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Prey Records for the Eastern Indigo Snake (Drymarchon couperi)
Dirk J. Stevenson, M. Rebecca Bolt, Daniel J. Smith, Kevin M. Enge, Natalie L. Hyslop, Terry M. Norton, and Karen J. Dyer

Southeastern Naturalist, Volume 9, Issue 1 (2010): 1–18

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2010 SOUTHEASTERN NATURALIST 9(1):1–18 Prey Records for the Eastern Indigo Snake (Drymarchon couperi) Dirk J. Stevenson1,*, M. Rebecca Bolt2, Daniel J. Smith3, Kevin M. Enge4, Natalie L. Hyslop5,6, Terry M. Norton7,8, and Karen J. Dyer9 Abstract - Prey items for the federally protected Eastern Indigo Snake (Drymarchon couperi) were compiled from published and gray literature, field observations, necropsies, dissection of museum specimens, and personal communications from reliable sources. One hundred and eighty-six records were obtained for 48 different prey species. Anurans, Gopher Tortoises, snakes, and rodents comprised ca. 85% of the prey items. Most records (n = 143) that mentioned size were from adult indigos; 17 were from juveniles. Prey records were collected from 1940–2008 and were available for all months of the year. These data confirm that Eastern Indigo Snakes eat a wide assortment of prey of varying sizes. This strategy allows D. couperi to potentially forage successfully in many different types of habitats and under fl uctuating environmental conditions, a valuable trait for a top-level predator that requires a large home range. Introduction Drymarchon couperi Holbrook (Eastern Indigo Snake), with a maximum recorded total length of 2629 mm, is one of the largest snakes in North America (Conant and Collins 1991). It has been federally listed as Threatened since 1978 under the Endangered Species Act (US Fish and Wildlife Service 1978). Drymarchon couperi is diurnal and mostly terrestrial (Layne and Steiner 1996, US Fish and Wildlife Service 2008). Of the two main hunting strategies employed by snakes (ambush predator vs. active forager; see Mushinsky 1987), D. couperi is generally regarded as a wide-ranging, active forager (Hyslop 2007, Landers and Speake 1980, Moler 1992, Smith and Voigt 2005). In portions of its range, D. couperi spends the cooler seasons (November–March) in xeric upland habitats such as Pinus palustris Miller (Longleaf Pine)-Aristida stricta Michaux (Wiregrass) sandhills, where individuals frequently shelter in Gopherus polyphemus (Daudin) (Gopher Tortoise) burrows (Hyslop et al. 2009a, Stevenson et al. 2009). During 1Project Orianne, Ltd., Indigo Snake Initiative, 414 Club Drive, Hinesville, GA 31313. 2Dynamac Corporation, Mail Code DYN-5, John F. Kennedy Space Center, FL 32899. 3Department of Biology, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816. 4Florida Fish and Wildlife Conservation Commission, 1105 SW Williston Road, Gainesville, FL 32601. 5Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602. 6Present address - Department of Wildlife Ecology, University of Florida, 324 Newins-Ziegler Hall, Gainesville, FL 32611. 7St. Catherines Island Foundation, 182 Camelia Road, Midway, GA 31320. 8Present address - Georgia Sea Turtle Center, 214 Stable Road, Jekyll Island, GA 31527. 9Audubon’s Tavernier Science Center, 115 Indian Mound Trail, Tavernier, FL 33070. *Corresponding author - dstevenson@projectorianne.org. 2 Southeastern Naturalist Vol. 9, No. 1 the warmer months (April–October), these snakes may move considerable distances to lower and wetter habitats such as mesic pine fl atwoods, hydric hammocks, or hardwood swamps (Breininger et al. 2004, Hyslop 2007, Smith and Voigt 2005, Speake et al. 1978). Drymarchon couperi forage in a variety of habitats and have been observed sticking their heads into stump holes and burrows, patrolling the margins of wetlands, prowling thickets and brush piles, investigating rodent nests and burrows, and climbing in pursuit of Pantherophis alleghaniensis (Say) (Rat Snake) (Hyslop 2007; Layne and Steiner 1996; P. Moler, Gainesville, FL, pers. comm.; A. Nielson, Punta Gorda, FL, pers. comm.; D.J. Smith, 2009 unpubl. data). Drymarchon couperi is not a constrictor; prey is approached rapidly and swallowed alive or immobilized/killed by the muscular chewing motions of the predator snake (Keegan 1944, Moulis 1976). We conducted the current study to bring together all available information regarding the diet of D. couperi in an attempt to answer the following questions: What types of prey are preferred? During what seasons/months does D. couperi forage? Methods We compiled D. couperi prey records based on 1) a comprehensive review of the published literature and technical reports, including the results of recent D. couperi studies we conducted in Georgia (Hyslop 