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preocular are not fused. The specimens in our series have snoutventlength from 16.5 mm (hatchling) to 43.6 mm (largest adult).The eggs, collected from under leaf litter in the plots (see Table1), are creamy-white to yellow, oval, and leathery and average 8.2mm long by 4.8 mm wide (after preservation in 10% formalin).Most have a small, purplish-black spot visible through the eggshell.A fully developed skink is visible through the eggshell oftwo eggs (FMNH 258918). A baby skink hatched from one egg(FMNH 258917) immediately upon immersion of the egg in formalinin the field, making identification unambiguous. Animalswith regenerating tails accounted 5.5% of the specimens captured.The plot results for S. tridigitus are summarized in Table 1. Allindividuals and eggs from the census plots were found under leaflitter. Six of the eight plots (75%) contained this species and itwas clear that abundance was related to elevation. Intensive searchingover 16 days (10–25 September 1999) at these sites by theauthors and two camp assistants (and others sporadically) in theconventional way yielded only two individuals of this species, oneunder leaf litter when clearing a campsite and the other inside arotten log. Thus, by the standard methods of expeditionary fieldsurveys, this species would have been considered rare at the studysite. In fact, it was the most abundant reptile in the area. Withoutthe plot method the small numbers of individuals otherwise obtainedwould not have revealed this. No animals were found atlow elevations but they were relatively abundant at 1000 m. Populationdensity was lower again at 1200 m. Hence, this species ismost abundant at mid-elevations.At 1000 m on average there was one egg for every 3.5 adults,whereas at 1200 this value dropped to one egg for every 8.75 adultssuggesting either that reproductive rate was much lower at thehigher elevation, or that the reproductive season differed betweenthe two sites.This species, rather than being an insignificant rarity, is abundantat higher elevations on the Bolaven Plateau, where it accountedfor 86% of the total individuals of the forest-floor lizards and frogs(6 species; snakes inadequately sampled) at 1000 m and 57% ofthe individuals of forest-floor lizards and frogs (8 species) at 1200m. At a lower elevation on the plateau where S. tridigitatus wasnot present, it was replaced by a similarly small skink in theScincella reevesi complex (mean density: 0.05/m 2 ; 64% of totalindividuals of the forest-floor frogs and lizards; four species). Thesetwo skinks probably play an important role in the dynamics of theforest floor community as significant predators upon small invertebratesand as food for various snakes.Rodda et al. (2001a,b), using a censusing technique similar tothe present one, also found unexpectedly high densities of somesmall reptiles and it is likely that many small forest-floor lizardsare far more abundant than they appear to be. Estimates of densityare used in studies of population biology and structure of assemblagesand often play an important role in decisions about conservation.Much of the previous literature, even that based on fencedplots, probably contains serious underestimates and needs to bereassessed by research using more refined, fenced-plot techniques.Acknowledgments.—Fieldwork was conducted under the auspices ofthe Wildlife Conservation Society/Division of Forest Resource ConservationCooperative Program. Specimens were exported to the Field Museumof Natural History under permits issued by the Ministry of Agricultureand Forestry, Vientiane, Laos. This research was funded by the NationalGeographic Society, the Wildlife Conservation Society, the JohnD. and Catherine T. MacArthur Foundation and the North Carolina AgriculturalResearch Service.LITERATURE CITEDBAIN, R. H., T. Q. NGUYEN, AND K. V. DOAN. 2007. New herpetofaunalrecords from Vietnam. Herpetol. Rev. 38:107–117.BOURRET, R. 1939. Notes herpétologiques sur l’Indochine française. XVIII.Reptiles et batraciens reçus au Laboratoire des Sciences Naturelles del’Université au cours de l’année 1939. Descriptions de quatre espèceset d’une variété nouvelles. Annexe au Bulletin Général de l’InstructionPublique 4:5–39.GREER, A. E., P. DAVID, AND A. TEYNIÉ. 2006. The Southeast Asian scincidlizard Siaphos tridigitus Bourret, 1939 (Reptilia, Scincidae): a secondspecimen. Zoosystema 28:1–6.HEATWOLE, H. 2008. Quadrat sampling. In M. S. Foster (ed.), Methods forMeasuring and Monitoring Reptile Biodiversity. SmithsonianInstitution, Washington, DC. In press.––––––, AND O. J. SEXTON. 1966. Herpetofaunal comparisons betweentwo climatic zones in Panama. Amer. Midl. Nat. 75:45–60.RODDA, G. H., E. W. CAMPBELL III, AND T. H. FRITTS. 2001a. A high validitycensus technique for herpetofaunal assemblages. Herpetol. Rev.32:24–30.––––––, G. PERRY, R. J. RONDEAU, AND J. LAZELL. 2001b. The densest terrestrialvertebrate. J. Trop. Ecol. 17:331–338.TECHNIQUESHerpetological Review, 2008, 39(2), 170–174.