Desert Cottontail Use of Natural and Modified Pinyon- Juniper Woodland

Desert Cottontail Use of Natural and Modified Pinyon-Juniper Woodland

Item Type text; Article

Authors Kundaeli, J. N.; Reynolds, H. G.

Citation Kundaeli, J. N., & Reynolds, H. G. (1972). Desert cottontail use of natural and modified pinyon-juniper woodland. Journal of Range Management, 25(2), 116-118.

DOI 10.2307/3896798

Publisher Society for Range Management

Journal Journal of Range Management

Download date 27/09/2021 20:42:20

Item License http://rightsstatements.org/vocab/InC/1.0/

Version Final published version

Link to Item http://hdl.handle.net/10150/647402 116 KUNDAELI AND REYNOLDS

grazing pangolagrass pastures re- and blood of cows grazing pangola- PALTING,J. F. EASLEY,J. W. CAR- ceiving different phosphate fertili- grass. J, Range Manage. 23: 136-139. PENTER,AND MARVIN KOGER. 1963. zer. Fla. A’gr. Exp. Sta. Tech. Bull. NUTRIENTREQUIREMENT OF BEEFCATTLE. Water, phosphorus, calcuim, ash 735. 55 p. 1970. Nat. Res. Council National and protein of the heart, liver and KIRK, W. G., R. L. SHIRLEY, J. F. Academy of Sciences. Washington, muscle of Hereford, Brahman and EASLEY,AND F. M. PEACOCK. 1970b. D. C. 55 p. Hereford-Brahman crossbred cattle. Vitamin A and B-carotene in liver SHIRLEY,R. L., D. D. HARGROVE,FLORA J. Anim. Sci. 22393-395.

sideoats grama (B. curtipendulu Desert Cottontail Use of Natural and (Michx.) Torr.)-contribute about Modified Pinyon- Juniper Woodland’9 2 two-thirds of the total. Over 30 species of perennial grasses make JOHN N. KUNDAELI AND HUDSON G. REYNOLDS up the remainder of the production. Game Management Officer, College of African Wildlife, Moshi, Tanzania; and Forb production is about half Principal Wildlife Biologist, Rocky Mountain Forest and Range Experiment that of perennial grasses. No forb Station, Forest Service, U. S. Department of Agriculture, Tempe, Arizona. species dominate the composition; of the more than 50 species involved, Highlight clearing upoln the desert cottontail most abundant genera include: Pinyon-juniper woodland, a habitat in southern New Mexico. Recom- vetch (Viciu spp.), globemallow for desert cottontails throughout much mendations are given for coordinat- (Sphuerulceu spp.) goosefoot (Chen- of the West, is often cleared to im- ing clearing activities with the opodium spp.), and buckwheat (Eri- prove grazing conditions for livestock. habitat needs of cottontails. ogonum spp.). In southern New Mexico, habitat con- In 1963, permanent pellet sam- ditions for cottontails can be main- Study Area and Methods tained or enhanced during clearing pling stations were located at me- operations by preserving some combi- This study was conducted on chanically spaced intervals on the nation of 70-90 down, dead trees and 13,000 acres of the Ft. Bayard Ex- entire experimental area at an in- living shrubs per acre. perimental Forest, about 10 miles tensity of 25 per sectioa (approxi- east of Silver City, New Mexico. mately 450 plots). In 1965 sampling Desert cottontails (Sy2viEagu.s au- The area includes only elevations intensity was increased to 225 sta- duboni Baird) are distributed of 6,000 to 7,000 ft in the pinyon- tions per section on the southern widely throughout the western juniper. Rainfall averages about 16 one-third of the area. United States. These animals pro- inches. Considerable diversity of PelIet plots at each sample station vide substantial recreational hunt- soils and topography provide a com- consisted of four belts laid out in ing. For example, about 29,000 plex environment for plant growth. cardinal directions. Each belt con- hunters harvest over 185,000 cotton- Percent density composition of trees tained l/400 acre (3 by 36.3 feet). tails annually in Arizona (Smith, is: pinyon (Pinzcs edulis Engelm.), Presence or absence of accumulated 1962) while expending about 40; alligator juniper (Juniperus cottontail rabbit pellets was noted $640,000 (Davis, 1962). Mainten- deppeana Steud.), 24; gray oak annually on each sampling belt. ance of cottontail rabbit production (Quercus griseu Liebm.), 24; Utah Trees and shrubs were counted to satisfy recreationists depends juniper (J. osteospermu (Torr.) around the center of each sample upon proper habitat management. Little), 10; other trees (15), 2. Simi- station on a l/lo-acre plot (37.2-foot The range of cottontails includes larly, shrub composition is: hairy radius). 60 million acres of pinyon-juniper mountainmahogany (Cercocurpus Herbaceous vegetation was esti- woodland in the Rocky Mountain breuiflorus A. Gray), 47; gray oak mated periodically by species on and Intermountain Regions (Forest (less than 6 ft tall), 20; Wright silk- belts 1 by 24 feet in size superim- Service, 1958). This woodland, tassel (Gurryu wrightii Torr.), 18; posed over the pehet plots. Esti- among other values, provides im- skunkbush (Rhus trilobutu Nutt.), mates of herbage were corrected to portant forage for livestock. Many 10; other shrubs (25), 5. Tree den- actual weight by double sampling public and private land managers sity varies from none on 7% of the (Wilm et al., 1944). Vegetation continue to clear areas of pinyon- area to sites with more than 250 samples were dried so that produc- juniper to improve forage produc- plants/acre. Some areas support an tion could be expressed as pounds tion for livestock. This paper re- equal density of shrubs, although of air-dry material per acre. ports the effect of pinyon-juniper 17% of the area is without shrubs. Pinyon-juniper was removed in Perennial grass production av- various amounts and by several 1 Received May 2 1, 197 1. erages about 300 Ib./acre. The methods on the southern one-third 2 Results reported are based on Mr. Kundaeli’s MS thesis to Colorado dominant species-blue grama (Bou- of the experimental area in 1965. State University. telouu grucilis (H.B.K.) Lag.) and The experimental design consisted DESERT COTTONTAIL 117