2007; Norton et al. 2004; Stevenson et al. 2003, 2009) and Florida (Breininger et al. 2004, Smith and Voigt 2005) (n = 115 records); 2) our personal observations (n = 27 records); 3) dissection of museum specimens housed at the herpetological collections of Georgia Southern University, Statesboro, GA (formerly the Savannah Science Museum Collection [Williamson and Moulis 1994]) (n = 12 records); the University of Florida Museum of Natural History, Gainesville, FL (n = 2); and the University of Central Florida, Orlando, FL (n = 5 records); and 4) interviews with experienced field biologists, commercial or recreational snake hunters, and local residents who lived on sites inhabited by D. couperi (n = 26 records). We compiled prey records for wild D. couperi only, and included prey records of radio-transmittered D. couperi released and tracked at their original capture sites following transmitter implantations (Hyslop 2007, Smith and Voigt 2005) and juveniles hatched and raised in captivity before being released (Smith 1987). When data were available, we listed the date, size (snout–vent length [SVL] or total length [TL] in mm), and sex of the corresponding D. couperi for each prey record, and the literature citation or name of the individual from which the record is based. Additionally, we characterized each prey record as follows: examination of feces of captured individuals held briefl y in the laboratory (F); dissection from a necropsied specimen or from a museum specimen (N); observation from the field (O); regurgitated by or palpated from a snake (R); or unknown (U). We classified D. couperi less than 1000 mm TL as juveniles, and snakes ≥1000 mm as adults. We treated those records where 2010 D.J. Stevenson et al. 3 multiple eggs (e.g., a clutch of turtle or bird eggs) were recovered from the same D. couperi on the same date as a single prey record. We determined proportions for the four major prey types (Anurans, Gopher Tortoises, snakes, and small mammals), and calculated 95% confi- dence limits (Beyers et al. 1984). We subdivided the D. couperi prey record data into three categories: 1) males and females, 2) juveniles and adults, and 3) Georgia snakes and Florida snakes. Results We compiled 185 separate vertebrate prey records for D. couperi totaling 47 species: 1 fish, 1 salamander, 3 anuran, 1 crocodilian, 3 turtle, 1 lizard, 24 snake, 4 bird, and 9 mammal species (Appendix 1). Anurans, Gopher Tortoises, snakes, and rodents accounted for 158 (85.4 %) of these records, with snakes accounting for 91 (49.2 %) of the records. Ten of the 41 (24.4 %) specimens we necropsied or dissected contained prey. Table 1 provides the proportions of the four major prey types for D. couperi by sex (males and females), size (juveniles and adults), and state (Georgia snakes and Florida snakes). Invertebrate prey records (n = 10), many of which probably represent secondary ingestion, were limited to one slug and insects (beetles, caterpillars, unidentified insects). These prey records include three instances of carrionfeeding by D. couperi (shark [Chondrichthyes], Lithobates sphenocephalus Cope [Southern Leopard Frog], and Pantherophis guttatus (L.) [Red Cornsnake]). A minimum of 16 individual D. couperi contained multiple prey items. Specific size of the predator D. couperi was available for 72 individuals (6 juveniles, 66 adults) and an additional 49 snakes were recorded as adults without being measured; 160 prey records were available for these snakes (Fig. 1). Prey documented for juvenile D. couperi included a Anaxyrus terrestris (Bonnaterre) (Southern Toad), two Glass Lizards (Ophisaurus sp.), a Thamnophis sauritus (L.) (Eastern Ribbonsnake), a Cemophora coccinea (Blumenbach) (Scarletsnake), a Diadophis punctatus (L.) (Ring-necked Snake), a Red Cornsnake, seven Sistrurus miliarius (L.) (Pigmy Rattlesnake), a juvenile D. couperi, and the aforementioned slug and insects. The distribution of prey records per month (Fig. 2) was: 6 (January), 3 (February), 2 (March), 2 (April), 7 (May); 9 (June), 9 (July), 5 (August), 4 (September), 9 (October), 10 (November), and 4 (December). Discussion This review reinforces prior conclusions from other researchers that D. couperi is a eurytrophic species (Layne and Steiner 1996, Moler 1992). Our study corroborates the findings of Landers and Speake (1980), who reported that D. couperi preys primarily on amphibians, small Gopher Tortoises, snakes, and small mammals. The diverse food habits of D. couperi, combined with its high vagility (Breininger et al. 2004, Hyslop 2007, Smith and Voigt 2005, Speake et al. 1978), allow individuals to forage successfully in a wide variety of habitats (xeric pinelands, scrub, fl atwoods, hydric 4 Southeastern Naturalist