© 2008 by Society for the Study of Amphibians and ReptilesBromeliad Patch Sampling Technique for CanopyHerpetofauna in Neotropical ForestsSHAWN F. MCCRACKEN*Department of Biology, Texas State University601 University Drive, San Marcos, Texas 78666, USATADPOLE Organization2214 South First, Austin, Texas 78704, USAandMICHAEL R. J. FORSTNERDepartment of Biology, Texas State University601 University Drive, San Marcos, Texas 78666, USA*Corresponding author; e-mail: smccracken@txstate.eduThe canopy strata of tropical forests are one of the remainingunexplored biotic frontiers. Canopy research is a relatively newdiscipline facilitated by recent methodological advances in canopyaccess techniques (Basset et al. 2003b). Forest canopies are amongthe most species-rich terrestrial habitats on earth, supporting approximately40% of known extant species and estimated to holdup to 50% of the earth’s biodiversity (Basset et al. 2003b; Mitchellet al. 2002). The ecological role of amphibians and reptiles in forestcanopies is mostly unknown. Thus far the research focus hasbeen on arthropods, birds, mammals, plants and ecological processes;investigations of canopy herpetofauna have only recentlybeen documented (De Vries et al. 1997; Guayasamin et al. 2006;170 Herpetological Review 39(2), 2008
FIG. 1. Schematic of tree with bromeliads illustrating distribution strategyfor sampling units (bromeliads), numbers denote bromeliads sampled.Schiesari et al. 2003). Kays and Allison (2001) reviewed publishedecology and study methods for arboreal tropical forest vertebratesand found amphibians and reptiles to be grossly understudied comparedto mammals, primarily due to their cryptic habits and samplingdifficulties. Of 752 articles on tropical forest arboreal vertebratespublished between 1988 and 1998 only 4% focused on reptilesand amphibians, with the majority of those covering reptiles(Kays and Allison 2001). While many studies report arboreal occupancyby an extensive number of amphibian species, few havedocumented ecological characteristics besides presence/absencedata based on calling males and new species descriptions(Duellman and Trueb 1986; Guayasamin et al. 2006; Schiesari etal. 2003). Most data for arboreal amphibians were obtained throughcollection and observation during reproduction of those speciesthat descend from the canopy to breed in water bodies at the forestfloor level (Duellman 1978; Duellman 2005; Ron and Pramuk1999). Standard survey techniques for amphibians, such as thoseat breeding sites, only encompass a small stratum (~2 m verticalheight) of forest diversity (McCracken et al. 2007). Amphibiansthat specialize within the upper canopy remain mostly unaccountedfor as a result of this limited vertical sampling bias (Guayasaminet al. 2006). More practical methods for studying canopy amphibiansand reptiles is a high priority to facilitate the need for moresurvey and natural history work (Kays and Allison 2001).A component of neotropical rainforest canopies that provide richfauna microhabitats are the phytotelmata, defined as plants or partsof plants which hold rainwater (e.g. bromeliads, fruits, inflorescences,palm fronds and tree holes). In some tropical locations theavailability of this habitat for aquatic organisms is up to 50,000liters per hectare, literally a “wetland in the sky” (Kitching 2000;McCracken and Forstner 2006). In particular, epiphytic tank bromeliadsare capable of holding relatively large amounts of waterand play a principal role as a “keystone resource” and microhabitatfor invertebrates, vertebrates and other plants (Nadkarni 1994).Canopy bromeliad arthropod surveys have reported them as reservoirsof incredibly high biodiversity (Basset et al. 2003a; Kitching2000). Typically, tank bromeliads occur in the upper canopy andoverstory trees of lowland rainforest at vertical heights between5–45 m. Bromeliads normally range in number of individuals from~5 to >150 on a single tree. Herein, we describe a technique forcanopy bromeliad patch sampling of herpetofauna in lowlandneotropical forests which is similar to those used in other canopyresearch disciplines but has not been documented for herpetofaunalinvestigations.Methods.—Bromeliad patch sampling was conducted during2004 and 2006 at the Tiputini Biodiversity Station (TBS)–Universidad San Franciso de Quito (USFQ), Orellana Province,Ecuador (00.63847°S, 076.14908°W, 217 m elev.). The vegetationtype of the site has been defined as Amazonian EvergreenLowland Forest (Palacios et al. 1999). Sampling units consistedof five bromeliads from each of 16 trees for a total of 80 bromeliadssampled. A tree was not sampled if less than 15 bromeliads ofany species to be sampled were present to ensure continued persistenceof the bromeliad community. Host trees were measuredfor diameter at 1.5 m above ground, height using a clinometer,and canopy cover using hemispherical photography with the GapLight Analyzer (GLA) software. A leader line was positioned inthe tree using a large slingshot (Sherrill Big Shot) which enablessetting lines at 30+ m. The canopy was accessed using singleropetechnique, which should only be performed by trained andexperienced individuals (Fig. 2d). The lowest and highest elevationbromeliads were sampled with the remaining three sampledat estimated even intervals in between (Fig. 1). Before removal ofeach bromeliad a wide-angle photograph was taken and the followingvariables collected: elevation, ambient air temperature,relative humidity, barometric pressure, water temperature and pHare measured inside one of the outer leaf bracts, and a 50 ml watersample is collected by siphon. Ambient air temperature, relativehumidity and barometric pressure were also collected at 1.5 melevation. The bromeliad was removed by