shagbark hickory (Carya ovata), chestnut oak (Quercus muehlenbergii), black oak (Quercus velutina), and black walnut (Juglans nigra), in that order of dominance. Honey locust (Gleditsia triacanthos) and hackberry (Celtis occidentalis) are also present. Shrubs and herbs of the lower story include greenbriar (Smilax hispida), wild grape (Vitis vulpina), Virginia creeper (Parthenocissus quinquefolia), coralberry (Symphoricarpos orbiculatus), gooseberry (Ribes missouriense), bluegrass (Poa pratensis), sedges (Carex sp.), poison ivy (Rhus radicans), and white snakeroot (Eupatorium rugosum).

The flat hilltops are covered by a mixture of grasses and forbs but are dominated by awnless brome (Bromus inermis). Foxtail (Setaria glauca), false redtop (Triodia flava), and panic grass (Panicum clandestinum) also occur commonly. Awnless brome is dominant in the valley (Pl. 46, fig. 1; Pl 47, fig. 2) except in the eastern end where bluegrass is dominant (Pl. 45).

Near the tops and bottoms of the slopes barbed wire fences separate the woodlands from the grasslands, which were grazed until 1948. The borderline between woods and grasslands is well defined but woody plants are rapidly encroaching into the grasslands. Young Osage orange (Maclura pomifera), American elm, and hackberry are common trees encroaching on the grasslands. The edge vegetation between woods and fields (Pls. 45 and 47) includes smooth sumac (Rhus glabra), coralberry and wild plum (Prunus americana). The lowland edges are characterized by blackberry (Rubus argutus), greenbriar and elderberry (Sambucus canadensis). Plates 45, 46 and 47 all show local habitat in situations where traps were actually operated. Fitch (1952:8-22), Leonard and Goble (1952:1015-1026) and Martin (1956:366-372) have described parts of the Reservation that include the study area.

I am grateful to Professor Henry S. Fitch for guiding my work, to Professor Rollin H. Baker for suggestions and encouragement in the early part of the study, to Mr. Robert L. Packard for certain trapping records that supplemented my own, and to Professor E. Raymond Hall for valuable suggestions. Norma L. Janes, my wife, typed the manuscript. Photographs were taken by me. The State Biological Survey of Kansas provided funds, equipment, and transportation.

METHODS AND TECHNIQUES

Schwartz (1941), Dalke and Sime (1938), Dalke (1937 and 1942), Hendrickson (1936), and Allen (1939) estimated the home range of the cottontail by drawing, on a map, straight lines that connected all marginal points of capture in live-traps. The resulting home ranges were polygonal figures. Haugen (1942) altered this method by drawing lines that connected points midway between the actual points of capture and the next outermost traps in the grid. Fitch (1947) used a method for enclosing all points of capture in a circle or ellipse that represented the home range boundaries and expressed home range as the diameter of these figures. Another method, which has been used to determine the home range of birds, is to map the movements of an individual as it is observed. Stebler (1939) suggested the use of tracking records to determine home range. Connell (1954) expressed home range of cottontails as the average distance traveled from a computed center of activity. The method was originally proposed by Hayne (1949).

The methods used by other investigators to calculate the home range of the cottontail have yielded estimates varying from 0.1 acre to 100 acres. Such wide variations in the estimated size of home range may result from the use of different methods and from insufficient data. The data obtained from live-trapping are not fully adequate because traps cannot sample, in time and space, the entire home range of an individual. Also, "trap habit" or "trap shyness" may distort the apparent shape of the home range. In order to compare these methods I have calculated home range from my data by each of five different methods. The results are shown in Table 1.

No two methods yielded exactly the same results. To utilize all available data for each individual, I recorded on a map the locations of capture in live-traps, nests and forms, locations where the animal was observed in the field and the routes that it took between them. At the end of the study a line was drawn on the map to enclose the areas where the cottontail was known to have been.

Live-traps were operated intermittently at 130 stations between December 8, 1954, and February 10, 1956. Sixteen cottontails were marked in the same area by Robert L. Packard in 1954. Data from 7850 trap nights were used in this study. The traps were set at fifty-foot intervals and the pattern approximated that of a grid in habitat favorable for cottontails such as at edges of woodland. In wooded areas traps were placed at fifty-foot intervals