Vol. 9, No. 1 hammocks, wetlands, and disturbed landscapes such as ditch banks within sugarcane plantations, agricultural fields, and suburban neighborhoods) and may enable populations to endure the effects of adverse environmental conditions (e.g., droughts, see Stevenson et al. 2003). In addition to frequently moving between habitats, D. couperi have among the largest home ranges of any North American snake (ca. 809–1214 ha [2000–3000 ac] for some Georgia males; Hyslop 2007, Layne and Steiner 1996, Speake et al. 1978). Our only documented fish-predation event by D. couperi was one instance of carrion-feeding on a shark. We also located a single instance of Table 1. Proportions (P) and lower (LCL) and upper (UCL) 95% confidence limits for major prey types for Eastern Indigo Snakes categorized by sex, age, and location. Anurans Gopher tortoises Snakes Small mammals P LCL UCL P LCL UCL P LCL UCL P LCL UCL Males 0.17 0.13 0.21 0.20 0.15 0.24 0.54 0.48 0.59 0.10 0.07 0.13 Females 0.13 0.09 0.16 0.06 0.04 0.09 0.69 0.64 0.74 0.13 0.09 0.16 Juveniles 0.07 0.06 0.09 0.00 0.00 0.00 0.86 0.84 0.88 0.07 0.06 0.09 Adults 0.15 0.13 0.17 0.17 0.14 0.19 0.50 0.47 0.53 0.19 0.16 0.21 Georgia 0.16 0.12 0.20 0.24 0.20 0.28 0.52 0.47 0.57 0.08 0.05 0.11 Florida 0.17 0.13 0.21 0.08 0.05 0.10 0.56 0.51 0.60 0.20 0.16 0.24 Figure 1. Prey records for juvenile (n = 17 records) and adult (n = 143 records) Eastern Indigo Snakes (Drymarchon couperi). 2010 D.J. Stevenson et al. 5 D. couperi preying on a salamander. However, captive D. couperi readily consume live Carassius auratus (L.) (Goldfish), minnows (Cyprinidae), and dead mullet (Mugilidae) (D. Alessandrini, Cincinnati, OH, pers. comm.; V. Johnson, Auburn, AL, pers. comm.), and we suspect that wild snakes forage in seasonal “dry-downs” where receding water levels concentrate fishes, amphibians, and other vertebrate prey. Lizards are also poorly represented in our summary data (Appendix 1). This result could be an artifact of the dataset, as several species of lizards including Anolis carolinensis Voigt (Green Anole), Pleistiodon (= Eumeces) laticeps (Schneider) (Broadhead Skink), Pleistiodon (= Eumeces) inexpectatus Taylor (Southeastern Five-lined Skink), Ophisaurus ventralis (L.) (Eastern Glass Lizard) and Ophisaurus attenuatus Cope (Slender Glass Lizard) that commonly occur sympatrically with D. couperi are readily consumed by wild-caught captive adults and their hatchlings (Moulis 1976, Williamson and Moulis 1979; V. Johnson, pers. comm.). We believe, however, that D. couperi are seldom successful in capturing fast-moving, secretive, and/or arboreal lizards (e.g., Aspidocelis sexlineata (L.) [Six-lined Racerunner], Plestiodon [= Eumeces] spp. [toothy skinks]) under natural conditions, and the small size of many lizards makes it energetically costly to pursue them. Our review indicates that D. couperi is capable of subduing and eating sizeable prey, including Crotalus spp. (rattlesnakes) up to ca. 1000 mm TL and adult Sigmodon hispidus Say and Ord (Hispid Cotton Rat), and that Figure 2. Monthly distribution of prey records (n = 70) for Eastern Indigo Snakes (Drymarchon couperi). 6 Southeastern Naturalist Vol. 9, No. 1 multiple food items are often eaten within a short period of time. In Guatemala, a Drymarchon melanurus (Boie) (Black-tailed Indigo Snake) that was 2950 mm TL was observed swallowing a 1683-mm TL Boa constrictor L. (Boa Constrictor); this same individual also contained a 953-mm TL Atropoides nummifer (Rüppell) (Jumping Viper) (Duellman 1963). Conversely, large D. couperi may sometimes consume fairly small prey items relative to their size. For example, the stomach of a 1637-mm TL adult male D. couperi from Long County, GA, contained a hatchling Red Cornsnake (ca. 250 mm TL). The observation of a large male D. couperi that fed repeatedly on Pipilo erythrophthalmus (L.) (Eastern Towhee), (R. Ashton, Newberry, FL, pers. comm.; see Appendix 1) is noteworthy. On three occasions, Ashton observed this snake lying motionless on the ground near a small artificial pond, where it successfully ambushed Eastern Towhees when they came to bathe. The diet of hatchling and juvenile D. couperi in the wild remains poorly known. Layne and Steiner (1996) mention that insects were the only food items in stomachs of three juveniles ranging from 493 to 591 mm TL. From the limited number of records that we report herein, it does appear that juvenile D. couperi, similar to adults, often feed on snakes. Additional sympatric prey species (i.e., not listed in Appendix 1) that were consumed by young D. couperi (captive hatched from wild-caught females) included tadpoles of the Southern Leopard Frog, Scaphiopus holbrookii (Harlan) (Eastern Spadefoot), and a number