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p m r- r-' ME FYF-11 - - T r r.- 1. 4,6*. of the FLORIDA MUSEUM OF NATURAL HISTORY THE COMPARATIVE ECOLOGY OF BOBCAT, BLACK BEAR, AND FLORIDA PANTHER IN SOUTH FLORIDA David Steffen Maehr Volume 40, No. 1, pf 1-176 1997 == 46 1ms 34 i " 4 '· 0?1~ I. Al' Ai: *'%, R' I.' I / Em/-.Ail-%- .1/9" . -_____- UNIVERSITY OF FLORIDA GAINESVILLE Numbers of the BULLETIN OF THE FLORIDA MUSEUM OF NATURAL HISTORY am published at irregular intervals Volumes contain about 300 pages and are not necessarily completed in any one calendar year. JOHN F. EISENBERG, EDITOR RICHARD FRANZ CO-EDIWR RHODA J. BRYANT, A£ANAGING EMOR Communications concerning purchase or exchange of the publications and all manuscripts should be addressed to: Managing Editor. Bulletin; Florida Museum of Natural Histoty, University of Florida P. O. Box 117800, Gainesville FL 32611-7800; US.A This journal is printed on recycled paper. ISSN: 0071-6154 CODEN: BF 5BAS Publication date: October 1, 1997 Price: $ 10.00 Frontispiece: Female Florida panther #32 treed by hounds in a laurel oak at the site of her first capture on the Florida Panther National Wildlife Refuge in central Collier County, 3 February 1989. Photograph by David S. Maehr. THE COMPARATIVE ECOLOGY OF BOBCAT, BLACK BEAR, AND FLORIDA PANTHER IN SOUTH FLORIDA David Steffen Maehri ABSTRACT Comparisons of food habits, habitat use, and movements revealed a low probability for competitive interactions among bobcat (Lynx ndia). Florida panther (Puma concotor cooi 1 and black bear (Urns amencanus) in South Florida. All three species preferred upland forests but ©onsumed different foods and utilized the landscape in ways that resulted in ecological separation. Further, panthers exhibited crepuscular activity whereas black bears were predominantly diurnal. Diet, movernents, and reproduction varied seasonally among speciel Subadults of all three species demonstrated extensive dispersal abilities, but only male black bears were documented to have crossed the Caloosahatchee River, a potential landscape barrier that may restrict effective dispersal northward in bobcats and panthem BecAllte bobcat and black bear in South Florida occur at relatively high densities. anthropogenic changes to thclandscape and sea level rise willaffect them less severely thanpanther. The problems associated with the habitation of a naturally fragmented and patchy forest are exacerbated by the conversion ofproductive habitat types to types that amavoided. Another factor'' - ' '' ' "'yofcoological relations among this carnivore community is the range ell:adon ofthc coyote (Cani, latians) into South Florida. This canid is known to exhibit interference competition with bobcats, black bears, and panthers in other parts of North America. The diet ofthe coyote in Florida may overlap with the dicts of the three native carnivores by at least 38 percent and asmuch as 64 percent The highest concentrations of black bears and panthers in South Florida Loincide with an extensive forest, a landscape feature that accounts for only a small proportion of public land. Increasing forest fragmentation from the Sarasota area southeastward suggests that most public lands are relatively unimportant to the two larger species Because the demographics of even the.mallest ofthese populations (panther) are shown to be typical of healthy populations, creative management, such as flexible reserve boundaries and the enlistment ofprivate property owners in conservation efforts, may be of more immediate value than symptom-oriented management practices such as genetic introgression. RESUMO Comparagaes do habito alimentar, uso de habitat e movimentos revelaram uma bain probabilidade de interaf6es competitivas entre o «bobcat"(Lynx ndiu), o puma americano (Puma concolor cood, e o urso negro (Urms amencanus) no sul da Florida. As tr68 cap6cies preferiram florestas de tcrras altas mas consumiram diferentes tipos de alimento e utilizaram o espa90 de uma modo que regultou em separa40 =016gica. 0 puma Boresentou atividades crepusculares, enquanto que o urso· negro fbi predominantemente de habito diurno. Dieta, movimentos, e reprodu#o variaram sasonalmente entre as espkies. Subadultos das ' The author & Assistant Professor, Foresuy, C - _ - -- ' '„Lecington KY 40546-0073 U.SA MAEHR, D.S. 1997. The comparative ecology ofbobcat. black bear, and Florida panther in South Florida Bull. Florida Mus. Nat. Hist. 40(1):1-176. 