Table 1. Occurrence (%) of desert cottontail pellets in relation to tree density and approximately 125 shrubs per (no./acre), shrub abundance (na./acre), and berbaceous vegetation Produc- acre use by cottontails decreases tion (lb./acre) on Ft. Hayard in 1966. (Table 1). Overstory trees can affect cottontail use by suppressing shrub>. Tree density above 160 per acre sup- presses ahrub abundance. If shrubs are reduced by tree competition below optimmn habitat conditions of about S5 shrubs per acre, cottontail use is depressed. Within the range of 150 to 370 pounds per acre production of her- of five randomized treatments in ran be too few or to” dense for best baceous vegetation does not seem each of two blocks. Each treatment cottontail habitat conditions. to affect cottontail use. plot contained 300-500 acres. In To separate the effect of shrubs and overstory trees upon cottontail one treatment, trees were uprooted, Use of Modified Areas piled, and burned. In another presence, pellet densities were mea- treatment, trees were uprooted but sured on areas with and without Modifications of cottontail habitat by different methods of tree re- left where they fell. Retention of trees. An area of 300 acres near “p- trees on steep slopes and northerly timum for cottontail presence (Fig. moval resulted in differences in cot- exposures constituted a third treat- 1) averaging 86 shnlbs/acre and 57 tontail use. Pellet densities were ment. On a fourth area, trees were trees/acre had a pellet density of significantly lower (0.05 level) from thinned to a density of 100 trees/ 2.8 per square foot. An adjacent the control plot where all trees acre by felling with a chain saw. area of comparable size and density were uprooted, piled, and burned The fifth area was left undisturbed. of shrubs but without trees, had a (Table 2). Pellet densities were significantly higher than the con- In 196R, a supplemental study density of 3.1 pellets per square was made of cottontail use of treat- foot. This comparison suggests that trol where trees \,‘ere uprooted but ment areas. Accumulated cottontail if sufficient shrubs are present, left intact. The thinning treatment rabbit pellets were counted on ran- the habitat will be occupied by did not differ significantly from the domly selected sample points on cottontails whether living trees are control area. Since the treatment belts of l/400 acre within the mid- present or not. areas were comparable in density dle of each treatment area. Such Cottontail use is strongly related of shrubs (50-59 per acre) the dif- measurements permitted quantita- to ahrub density. With an increase ferences in cottontail use suggest tive comparisons between relative from 53 to 85 shrubs per acre, cot- that abundance of down, dead trees rabbit abundance, as measured by tontail use increases; between X5 influenced habitat conditions. pellet counts, and characteristics and condition of the surrounding vegetation.