of snakes including the Regina rigida (Say) (Glossy Crayfish Snake) and Lampropeltis triangulum (Holbrook) (Scarlet Kingsnake) (Moulis 1976; V. Johnson, pers. comm.). Young D. couperi grow rapidly, reaching 1250–1450 mm TL by their second winter (Stevenson et al. 2009) and presumably feed often to meet energy requirements. Clearly, D. couperi are strongly ophiophagous, and the frequency of cannibalism in wild populations merits further study. As documented for Georgia and some Florida locations, D. couperi of various size classes concentrate seasonally in the same xeric upland habitats, potentially utilizing the same Gopher Tortoise burrows (Hyslop et al. 2009a, Smith and Voigt 2005, Stevenson et al. 2009). In addition to the instance of cannibalism listed in Appendix 1, Smith (1987) documented cannibalism at her northern Florida study site, where a yearling D. couperi was consumed by a larger yearling. Drymarchon couperi were observed feeding, or prey items were documented, during every month of the year. The eleven instances that occurred in January–March were all from Florida. Snakes in the northern part of the range (southern Georgia) restrict their above-ground movements and foraging during January–February when low temperatures (nighttime lows of -4 to +4 ºC, daytime highs of 13 to 18 ºC) are common (Hyslop 2007; D.J. Stevenson, unpubl. data). Adult female D. couperi annually lay clutches of 4–14 eggs (Hyslop et al. 2009b; Moulis 1976; V. Johnson, pers. comm.) during the spring. We documented only a single instance of an adult female D. couperi feeding during the winter (Appendix 1), suggesting that gravid females may limit food intake prior to oviposition. Our study indicates that D. couperi is a predator of a wide diversity of animals, including invertebrates, fish, anurans, salamanders, small crocodilians, 2010 D.J. Stevenson et al. 7 turtles, lizards, snakes—including venomous species—birds, mammals, and the eggs of vertebrates. Although certainly not dietary specialists per se, small turtles (including young Gopher Tortoises), anurans, rodents, and snakes figure prominently in the diet of wild D. couperi. Where their ranges overlap, burrows of the Gopher Tortoise are likely important to the foraging ecology of D. couperi; of the prey species we compiled, the Southern Toad, Gopher Tortoise, Coluber fl agellum (Shaw) (Eastern Coachwhip), Heterodon platirhinos Latreille (Eastern Hog-nosed Snake), and Crotalus adamanteus (Palisot de Beauvois) (Eastern Diamondbacked Rattlesnake) are known to frequently shelter in tortoise burrows (Jackson and Milstrey 1989; D.J. Stevenson, unpublished data.). Thus, at sites where D. couperi inhabits upland pineland ecosystems (e.g., sandhills, pine fl atwoods and scrubs), it is vital to employ the appropriate habitat management or restoration techniques (e.g., prescribed fire, mechanical or herbicide thinning of hardwoods, etc.) that foster the open-canopied, grassy Longleaf Pine environs preferred by Gopher Tortoises and D. couperi (Landers and Speake 1980, Hyslop et al. 2009a, Means 2006). Because adult D. couperi have large home ranges, often travel between upland and wetland habitats, and commonly prey on upland species (e.g., Eastern Coachwhip, Gopher Tortoise) as well as wetland species (ranid frogs, aquatic snakes), our study underscores the importance of large contiguous tracts that contain both upland and wetland habitats connected by intact habitat corridors to the conservation of D. couperi. Acknowledgments For contributing their unpublished observations on eastern indigo snake prey items, we thank F. Antonio, R. Ashton, D. Breininger, B. Cope, J. Emanuel, A. Flanagan, S. Godley, H. Kale, K. Krysko, J. Layne, M. Legare, B. McGighan, P. Moody, K. Morin, R. Moulis, A. Nielson, D. Pearson, R. Redmond, C. Schmittler, M. Smith, R. Van Nostrand, J. Watt, and C. Webb. For general support and assistance, we thank D. Alessandrini, M. Barnwell, L. Carlile, J. Jensen, L. McBrayer, P. Moler, K. Ravenscroft, A. Safer, E. Shackleton, F. Snow, M. Wallace, M. Welker, and B. Willis-Stevenson. We thank E. Stolen for his statistical expertise and C. Jenkins for reviewing the manuscript. Literature Cited Alvarez, K. 1996. Indigo snake preys on marsh rabbit. Florida Department of Environmental Protection Resource Management Notes 8(2):37. Babis, W.A. 1949. Notes on the food of the indigo snake. Copeia 1949(2):147. Becker, C. 1997. Indigo notes. Florida Department of Environmental Protection, Florida Park Service Resource Management Notes 9(2):22–23. Belson, M.S. 2000. Drymarchon corais couperi (Eastern Indigo Snake) and Micrurus fulvius fulvius (Eastern Coral Snake): Predator-prey. Herpetological Review 31(2):105. Beyers, C.R., and R.K. Steinhorst. 