Herpetological Review Herpetological Review - Doczine

13 cm deep (e.g., Spea hammondii; Morey 2005).Juvenile survival and movement can be important factors inpopulation persistence (e.g., Red-legged Frogs in Biek et al. 2002;Conroy and Brook 2003). For example, dispersal in most amphibianspecies probably occurs as juveniles (e.g., Berven and Grudzen1990; Dole 1971). Survival and movement probably are quite differentin many anuran species, and PIT-based telemetry could beused to improve knowledge about the ecology of juvenile and smalladult amphibians. However, the applicability of PIT-tag telemetryto free-ranging individuals could be limited. The technique willprobably work best with animals that have small home range sizesand are not likely to use the subterranean habitat deeper than 13cm during the period of study. Searching the terrestrial habitat formoving individuals (e.g., dispersing juveniles) could be labor-intensiveand thus costly and only generate low recaptures of markedanimals (see Arntzen et al. 2004 for a detailed analysis of the useof PIT tags and associated costs of a capture-mark-recapture studies).For example, searching the 14.4-m 2 enclosures took 6 ± 4 (±SD) minutes with the 0.20 × 0.25 m head antenna across all foresttypes. In addition, dispersing or migrating animals can move relativelylong distances in a short period when environmental conditionsare conducive to movement (e.g., a warm, rainy night forpond-breeding amphibians in Maine, USA), which would necessitatemore frequent relocation in these conditions.We used a PIT-pack to non-invasively identify 40 pairs of PITtaggedR. sylvatica in amplexus (Table 1), and relocate and monitor25 of these pairs until the female oviposited. The number ofpairs we identified and monitored until the female oviposited eachnight was highly correlated with the number of new egg masses inthe pond the following morning (Pearson’s correlation r = 0.983,p < 0.0001). This result indicates that we identified most of thefrogs that successfully bred in the pond and the other 59 frogs wecaptured entering the pond did not successfully breed. In mostinstances where both male and female were identified, we wereable to position the antenna underwater below the pair to read thefemale’s tag. In seven instances, we were able to identify only themale because his PIT tag interfered with detection of the female’stag (Table 1, additional pairs observed column). We lost track ofone pair prior to observing oviposition. The male stopped amplexusby releasing the female (Table 1, pairs disturbed column)when we placed the antennae near seven pairs. This disturbancetypically occurred after we identified the male and moved the waterand vegetation while moving toward the pair with the antenna toidentify the female. We speculate that using a PIT-pack to identifybreeding pairs of R. sylvatica was much less invasive than wouldbe required using other techniques. Identifying animals markedwith visual implant elastomer or toe clipping usually requires handling,and externally attached radio-transmitters can interfere withswimming and amplexus in some frogs (e.g., Muths 2003).In summary, we successfully used PIT-tag telemetry to trackrecently metamorphosed and adult ranids in the terrestrial andaquatic environments, and this technique has potential for manymore applications in anurans and other small animals, such asmonitoring of animals in the shallow subterranean environment.Limitations for PIT tag and PIT-pack use are tag size and limiteddetection range. We successfully implanted 12-mm tags into ranids> 30 mm SVL. Currently available, 8-mm tags should be suitablefor frogs > ~ 20 mm SVL and ~ 0.7 g, but use with smaller animalsis not possible due to tag size. Also, additional work is neededto assess the long-term affects of tagging on animals of this size. APIT-pack can detect 100% of tags in the terrestrial environment toa depth of 13 cm and > 90% of tags to a depth of 20 cm.Acknowledgments.—We thank Dawn Bavaro, Rebecca Dionne, AliciaMiller, Valerie Moreau, and Brian Shaw for their help in the field and lab.Frogs were collected under Maine Department of Inland Fisheries andWildlife Permits 05–281 and 06–377, and experiments were conductedunder University of Maine IACUC permit A2006–03–03. This researchwas supported by the LEAP project (Land-use Effects on AmphibianPopulations, National Science Foundation Grant No. 0239915) and theUSGS Maine Cooperative Fish and Wildlife Research Unit. Mention oftrade names does not imply endorsement by the U.S. government. Wethank Aram Calhoun, Daniel Harrison, Cynthia Loftin, and Alan Whitefor improving the manuscript. This is Maine Agricultural and Forest ExperimentStation Paper 2989.LITERATURE CITEDARNTZEN J. W., I. B. J. GOUDIE, J. HALLEY, AND R. JEHLE. 2004. Costcomparison of marking techniques in long-term population studies: PITtagsversus pattern maps. Amphibia-Reptilia 25:305–315.BAILEY, L. L., T. R. SIMONS, AND K. H. POLLOCK. 2004. Spatial and temporalvariation in detection probability of plethodon salamanders usingthe robust capture-recapture design. J. Wildl. Manage. 68:14–24.BERVEN, K. A., AND T. A. GRUDZIEN. 1990. Dispersal in the wood frog(Rana sylvatica): implications for genetic population structure. Evolution44:2047–2056.BIEK, R., W. C. FUNK , B. A. MAXELL, AND L. S. MILLS. 2002. What ismissing in amphibian decline research: Insights from ecological sensitivityanalysis. Cons. Biol. 16:728–734.BLOMQUIST, S. M., AND J. C. TULL. 2002. Rana luteiventris (Columbiaspotted frog). Burrow use. Herpetol. Rev. 33:131.CAMPER, J. D., AND J. R. DIXON. 1988. Evaluation of a microchip markingsystem for amphibians and reptiles. Texas Parks and Wildlife DepartmentRes. Publ. 7100-159:1–22.CECALA, K. K., S. J. PRICE, AND M. E. DORCAS. 2007. A comparison of theeffectiveness of recommended doses of MS-222 (tricainemethanesulfonate) and Orajel® (benzocaine) for amphibian anesthesia.Herpetol. Rev. 38:63–66.CONROY, S. D. S., AND B. W. BROOK. 2003. Demographic sensitivity andpersistence of the threatened white- and orange-bellied frogs of WesternAustralia. Popul. Ecol. 45:105–114.CUCHEROUSSET, J., J. M. ROUSSEL, R. KEELER, R. A. CUNJAK, AND R. STUMP.2005. The use of two new portable 12 mm PIT tag detectors to tracksmall fish in shallow streams. N. Am. J. Fish. Manage. 25:270–274.DOLE, J. W. 1971. Dispersal of recently metamorphosed leopard frogs,Rana pipiens. Copeia 1971:221–228.DUELLMAN, W. E., AND L. TRUEB. 1986. Biology of Amphibians. McGraw-Hill Book Co., New York, New York. 670 pp.EGGERT, C. 2002. Use of fluorescent pigments and implantable transmittersto track a fossorial toad (Pelobates fuscus). Herpetol. J. 12:69–74.GIBBONS, J. W., AND K. M. ANDREWS. 2004. PIT tagging: simple technologyat its best. Bioscience 54:447–454.HEYER, W. R., M. A. DONNELLY, R. W. MCDIARMID, L. C. HAYEK, AND M. S.FOSTER (eds). 1994. Measuring and Monitoring Biological Diversity:Standard Methods for Amphibians. Smithsonian Institution Press,Washington, D.C. 364 pp.HILL, M. S., G. B. ZYDLEWSKI, J. D. ZYDLEWSKI, AND J. M. GASVODA. 2006.Development and evaluation of portable PIT tag detection units: PITpacks.Fish. Res. 77:102–109.HODGKISON, S., AND J. M. HERO. 2001. Daily behavior and microhabitatuse of the waterfall frog, Litoria nannotis in Tully Gorge, eastern Aus-178 Herpetological Review 39(2), 2008