Use of Undisturbed Areas Use of natural areas by cottontails was extensively surveyed on 9,000 acres of undisturbed pinyon- juniper in 1966. Evidence of rabbit ;se was found on 83% of the area. Within use areas, however, certain combinations of trees, shrubs, and herbaceous plants were preferred. Evidence of cottontails was greatest (91% of plots with pellets) where per acre amounts of vegetation averaged 85 trees, R5 shrubs, and 270 lb. of perennial grass (Table 1). Pellet occurrence at this tree density differed significantly (0.05 level) from that at higher and lower densities of ahrubs and trees. This relation suggests that woody plants 118 KUNDAELI AND REYNOLDS

Table 2. Relation of cottontail pellet densities (no./ftz) to shrubs and down shrubs furnish the primary cover trees as affected by treatment (after Kundaeli, 1969). for cottontails. About 85 shrubs/ acre furnish ideal habitat con- Cover complex (no./acre) ditions. Living trees influence hab- Cotton- tail Down itat conditions only indirectly by Treatment pellets Shrubs Trees Total suppressing shrubs when tree num- bers exceed 160 per acre. However, Uprooting all trees 3.2 59 31 90 down trees can serve in lieu of Thinning to 100 trees/acre 2.7 58 14 72 shrubs as cover. From 70 to 90 units No treatment 2.4 57 4 61 of down trees and/or living shrubs Uprooting, piling and burning 1.0 50 6 56 seem to provide best habitat con- di tions. Uprooting, piling, and burning investigate trees plus shrubs reached 70 per To further the effect of all pinyon-juniper trees depressed acre; at greater densities of cover, of down trees upon cottontail use, cottontail rabbit use. Where there pellet density decreased, but re- various density combinations of are less than 85 shrubs/acre, ho,w- shrubs and down trees were related mained comparatively high at the ever, pinyon-juniper control can to presence of rabbits as measured highest density of cover measured- enhance habitat conditions for cot- by pellet densities. Down, dead 130 + per acre (Fig. 2). tontails, if sufficient down trees are Further evidence of the desired trees were assumed to be equivalent retained to total 70-90 per acre in to shrubs in their habitat contri- level of down trees and live shrubs combination with living shrubs. for best cottontail habitat is pro- bution. Where density of living shrubs ex- vided by presence and absence data Cottontail pellet density in- ceeds 70-90 per acre, habitat will creased until cover density of down for cottontail pellets (Table 3). be improved little by leaving down The combined cover of 65 shrubs trees. plus 20 down trees per acre seemed to provide adequate habitat con- Literature Cited ditions. The difference in percent DAVIS,W. C. 1962. Values of hunt- of plots with pellets is significant ing and fishing in Arizona 1960. (0.05 level). Univ. Ariz. Bur. Bus. & Publ. Res. Spec. Study 21. 61 p. Conclusions FOREST SERVICE. 1958. Timber re- In pinyon-juniper woodland, as sources for America’s future. Forest Service, U. S. Dep. Agr. Forest Res. represented by the Ft. Bayard area, Rep. 14. KUNDAELI, J. N. 1969. Cottontail Table 3. Occurrence (%) of cotton- rabbit (Sylvilagus audubonii cedro- tail pellets in relation to density philus Nelson) response to pinyon- (no./acre) of down trees and shrubs. juniper removal. MS. Thesis, Colo. State Univ. 57 p. SMITH,R. H. 1962. Cottontail rabbit Densities Plots with survey and hunt information. Ariz. Down pellets Game SCFish Dep. W53RlZ/WP3Jl, Shrubs Total trees (%) 2, 3, 8e4. 12 p. FIG. 2. Relation between collective cover WILM, H. G., D. F. COSTELLO,AND G. E. density of down, dead trees and living 0 23 23 61 KLIPPLE. 1944. Estimating forage shrubs, and density of desert cottontail 20 65 85 91 pellets on Ft. Bayard treatment areas yield by the double sampling method. 52 90 142 91 in 1968. J. Amer. Sot. Agron. 36:194-203.

The Trail Boss portrays a man, a man willing to accept responsibility, and a man capable of delivering the goods in the face of adversity. The dedication of The Trail Boss to the herd makes it a fitting symbol of the range manager’s dedication to animals, land, and people. Both The Boss and today’s range manager are more than just cow- boys. (Harold F. Heady. J. Range Manage. 20:283)