1984. Clarification of a technique for analysis of utilization-availability data. Journal of Wildlife Management 48:1050–1054. 8 Southeastern Naturalist Vol. 9, No. 1 Breininger, D.R., M.L. Legare, and R.B. Smith (Bolt). 2004. Eastern Indigo Snakes (Drymarchon couperi) in Florida: Infl uence of edge effects on population viability. Pp. 299–311, In H. Akcakaya, M. Burgman, O. Kindvall, C. Wood, P. Sjögren-Gulve, J. Hatfield, and M. McCarthy (Eds.). Species Conservation and Management: Case Studies. Oxford University Press, New York, NY. Carr, A.E., Jr. 1940. A Contribution to the Herpetology of Florida. University of Florida Publications, Biological Science Series: Volume III, No. 1. Gainesville, FL. Conant, R., and J.T. Collins 1991. Reptiles and Amphibians of Eastern and Central North America. Houghton Miffl in Company, New York, NY. 450 pp. Dilley, W.E., 1954. Indigo snakes versus Flat-tailed Water Snake. Everglades Natural History 2:48. Dodd, C.K., Jr. and W.J. Barichivich. 2007. Movements of large snakes (Drymarchon, Masticophis) in north-central Florida. Florida Scientist 70:83–94. Duellman, W.E. 1963. Amphibians and reptiles of the rainforests of southern El Petán, Guatemala. University of Kansas Museum of Natural History Publications 15(5):205–249. Hopkins, M.N., Jr. 2001. In One Place: The Natural History of a Georgia Farmer. Saltmarsh Press, St. Simon’s Island, GA. 265 pp. Hyslop, N.L. 2007. Movements, habitat use, and survival of the threatened Eastern Indigo Snake (Drymarchon couperi) in Georgia. Unpublished PhD Dissertation. University of Georgia, Athens, GA. 132 pp. Hyslop, N.L., R.J. Cooper, and J.M. Meyers. 2009a. Seasonal shifts in shelter and microhabitat use of the threatened Eastern Indigo Snake (Drymarchon couperi) in Georgia. Copeia 2009(3):460–466. Hyslop, N.L., J.M. Meyers, R.J. Cooper, and T.M. Norton. 2009b. Survival of radioimplanted Eastern Indigo Snakes (Drymarchon couperi) in relation to body size and sex. Herpetologica 65(2):199–206. Jackson, D.R., and E.G. Milstrey. 1989. The fauna of Gopher Tortoise burrows. Pp. 86–98, In J.E. Diemer, D.R. Jackson, J.L. Landers, J.N. Layne, and D.A. Wood (Eds.). 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Moler (Ed.). Rare and Endangered Biota of Florida, Volume 3, Amphibians and Reptiles. University Press of Florida, Gainesville, FL. 291 pp. Moulis, R. 1976. Autecology of the Eastern Indigo Snake, Drymarchon corais couperi. Bulletin of the New York Herpetological Society, Vol.12 No. 3 and 4. Mount, R.H. 1975. The Reptiles and Amphibians of Alabama. Auburn University Experimental Station, Auburn, AL. Mumme, R.L. 1987. Eastern Indigo Snake preys on juvenile scrub jay. Florida Field Naturalist 15:53–54. 2010 D.J. Stevenson et al. 9 Mushinsky, H.R. 1987. Foraging ecology. Pp. 302–334, In R.A. Seigel, J.T. Collins, and S.S. Novak (Eds.). Snakes: Ecology and Evolutionary Biology. Macmillan Publishing, New York, NY. Neill, W.T. 1964. Taxonomy, natural history, and zoogeography of the Rainbow Snake. Farancia erytrogramma (Palisot de Beauvois). American Midland Naturalist 71(2):257–295. Norton, T.M., R. Poppenga, N. Stedman, D. Stevenson, T. Chen, M. Oliva, M. Mitchell, E. Jacobson, E. 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Survey and monitoring of the Eastern Indigo Snake in Georgia. Southeastern Naturalist 2:393–408. Stevenson, D.J., K.M. Enge, L.D. Carlile, K.J. Dyer, T.M. Norton, N.L. Hyslop, and R.A. Kiltie. 2009.. An Eastern Indigo Snake (Drymarchon couperi) markrecapture study in southeastern Georgia. Herpetological Conservation and Biology: 4:30–42. Timmerman, W.W. 1995. Home range, habitat use, and behavior of the Eastern Diamondback Rattlesnake (Crotalus adamanteus) on the Ordway Preserve. Bulleting of the Florida Museum of Natural History 38, Part 1(5):127–158. US Fish and Wildlife Service. 1978. Endangered and Threatened Wildlife and Plants. Listing of the Eastern Indigo Snake as a threatened species. Federal Register 43:4026–4029. US Fish and Wildlife Service. 2008. Eastern Indigo Snake (Drymarchon couperi): 5-Year Review-Summary and Evaluation. Mississippi Ecological Services Field Office, Jackson, MS. 30 pp. Williamson, G.K., and R.A. Moulis. 