holding several leavesat the tips in one hand and cutting its base support stem with apruning saw. The response of most animals is to retreat into thebromeliad bracts and therefore alleviates loss of specimens due toescape. The bromeliad was placed in a 55 gal. plastic bag withminimal disturbance, sealed, and placed in a tarp connected to arope that is threaded through a carabiner on the climbers harnessand the other end held by a ground support person. It was thengently lowered to the forest floor by the ground support person.Another photograph was taken of the site where the bromeliadwas removed. After removal of the five bromeliads, a herbariumsample was collected from the tree to confirm identification anddeposit in a herbarium. Bromeliads were processed at camp in ascreen tent to prevent escape of animals (Fig. 2c). Bromeliad waterwas strained through a 1 mm mesh screen to separate arthropods,leaf litter, and detritus. Water volume was measured with a graduatedcylinder. Bromeliads were measured, number of leavescounted, and photographed including a meter stick for scale reference(Fig. 2a, b). Individual leaves were removed to facilitate collectionof herpetofauna, which were temporarily stored in bagsHerpetological Review 39(2), 2008 171
Page 1 and 2: HerpetologicalReviewVolume 39, Numb
Page 3 and 4: About Our Cover: Zonosaurus maramai
Page 5 and 6: Prey-specific Predatory Behavior in
Page 7 and 8: acid water treatment than in the co
Page 10 and 11: TABLE 1. Time-line history of croco
Page 12 and 13: The Reptile House at the Bronx Zoo
Page 14 and 15: FIG. 6. A 3.9 m (12' 11 1 / 2") Ame
Page 16 and 17: One of the earliest studies of croc
Page 18 and 19: TABLE 2. Dimensions and water depth
Page 20 and 21: we call it, is in flux.Forty years
Page 22 and 23: Feb. 20-25. abstract.------. 1979.
Page 24 and 25: yond current practices (Clarke 1972
Page 26 and 27: poles (Pond 1 > 10,000, Pond 2 4,87
Page 28 and 29: ------, R. MATHEWS, AND R. KINGSING
Page 30 and 31: Herpetological Review, 2008, 39(2),
Page 32 and 33: TABLE 2. Summary of running (includ
Page 34 and 35: FIG. 2. Responses of adult Regal Ho
Page 36 and 37: PIANKA, E. R., AND W. S. PARKER. 19
Page 38 and 39: BUSTAMANTE, M. R. 2005. La cecilia
Page 40 and 41: Fig. 3. Mean clutch size (number of
Page 42 and 43: facilitated work in Thailand. I tha
Page 46 and 47: FIG. 2A) Side view photo of Aechmea
Page 48 and 49: 364.DUELLMAN, W. E. 1978. The biolo
Page 50 and 51: incision, and placed one drop of Ba
Page 52 and 53: 13 cm deep (e.g., Spea hammondii; M
Page 54 and 55: FIG. 1. Medicine dropper (60 ml) wi
Page 56 and 57: esearchers and Hellbenders, especia
Page 58 and 59: FIG. 3. Relative success of traps p
Page 60 and 61: data on Hellbender population struc
Page 62 and 63: aits sometimes resulted in differen
Page 64 and 65: trapping system seems to be a relat
Page 66 and 67: AMPHIBIAN CHYTRIDIOMYCOSISGEOGRAPHI
Page 68 and 69: TABLE 1. Prevalence of B. dendrobat
Page 70 and 71: Conservation Status of United State
Page 72 and 73: TABLE 1. Wood Frog (Rana sylvatica)
Page 74 and 75: TABLE 1. Anurans that tested positi
Page 76 and 77: is, on average, exposed to slightly
Page 78 and 79: (10%) were dead but not obviously m
Page 80 and 81: Submitted by CHRIS T. McALLISTER, D
Page 82 and 83: FIG. 1. Oscillogram, spectrogram, a
Page 84 and 85: FIG. 1. Adult Physalaemus cuvieri r
Page 86 and 87: Répteis, Instituto Nacional de Pes
Page 88 and 89: discovered 145 live hatchlings and
Page 90 and 91: GRAPTEMYS GIBBONSI (Pascagoula Map
Page 92 and 93: College, and the Joseph Moore Museu
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FIG. 1. Common Ground Lizard (Ameiv
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havior unavailable elsewhere. Here
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15% of predator mass, is typical fo
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side the third burrow and began a f
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We thank Arlington James and the st
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mm) S. viridicornis in its mouth in
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NECTURUS MACULOSUS (Common Mudpuppy
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LITHOBATES CATESBEIANUS (American B
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Research and Collections Center, 13
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BRONCHOCELA VIETNAMENSIS (Vietnam L
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Oficina Regional Guaymas, Guaymas,
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MICRURUS TENER (Texas Coralsnake).
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declining in this recently discover
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80.7372°W). 02 November 2005. Stev
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this effort, 7% of the 10 × 10 km
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the knowledge of the group. The aut
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which is listed under “Rhodin, A.
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noting that Sphenomorphus bignelli
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256 Herpetological Review 39(2), 20
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ISSN 0018-084XThe Official News-Jou
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