2 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL 40(1) trBs esp6cies demonstraram grande habilidade de dispersao, mas somente machos do uno negro foram documentados atravessando o Rio Caloosahatchee, unia potencial bamira na paisagem que talvez'limite uma dispesao efetiva pan o norte em "bobcals"e purnai Uma vez que no sul da Florida "bobcats" e ursos negros ocorrem em densidades relativame~e altas, mudangas antr6picas na paisagem, somadas a um possivel aumento no nivel das mards. irao afeta-los de maneira menos severa doquc o puma. Os problemas associados com a habits* dedreas naturalmente fragmen,9,1.. e florestas isoladas sao exacerbados pela conversao de habitas produtivos para tipos habitas que sao evitados por cssas ess,6cies. Outro fator queameagaaestabilidade das relag6cs cool6gicas entre esta comunidade de carnivoros 6 a expansao da distribui~ao do coyote (Cani, latrans) que vem ovorrendo no sul da Florida. £ sabido que esse canideo compete com "bobcats" ursos c pumss em outras parts (la An*ica do Norte. A dieta do coyote na F16rida talvez se sobreponha com a dieta desses tres carnivoros natives em pelo menos 38% podendo chegar a16 a 6404 Incais de alta concentragao de urses negrosepumas no gui da F16rida coincidem com florestas extenvas, uma caracteristica de paisagem que ocorrem em pequena proporgao em terms pOblicas. 0 mini%to da fragmentafao das florestas na drea de Sarasota em diregao sul, sugere que a maioria das terras pablicas sao relativamente menos importantes para as duas csp6cics maiores. Devido aos fatores demogr~ficos at,1 para a menor dessas popula~es (punia) se mostrarem ser tipicos de popula0es sadias, o mancio criativo. tais como limits mais fiexiveis das reservas, e o cadastramento de proprietdrios de terras privadas em esforfos conservacionistas, talvcz tenham valor mais imediato do que pdticas de manejo sintomdticas, como por exemplo introgressao genatica. TABLE OF CONTENTS Acknowledgemmk 3 1. Introduction........................................................................................................................................... Overview ofCamivore Community Studies.................................................................................. - Study A- 9 Summary of Previous Large Carnivore Work in Florida 13 General Methodology 18 2. Dietary Overi,r 21 Methods................................................,..............„........,................................................................. 21 Results and Discussioa................................................................................................................ 22 Species Compari- 27 =*ASS= 3. Habitat Use Among South Florida's Large Mammalian Carnivores. ..........'........~.........~...........~........ Mel]¤Is........................................................................................................................................... Results and Discussion.................................................................................................................... 4. Habilat Pattern around Florida Panther Natal Dens and Black Bear Winter Dem............................. Method. Results and Discussion..............................„......„.......„........................................,......................... Influence of Roark 65 5. Home Range, Activity, and Land Tenure 73 Methods 74 Results and Discussion. 75 Seasonal Effects 76 Home Range Fidelity and Replacement 81 Overlap Within and Among Rperi- 83 6. Dispersal Characteridie« 117 118 Results and Discussion...................................................,*............................................................... 118 Adults and Dispersers Compared............................................................................................... 120 7. Synthesis and Conclusions................................................................................................................... 144 The Rellim of Wild Canids to Florida......... .. .......................................................... 147 A Longer Range View 150 Literature Cited......................................................................................·········································· 161 Appendix A. .................I.-M-....*..........*.............A.............."..m...."m...................~....'....................'.......... 173 Appendix B. ......~.. --m.-I~~eee~~,m.. -le-m-g---*mil-Mm~Mm-mM--m#-m-----I-'-Immmm. 175 MAEHR: ECOLOGY BOBCAT, BLACK BEAR, PANTHER 3 ACKNOWLEDGEMENTS Many people have contributed to our current understanding of large carnivore ecology in South Florida. Notable in this endeavor are E.D. Land, Todd Logan, J.C. Roof J.W. McCown, O.L Bass, and J.N. Layne. R.T. McBride. and frequently his sons Rocky and Rowdy, linked its with study in;„,i# and maintained long-term contact with many ofthem. I amalsogratefulfortheopportunity tohave woked with M.E. Roelke, C. Glass, M.Lamm, T. Ruth, S. Citino, and especially J. Lanier, all of whom helped to look after anesthetized bobcats and panthers. J. Kappes, R. Bell, and P. Baronoff were important field assistants who lent their unique