1994. Herpetological Specimens in the Savannah Science Museum Collection: Volume 2—Reptiles. Savannah Science Museum Special Publication No. 2. Savannah, GA. 418 pp. 10 Southeastern Naturalist Vol. 9, No. 1 Appendix 1. Eastern Indigo Snake (Drymarchon couperi) prey records with corresponding details for each occurrence. Indigos <1000 were classified as juveniles and ≥1000 were classified as adults. # = number of occurrences, So = source, Size = size of Drymarchon (mm), Sex = sex of Drymarchon. Source: R = regurgitated or palpated, N = dissected from a necropsied specimen or from a museum specimen, F = feces, and O = field observation. Size: TL = total length, SVL = snout–vent length. DOR = road mortality. Specimens from university herpetology collections: UF = University of Florida, GSU = Georgia Southern University, and UCF = University of Central Florida. Prey items # So State Observer/ citation Size Sex Date Notes on Prey Invertebrates Gastropoda Stylommatophora: Philomycidae Slug (Philomycus sp.); 75 mm TL 1 R FL Rossi and Lewis (1994) 610 mm TL 17 May 1993 Insecta Insects 6 N,F FL Layne and Steiner (1996) Adults Insects present in 6 of 54 adults Insects 3 N,F FL Layne and Steiner (1996) 493 - 591 mm TL Insects present in of 3 of 4 juveniles Vertebrates Chondrichthyes Unidentified shark; head only, dead 1 O FL Smith and Antonio (2007) ca. 2000 mm TL 18 Mar 2001 Amphibia Anura: Bufonidae Southern Toad (Anaxyrus terrestris 1 O FL R. Bolt 1320 mm TL m July 1998 (Bonnaterre)) Southern Toad; adult 1 R GA D. Stevenson 1305 mm SVL m 25 Nov 2003 Also contained Eastern Garter Snake Southern Toad; adult 1 N FL Layne and Steiner (1996) Southern Toads; adults 3 N FL Layne and Steiner (1996) Adult All from same indigo Southern Toad; adult 1 N GA D. Stevenson 1426 mm SVL m 10 Oct 2001 Also contained Southern Copperhead Southern Toad; adult 1 R GA N. Hyslop Adult m 23 Jul 2004 Also regurgitated adult Eastern Hog-nosed Snake 2010 D.J. Stevenson et al. 11 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Southern Toad; adult 1 N GA D. Stevenson Adult f 30 Aug 2003 Southern Toad 1 N FL Steiner et al. (1983) Southern Toad 1 N FL K. Krysko 465 mm SVL 11 Sep 2008 UF #153675 Southern Toad 4 N FL R. Bolt 1550 mm TL; 1275 mm SVL Anura: Ranidae American Bullfrog (Lithobates 1 O GA Stevenson et al. (2003) Adult 15 Aug 1998 catesbeianus Shaw); adult Southern Leopard Frog (Lithobates 1 R FL R. Bolt 1520 mm TL f May 2002 sphenocephalus Cope) Southern Leopard Frog 1 N FL K. Krysko 1010 mm SVL 19 Nov 2007 UF #152681 Southern Leopard Frog 1 O GA Hyslop (2007) 2180 mm TL; m 10 Aug 2004 1825 mm SVL Southern Leopard Frog 1 O FL Layne and Steiner (1996) Southern Leopard Frog; dead 1 O FL Layne and Steiner (1996) Ranid frog (Lithobates sp.) 1 O GA Hyslop (2007) 2180 mm TL; m 20 Apr 2004 1825 mm SVL Anura: Unidentified Unidentified anuran 3 N FL Layne and Steiner (1996) Unidentified anuran; large 1 O FL Dodd and Barichivich (2007) 1105 mm SVL m 22 Sep 1986 Unidentified "toad" 1 R GA Mount (1975) 2130 mm TL Also contained hatchling Gopher Tortoise, Southern Hog-nosed, and Pigmy Rattlesnake Caudata: Sirenidae Unidentified sirenid, ca. 140 mm TL 1 O FL J. Emanuel 1067-1219 mmTL 2004 Reptilia Crocodilia: Alligatoridae American Alligator (Alligator 1 O FL R. Van Nostrand Adult mississippiensis (Daudin)); juvenile Testudines: Emydidae Peninsula Cooter (Pseudemys 6 R FL Layne and Steiner (1996) Adult peninsularis (Carr)) eggs 12 Southeastern Naturalist Vol. 9, No. 1 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Florida Red-bellied Cooter U O FL J. Watt 1829 mm TL Eating hatchlings (Pseudemys nelsoni (Carr)); hatchlings emerging from a nest on a turtle farm Testudines: Testudinidae Gopher Tortoise (Gopherus 1 R GA Mount (1975) 2130 mm TL Also contained toad, polyphemus (Daudin)); hatchling Southern Hog-nosed, and Pigmy Rattlesnake Gopher Tortoise; hatchlings 4 R GA Landers and Speake (1980) Adult Gopher Tortoise; all hatchlings or 6 N FL Layne and Steiner (1996) Adults Two tortoises from same small juveniles , egg remains indigo Gopher Tortoise; hatchling 1 N GA Stevenson et al. (2003) 1514 mm SVL f 17 Oct 1997 DOR; also contained Eastern Diamondback; GSU # 97.0494 Gopher Tortoise; juvenile 1 O GA Stevenson et al. (2003) Adult 27 Sep 2000 Gopher Tortoise; hatchling 1 R GA R. Redmond 1778 mm TL; m 16 Dec 2006 1486 mm SVL Gopher Tortoise; juvenile 1 R GA Hyslop (2007) Adult m Oct 2003 Gopher Tortoise; hatchlings 3 N GA Hyslop (2007) 2095 mm TL; m 20 Nov 2003 All from same indigo 1780 mm SVL Gopher Tortoise; juvenile 1 R FL R. Bolt Adult m Nov Gopher Tortoise; juvenile (yearling) 1 O FL S. Godley Adult m Jul 1985 Gopher Tortoise;, juvenile 1 R FL Smith and Voigt (2005) 1680 mm SVL m 7 Dec 2004 Regurgitated following capture for transmitter removal Testudines: Undentified Unidentified turtle eggs 4 N FL Babis (1949) 1828 mm SVL 7 Nov 1948 Eggs averaged 3.0 x 1.3 cm; also contained 2 Pigmy Rattlesnakes Unidentified turtle 1 O FL R. Van Nostrand Adult Squamata: Sauria Sauria: Anguidae Glass Lizard (Ophisaurus sp.) 1 O FL R. Bolt 1350 mm TL f May Glass Lizard 1 R FL Layne and Steiner (1996) 2010 D.J. Stevenson et al. 13 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Glass Lizard 2 F FL Smith (1987) Juveniles 1986 Squamata: Serpentes Serpentes: