Until recently it was believed that the population of eastern woodrats (Neotoma floridana) in Pine Hills, Union County, Illinois, represented the only extant population remaining in the state. Trapping at sites formerly occupied by woodrats and in areas with suitable habitat resulted in the documentation of additional populations at Fountain Bluff, Little Grand Canyon, and Horseshoe Bluff, Jackson County. Woodrats currently are more numerous and have a wider distribution in southern Illinois than previously believed

Emerson, Robert E.

Feldhamer, George A

Monty, Anne-Marie

Wagle, Elizabeth R.

English

OpenSIUC

Southern Illinois University CarbondaleOpenSIUCPublications Department of Zoology1995Recently Discovered Populations of EasternWoodrats (Neotoma floridana) in Southern IllinoisAnne-Marie MontySouthern Illinois University CarbondaleElizabeth R. WagleSouthern Illinois University CarbondaleRobert E. EmersonIndiana University School of MedicineGeorge A. FeldhamerSouthern Illinois University CarbondaleFollow this and additional works at: http://opensiuc.lib.siu.edu/zool_pubsPublished in Transactions of the Illinois State Academy of Science, Vol. 88 No. 1 and 2 (1995).This Article is brought to you for free and open access by the Department of Zoology at OpenSIUC. It has been accepted for inclusion in Publicationsby an authorized administrator of OpenSIUC. For more information, please contact opensiuc@lib.siu.edu.Recommended CitationMonty, Anne-Marie, Wagle, Elizabeth R., Emerson, Robert E. and Feldhamer, George A. "Recently Discovered Populations of EasternWoodrats (Neotoma floridana) in Southern Illinois." ( Jan 1995).Transactions of the Illinois State Academy of Science(1995), Volume 88, 1 and 2, pp. 43-47Recently Discovered Populations ofEastern Woodrats (Neotoma floridana)in Southern IllinoisAnne-Marie Monty1, Elizabeth R. Wagle1,Robert E. Emerson2, and George A. Feldhamer11Department of ZoologySouthern Illinois UniversityCarbondale, Illinois 62901-65012Indiana University School of MedicineEvansville Center for Medical EducationEvansville, Indiana 47732ABSTRACTUntil recently it was believed that the population of eastern woodrats (Neotoma floridana)in Pine Hills, Union County, Illinois, represented the only extant population remainingin the state.  Trapping at sites formerly occupied by woodrats and in areas with suitablehabitat resulted in the documentation of additional populations at Fountain Bluff, LittleGrand Canyon, and Horseshoe Bluff, Jackson County.  Woodrats currently are morenumerous and have a wider distribution in southern Illinois than previously believed.INTRODUCTION              Eastern woodrats (Neotoma floridana) historically ranged through the eastern United Statesfrom New York state across the southeast and central states as far west as Colorado (Hall1981).  Populations have been declining recently throughout the species' range.  In thenortheastern United States, woodrat populations are believed to be adversely affected byreduced habitat availability and a nematode parasite, Baylisascaris procyonis, found inraccoons (Procyon lotor) (Woodrat Recovery Workshop 1993).  Woodrats are anintermediate host for B. procyonis and may ingest the nematode eggs while collectinganimal feces (Birch et al. 1994).  Infection leads to lethargy, loss of muscle control, andeventual death (Kazacos et al. 1981, Kazacos and Boyce 1989).The Illinois woodrat (N. f. illinoensis), found in southern Illinois, Missouri, Arkansas,Alabama, Mississippi, and western Kentucky and Tennessee, currently is listed asendangered in Illinois (Herkert 1992).  Based on the presence of old nest sites and woodratmolars, woodrats inhabited numerous sites throughout  the Shawnee National Forest inthe past (Nawrot 1974, Nawrot and Klimstra 1976).    Only three populations remained inIllinois by the 1960’s:  Pine Hills, in Union County, and two sites in Jackson County;Fountain Bluff and Horseshoe Bluff (Crim 1961).  By 1974, the Horseshoe Bluffpopulation was extirpated and only three individuals could be found at Fountain Bluff44(Nawrot and Klimstra 1976).  Since the late 1970's it was believed that the only extantpopulation of woodrats remaining in the state was located at Pine Hills, in southwesternIllinois (Todd Fink, Illinois Department of Conservation Natural Heritage Biologist,personal communication).  Woodrat population density continued to decline at Pine Hills;Nawrot (1974) suggested a "liberal" estimate of 50-75 individuals remained.  The IllinoisDepartment of Conservation  conducted periodic surveys for signs of activity at nest sitesat Pine Hills (Todd Fink, unpublished data) since 1973.  West (1986) estimated that 15-30 woodrats inhabited Pine Hills based on the number of presumed active nests.  A 3-yearlive-trapping investigation of the Pine Hills woodrat population was initiated in July1993.  Associated with this effort was exploratory live-trapping at several previouslyinhabited sites, and areas with appropriate bluff habitat.  