Colubridae Watersnake (Nerodia sp.) 1 O GA Hyslop (2007) 1765 mm TL; f 10 Jun 2004 1490 mm SVL Brown Watersnake (Nerodia 1 O FL Steiner et al. (1983) 1500 - 1800 mm TL 5 Jan 1982 taxispilota (Holbrook)) Mangrove Saltmarsh Watersnake 1 O FL Dilley (1954) Adult (Nerodia clarkii Kennicott) Southern Watersnake (Nerodia 1 O FL Smith and Voigt (2005) 1650 mm SVL m 24 Jun 2004 fasciata (L.)) Eastern Ribbonsnake (Thamnophis 1 R FL K. Dyer 898 mm TL f 19 May 2003 sauritus (L.)), 890 mm TL Eastern Gartersnake (Thamnophis 1 R GA D. Stevenson 1305 mm SVL m 25 Nov 2003 Also contained Southern sirtalis (L.)); adult Toad Eastern Gartersnake; adult 1 O FL R. Van Nostrand Scarletsnake (Cemophora coccinea) 1 O FL Smith (1987) Juvenile 1986 (Blumenbach)) Ring-necked Snake (Diadophis 1 O FL Smith and Voigt (2005) 1470 mm SVL f 6 Nov 2004 punctatus (L.)) Ring-necked Snake 1 O FL Layne and Steiner (1996) Ring-necked Snake; front half only 1 N FL R. Bolt 545 mm TL; 18 Aug 1994 UCF #0145 445 mm SVL Eastern Hog-nosed Snake (Heterodon 1 R GA N. Hyslop Adult m 23 Jul 2004 Also contained adult platirhinos Latreille); adult Southern Toad Eastern Hog-nosed Snake; adult 1 O GA Hyslop (2007) 1675 mm TL; f 28 Oct 2004 1450 mm SVL Eastern Hog-nosed Snake 1 N FL Layne and Steiner (1996) Southern Hog-nosed Snake 1 R GA Mount (1975) 2130 mm TL (Heterodon simus (L.)) Red-bellied Mudsnake (Farancia 1 O FL R. Bolt 1630 mm TL m Jan abacura (Holbrook)) 14 Southeastern Naturalist Vol. 9, No. 1 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Rainbow Snake (Farancia 1 R FL Neill (1964) 2235 mm TL erytrogramma (Palisot de Beauvois)); adult Common Kingsnake (Lampropeltis 1 O FL P. Moody 1524–1829 mm TL 1996 getula (L.)); ca.1219 mm TL Eastern Coachwhip (Coluber fl agellum 1 R FL Carr (1940) Adult (Shaw)); adult, 1500 mm TL Eastern Coachwhip; adult, 1783 mm TL 1 R FL Layne and Steiner (1996) 2056 mm TL Eastern Coachwhip; adult, 1000 mm TL 1 R FL Layne and Steiner (1996) 1918 mm TL Eastern Coachwhip 1 N FL Layne and Steiner (1996) Eastern Coachwhip; adult 1 O FL Smith and Voigt (2005) 1630 mm SVL m 13 Jun 2004 Eastern Coachwhip; adults, each ca. 2 R GA Hopkins (2001) 1829 mm TL both from same indigo 914 mm TL Eastern Indigo Snake (Drymarchon 1 O FL F. Antonio 1829 mm TL m couperi (Holbrook)); male, ca. 1219 mm TL Eastern Indigo Snake); yearling 1 O FL Smith (1987) juvenile 1986 North American Racer (Coluber 1 O FL Dodd and Barichivich (2007) 1105 mm SVL m 10 Dec 1986 constrictor L.) North American Racer; adult 1 O FL R. Bolt Adult m North American Racer 1 O FL R. Ashton North American Racer 3 N, F2 FL Layne and Steiner (1996) 3 different indigos North American Racer 1 O FL Smith and Voigt (2005) Adult Sep 2004 Observed in residential setting, Zellwood, FL North American Racer; adult, ca. 1 O GA Hyslop (2007) 1860 mm TL; f 18 Jun 2004 967 mm TL 1555 mm SVL North American Racer 1 O GA Hyslop (2007) 1950 mm TL; f 23 Jul 2004 1575 mm SVL North American Racer; 1168 mm TL 1 O FL K. Morin 1524+ mm TL 2001 North American Racer 1 O FL Smith (1987) Adult 1986 Eastern Ratsnake (Pantherophis 1 O FL R. Bolt 1880 mm TL f Jan alleghaniensis (Say)) Eastern Ratsnake 1 R FL R. Bolt 1960 mm TL m Feb Eastern Ratsnake 1 O FL Smith and Voigt (2005) Adult m 22 May 2004 Eastern Ratsnake; adult 1 O FL R. Ashton Adult 2010 D.J. Stevenson et al. 15 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Eastern Ratsnake; adult, ca. 1500 mm TL 1 O FL R. Bolt (pers. comm.) 1680 mm TL m Oct Eastern Ratsnake 1 O FL Becker (1997) 1524–1829 mm TL 8 May 1997 Eastern Ratsnake 1 O GA Hyslop (2007) 1555 mm SVL f 14 May 2004 Eastern Ratsnake; adult, ca. 970 mm TL 1 O GA Hyslop (2007) 1575 mm SVL m 11 Jun 2004 Eastern Ratsnake 1 N FL Layne and Steiner (1996) Eastern Ratsnake;1000 mm TL 1 O FL S. Godley 1400 mm TL m 6 Jun 1976 Swallowed prey headfirst; hydric hammock habitat Red Cornsnake (Pantherophis 1 O FL R. Bolt 1630 mm TL m Jul guttatus (L.)) Red Cornsnake 1 R FL R. Bolt 2010 mm TL m Jun Red Cornsnake 1 O FL Steiner et al. (1983) ca. 1840 mm TL 11 Mar 1954 Red Cornsnake; adult 1 O GA Stevenson et al. (2003) Adult 12 Nov 1989 Red Cornsnake; adult, 914 mm TL 1 R GA D. Stevenson 2229 mm TL; m 26 Apr 2005 1880 mm SVL Red Cornsnake; hatchling, 255 mm TL 1 N GA D. Stevenson 1637 mm TL m 10 Oct 1993 Also contained mammal hair; GSU #93.12646 Red Cornsnake; dead (DOR) 1 O FL Steiner et al. (1983) Red Cornsnake; 1220 mm TL 1 O FL J. Watt 1524–1829 mm TL Feb 2009 Red Cornsnake; 1067 mm TL 1 O FL J. Watt Adult ca. 1990 Red Cornsnake; ca. 508 mm TL 1 O FL B. McGighan 610 mm TL autumn Young-of-the-year indigo Rough Green-snake (Opheodrys 1 N FL Steiner et al. (1983) aestivus (L.)) Serpentes: Viperidae Southern Copperhead (Agkistrodon 1 N GA Stevenson et al. (2003) 1426 mm