Since January 1994, we havedocumented the occurrence of woodrats at three additional sites in Illinois:  FountainBluff,  Little Grand Canyon, and Horseshoe Bluff, Jackson County.STUDY AREASPine HillsPine Hills is composed of north-south oriented limestone bluffs that extend 8.8 km andaverage 24.4 m above the flood plain (Baskett 1925, Weller and Ekblaw 1940).  Woodratshave been trapped along the south- and west-facing bluffs located in sections 9, 16, 21,and 28, T. 11 S, R. 3 W.           Fountain Bluff  Fountain Bluff is located 8 km northwest of Pine Hills.  The lower strata of this isolatedridge are composed of limestone, although thick layers of sandstone form the upper strata.The bluffs reach 61 m above the Mississippi River (Poor 1925).  Woodrats have beenlocated in section 36, T. 9 S, R. 4 W, and section 31, T. 9 S, R. 3 W.Horseshoe BluffWoodrats have been captured at Horseshoe Bluff, a stretch of west-facing sandstone bluffsand fallen boulders located in sections 11 and 14, T. 10 S, R. 3 W.  Horseshoe Bluff islocated about 11 km north of the trapping site at Pine Hills.  Little Grand CanyonThe Little Grand Canyon area is composed of both limestone bluffs and sandstonecanyons that have been eroded by streams.  It is located about 1 km north of HorseshoeBluff and about 8 km east of Fountain Bluff.  Woodrats have been trapped in sections 2and 11, T. 10 S, R. 3 W.MATERIALS AND METHODSTomahawk wire mesh live-traps (16.5 x 16.5 x 48 cm) were set in appropriate habitats atall sites, primarily limestone or sandstone bluffs or outcrops with cracks, depressions,ledges, and overhanging areas.  Traps were baited with cracked corn and sunflower seedsand placed as often as possible at sites with woodrat sign:  stick nests, fecal droppings,feeding debris, and/or tracks.  Polyester stuffing was provided for bedding.  Each capturedanimal was tagged with two individually numbered Monel #3 ear tags.  Mass (to thenearest gram), sex, and reproductive condition were recorded.  Age class (juvenile,45subadult, adult) was determined on the basis of sexual maturity, body mass, and pelagecolor (Wiley 1980).RESULTSPine HillsTrapping at Pine Hills began in July 1993.  A trapping schedule of 40 traps set for 3nights every 3 to 4 weeks was followed.  Although only part of the available habitat hasbeen sampled, as of August 1994, 135 individuals (Table 1) have been captured 675 timesin 1800 trap nights (36.0% trap success rate).  The sex and age ratios of the trappedindividuals change seasonally as most litters are produced in the spring and juvenilesdisperse in the fall.  As traps have been placed at new locations within Pine Hills, newwoodrats have been taken.  This suggests a substantially greater population exists thanpreviously anticipated.Fountain BluffOn 3-4 January 1994, 7 woodrats were captured in 24 trapnights.  Large stick nests andlatrine sites were present at the trapping location.  From February through April 1994,exploratory trapping was conducted at additional locations throughout Fountain Bluff.  InJune 1994 a trapping schedule of 35 traps set for three nights every 3 to 4 weeks wasestablished.  As of July 1994, 19 individuals (Table 2) have been captured 29 times in287 trap nights (10.1% trap success rate).  In addition to the established trapping sites, weare continuing exploratory trapping.Little Grand CanyonOn 10 July 1994, 3 woodrats were captured in 14 traps set at two sites.  Stick nests, mastshells, and fresh scat were present at both sites.Horseshoe BluffOn 27 July 1994, 3 woodrats were captured in 12 traps set.  Although no nests wereobserved, the bluff and forest habitat of Horseshoe Bluff was suitable to support woodrats.Mast shells, tracks, and leaves in rock depressions were the only signs that woodrats werepresent in the area.DISCUSSIONPast assessment of the Pine Hills woodrat population determined the "activity" of nestsites by the presence of fresh vegetation cuttings in the nests, signs of recent building,and fecal droppings.  In monthly trapping at Pine Hills from July 1993 through August1994 very few active nests actually contained fresh cuttings.  Many stick piles wherewoodrats were trapped appeared to be abandoned.  Woodrat nests at Pine Hills do notalways fit the usual description of a large mound of sticks (Hall 1955).  Nests may beprimarily composed of dead leaves and bark as well as sticks.  Because numerous crevicesand deep fissures are present in the bluffs of Union and Jackson Counties, it is possiblethat many more woodrat populations exist without externally visible signs such as sticknests.  Therefore, in order to determine whether woodrats are present at a location that hasno visible stick nests, it is necessary to conduct live-trapping.  More extensive live-trapping will be conducted at the Little Grand Canyon and Horseshoe Bluff areas to46estimate the number of individuals present.  The genetic diversity within and among thefour populations currently is being investigated.  