SVL m 10 Oct 2001 Also contained Southern contortrix (L.)), 610 mm TL Toad Cottonmouth (Agkistrodon piscivorus 1 O FL Smith and Voigt (2005) Adult 1 Nov 2005 (Lacepede)) Cottonmouth 1 R GA Landers and Speake (1980) Adult Pygmy Rattlesnake (Sistrurus miliarius 2 N FL Babis (1949) 1828 mm SVL 7 Nov 1948 Also contained 4 turtle (L.)); 305 mm TL, 356 mm TL eggs Pygmy Rattlesnake 1 R GA Mount (1975) 2130 mm TL Also toad, hatchling Gopher Tortoise, and Southern Hog-nosed 16 Southeastern Naturalist Vol. 9, No. 1 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Pygmy Rattlesnake 4 O FL Smith (1987) 2 juveniles Aug/Sept 1985 and 1986 Pygmy Rattlesnake 3 F FL Smith (1987) Juveniles 1986 Pygmy Rattlesnake 1 O FL C. Webb ca. 1372 mm TL Eastern Diamond-backed Rattlesnake 1 O GA M. Smith Adult (Crotalus adamanteus (Palisot de Beauvois)) Eastern Diamond-backed Rattlesnake 1 O FL H. Kale Adult Eastern Diamond-backed Rattlesnake 3 R GA Landers and Speake (1980) Adults Eastern Diamond-backed Rattlesnake 1 N GA Stevenson et al. (2003) 1514 mm SVL f 17 Oct 1997 Also contained hatchling Gopher Tortoise; GSU #97.0494 Eastern Diamond-backed Rattlesnake 1 O GA Stevenson et al. (2003) Adult Eastern Diamond-backed Rattlesnake; 1 O FL Layne and Steiner (1996) Adult ca. 914 mm TL Eastern Diamond-backed Rattlesnake 1 O FL K. Dyer Adult Eastern Diamond-backed Rattlesnake; 1 O FL Dodd and Barichivich (2007) 1105 mm SVL m 17 July 1986 Also mentioned in 600-700 mm TL Timmerman (1995) Eastern Diamond-backed Rattlesnake; 1 O FL C. Schmittler 1372 mm TL ca. 610 mm TL Timber Rattlesnake (Crotalus 1 O GA Hyslop (2007) 1575 mm SVL m 13 Jun 2003 horridus (L.)) Timber Rattlesnake 1 O GA Hyslop (2007) 1780 mm SVL m 17 Jul 2003 Timber Rattlesnake 1 O GA Hyslop (2007) 2030 mm TL; m 12 Jul 2004 1690 mm SVL Serpentes: Elapidae Harlequin Coral Snake (Micrurus 1 O FL Layne and Steiner (1996) fulvius (L.)) Harlequin Coral Snake; ca. 750 mm TL 1 O FL Belson (2000) ca. 1250 mm TL 7 Oct 1998 Serpentes: Unidentified “Ringed” snake (cf. Micrurus fulvius) 1 O FL Steiner et al. (1983) Snake scales 1 F FL R. Bolt 1880 mm TL f Jan 2010 D.J. Stevenson et al. 17 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Aves Galliformes: Phasianidae Domestic Chicken (Gallus domesticus); 8 R FL A. Flanagan Adult eggs Domestic Chicken; chick 1 O FL Layne and Steiner (1996) Adult Passeriformes: Corvidae Florida Scrub-jay (Aphelocoma 1 O FL Mumme (1987) 1427 mm TL f 30 Aug 1986 ca. 4-month-old bird coerulescens (Bosc)); juvenile being swallowed on the ground Passeriformes: Icteridae Eastern Meadowlark (Sturnella 1 N FL Layne and Steiner (1996) Adult magna (L.)) Passeriformes: Emberizidae Eastern Towhee (Pipilo 3 O FL R. Ashton Adult m Ambushed 1 Eastern erythrophthalmus (L.)); adults Towhee on 3 separate occasions as they bathed in artificial tortoise pond Unidentified bird 1 N FL Layne and Steiner (1996) Adult Mammalia Didelphimorphia: Didelphidae Virginia Opossum (Didelphis 1 O FL Smith and Voigt (2005) 1630 mm SVL, m 29 May 2004 virginiana (Kerr)); juvenile 1589 grams Lagamorpha: Leporidae Marsh Rabbit (Sylvilagus palustris 1 O FL Alvarez (1996) 2130 mm TL 29 Feb 1996 “very young marsh (Bachman)); nestling rabbit” Eastern Cottontail (Sylvilagus 3 F1, O2 FL Layne and Steiner (1996) 3 different adults Two observed were fl oridanus (J.A. Allen)) recent nestlings Rodentia: Cricetidae Cotton Mouse (Peromyscus 1 F FL Smith (1987) Juvenile 1986 gossypinus (LeConte)) 18 Southeastern Naturalist Vol. 9, No. 1 Prey items # So State Observer/ citation Size Sex Date Notes on Prey Eastern Harvest Mouse 1 R GA Landers and Speake (1980) Adult (Reithrodontomys humulis (Audubon and Bachman)) Hispid Cotton Rat (Sigmodon hispidus 1 N FL Steiner et al. (1983) Adult Say and Ord) Hispid Cotton Rat 7 N2, F5 FL Layne and Steiner (1996) Several different adults Prey items included 1 recently born young, 3 small juveniles, 1 subadult, 1 adult Hispid Cotton Rat; subadult 1 N GA Stevenson et al. (2003) 1156 mm SVL f 14 Dec 2001 Hispid Cotton Rat; adult 1 O FL A. Nielson Adult April/ May 1991 Hispid Cotton Rat 1 R FL S. Godley Adult f 30 June 1974 Old field habitat Rodentia: Muridae House Mouse (Mus musculus (L.)) 1 R GA Landers and Speake (1980) Adult Black Rat (Rattus rattus (L.)) 2 N, F FL Layne and Steiner (1996) 2 different adults Rodentia: Sciuridae Southern Flying Squirrel (Glaucomys 2 R, F FL Layne and Steiner (1996) 2 different adults volans (L.)) Rodentia: Unidentified Unidentified small rodent 1 N FL Layne and Steiner (1996) Mammals: Unidentified Mammal hair 1 N GA D. Stevenson 1637 mm TL m 10 Oct 1993 Also contained hatchling corn snake; GSU #93.12646 Mammal hair in feces 1 F FL R. Bolt 1690 mm TL m Jan Mammal hair in feces 1 F FL R. Bolt 1980 mm TL m Jan