The occurrence of more woodratpopulations than previously known in southern Illinois offers expanded managementopportunities for this endangered species.ACKNOWLEDGMENTSFunding has been provided through the U. S. Forest Service and the Illinois Departmentof Conservation, Natural Heritage Program.  We thank Todd Fink, IDOC, and MikeSpanel and Steve Widowski, Shawnee National Forest, for their assistance and support ofcontinuing woodrat projects.  We thank the many students in the Zoology Department,SIUC, who have helped in the field.  We also thank the members of the Illinois NativePlant Society who provided information on the location of woodrat sign at Fountain Bluffand Little Grand Canyon.LITERATURE CITEDBaskett, C. F.  1925.  The Devonian strata of the Alto Pass Quadrangle. Trans. Illinois Acad.Sci. 18:360-368.Birch, G. L., G. A. Feldhamer, and W. G. Dyer.  1994.  Helminths of the gastrointestinal tractof raccoons in southern Illinois with management implications of Baylisascaris  procyonisoccurrence. Trans. Illinois Acad. Sci. 87:165-170.Crim, J. A.  1961.  The habitat of the woodrat in southern Illinois. M.A. Thesis, SouthernIllinois University, Carbondale.  99 pp.Hall, E. R.  1955.  Handbook of mammals of Kansas. Misc. Publ. Mus. Nat. Hist., Univ.Kansas, 7:1-303.Hall, E. R.  1981.  The mammals of North America. 2nd ed. 2 vols. John Wiley and Sons, NY.1181 pp.Herkert, J. R., ed.  1992.  Endangered and threatened species of Illinois: status and distribution.Vol. 2: Animals. Illinois Endangered Species Protection Board, Springfield.  142 pp.Kazacos, K. R., W. L. Wirtz, and P. P. Burger.  1981.  Raccoon ascarid larvae as a cause of fatalcentral nervous system disease in subhuman primates. J. Am. Vet. Med. Assoc. 179:1089-1094.Kazacos, K. R. and W. M. Boyce.  1989.  Baylisascaris larva migrans. J. Am. Vet. Med. Assoc.195:894-903.Nawrot, J. R.  1974.  The southern Illinois woodrat: an endangered species. M.S. Thesis,Southern Illinois University, Carbondale.  101 pp.Nawrot, J. R. and W. D. Klimstra.  1976.  Present and past distribution of the endangeredsouthern Illinois woodrat (Neotoma floridana illinoensis). Chicago Academy Sci. Nat. Hist.Misc. No. 196.  12 pp.Poor, R. S.  1925.  The character and significance of the basal conglomerate of thePennsylvanian System in southern Illinois. Trans. Illinois Acad. Sci. 18:369-375.Weller, J. M. and G. E. Ekblaw.  1940.  Preliminary geological map of parts of the Alto Pass,Jonesboro, and Thebes Quadrangle. Illinois Geol. Surv. Rep. Invest., No. 70.  26 pp.  West, K. A.  1986.  Illinois eastern woodrat population survey report. Illinois EndangeredSpecies Protection Board, Springfield.  18 pp.Wiley, R. W.  1980.  Neotoma floridana. Mammalian Species, No. 139. 7 pp.Woodrat Recovery Workshop.  1993.  The Allegheny woodrat: where now and where next?Conference held 19-20 March, Dickinson College/ Pennsylvania Biological Survey.47Table 1. Age and sex distribution of woodrats captured at Pine Hills, Union County,July, 1993 - August, 1994.                                                                                                                                                                                    Male Female Total                                                                                                                                                                                                                                                                               Juvenile 14 15 29Subadult 13 25 38Adult 27 41 68                                                                                                                                                                                                                                                                               Total 54 81 135Table 2. Age and sex distribution of woodrats captured at Fountain Bluff, JacksonCounty, January, 1994 - July, 1994.                                                                                                                                                                                    Male Female Total                                                                                                                                                                                                                                                                               Juvenile 2 2 4Subadult 1 4 5Adult 4 6 10                                                                                                                                                                                                                                                                               Total 7 12 19

Recently Discovered Populations of Eastern Woodrats (\u3ci\u3eNeotoma floridana\u3c/i\u3e) in Southern Illinois

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Recently Discovered Populations of Eastern Woodrats (\u3ci\u3eNeotoma floridana\u3c/i\u3e) in Southern Illinois

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