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Herpetological Review Herpetological Review - Doczine

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havior unavailable elsewhere. Here we report three failed predationattempts by snakes on hatchling Cyclura cychlura cychlurafrom two island localities over an eight-day period in September2003.In coordination with a hatchling dispersal study of the AndrosIguana, we affixed 2.7 g radio-transmitters (model PD-2, HolohilSystems, Ltd., Ontario, Canada) to 41 hatchling iguanas (Knappand Owens 2005. Herpetol. Rev. 36:264–266) on Sandy and MangroveCays of Andros Island, Bahamas (see Knapp and Owens2004. Caribb. J. Sci 40:265–270 for site descriptions). We attemptedto locate telemetered hatchlings daily after release at theirrespective nests. On 3 September 2003 (20 days after release), wefound a dead hatchling C. c. cychlura (102 mm SVL, 45 g) on thelimestone substrate of Mangrove Cay. The head of this hatchlingwas severely compressed with blood seeping from the mouth andtympanum, while the head and thorax were coated with shiny clearand brown residue. The residue extended down half the body andstopped ca. 10 mm anterior to the transmitter, which was attachedon the dorsal side of the pelvic girdle. On 4 and 11 September2003 (3 days after release for each hatchling), we found deadhatchling iguanas (98 mm SVL, 43 g; 93 mm SVL, 38 g) on thelimestone substrate of Sandy Cay. The skull of each hatchling wassimilarly compressed with blood seeping from the mouth and tympanum.These hatchlings differed from the first observation in thatonly the head was coated with shiny clear and brown residue andstopped at the pectoral girdle. These observations are similar to afailed predation attempt on Sceloporus occidentalis (Sabo and Ku,op. cit.) and led us to conclude that the hatchlings had been captured,partially swallowed but regurgitated by a predator. Onlytwo snakes (Alsophis vudii and Epicrates striatus) occurring atour study sites have been confirmed to be capable of ingestinghatchling C. c. cychlura iguanas. Indeed, we recorded 18 A. vudiiindividuals consuming 19 C. c. cychlura hatchlings and six E.striatus individuals consuming nine hatchlings. We infer that thefailed predation attempts were attributable to A. vudii based onthe fresh, wet residue on the carcasses, which were discoveredduring the day. Additionally, based on observations of predatorpreyinteractions for both species of snakes using radio telemetry,the open locations of the carcass discoveries are indicative of typicalkill sites for the diurnal Alsophis rather than the nocturnal Epicrates.Snakes are known to feed selectively, and hence need to discriminatebetween objects that are or are not acceptable as food (Shineand Sun 2003, op. cit.). Our observations are significant becausethey indicate that potentially gape–limited snakes may be successfulin capturing and subjugating prey but can fail in their ingestionattempts. Sabo and Ku (op. cit.) concluded that a failed predationattempt of a gravid S. occidentalis was the direct result of the girthof the body cavity caused by the internal egg mass. In our case,the first failed predation event where the clear and brown residueextended to within 10 mm of the pelvic transmitter could be attributableto the increased girth caused by the transmitter. However,it appeared as if the ingestion process was aborted anteriorto the pectoral girdle in the latter two observations indicating thatthe snakes were able to dispatch but not ingest their prey items.We suspect that failed predation events may be more commonthan expected and that these events can provide interesting hypothesesfor testing evolutionary predator-prey relationships.We thank the Bahamas Department of Agriculture for permissionto conduct our research and permits. The John G. SheddAquarium and a grant from the Association of Zoos and Aquariums(AZA) Conservation Endowment Fund supported our research.Submitted by CHARLES R. KNAPP, Conservation and Researchfor Endangered Species, Zoological Society of San Diego,15600 San Pasqual Valley Road, Escondido, California 92027USA, and Conservation Department, John G. Shedd Aquarium,Chicago, Illinois 60605, USA (e-mail: cknapp@ufl.edu); andAUDREY K. OWENS, Arizona Game and Fish Department, 2221W. Greenway Rd., Phoenix, Arizona 85023, USA (e-mail:audreykowens@yahoo.com).ECPLEOPUS GAUDICHAUDII (NCN). REPRODUCTION.Ecpleopus gaudichaudii, a poorly known gymnophtalmid lizard,is thought to be endemic to the Atlantic Rainforest of southeasternBrazil (Peters et al. 1986. U.S. Nat. Mus. Bull. 297:1–293). Dataon clutch size and reproductive behavior is limited to one observationof two individuals (Uzzell 1969. Postilla 135:1–23). Herein,we report data on seven gravid females collected in Minas Gerais,southeastern Brazil.All specimens are deposited in the herpetological collection ofthe Universidade Federal de Minas Gerais (UFMG), BeloHorizonte, Brazil. All seven females, collected in arthropod and/or herpetofauna pitfall traps, contained one developed egg averaging7.0 ± 0.3 mm SD (range: 7.5–6.7 mm). UFMG 987 (36.6mm SVL) was collected in an area of secondary forest of a smallurban park, the Estação Ecológica da UFMG (19.92°S, 43.93°W;elev. 850 m) in the interval 24–30 October 2000. UFMG 1659,1663, 1661, and 1660 (respectively 34.9, 34.7, 35.2, and 35.3 mmSVL) were collected in primary forest of a large Atlantic Rainforestreserve, the Parque Estadual do Rio Doce (19.80°S, 42.63°W; elev.230–515 m) in the interval 1–10 September 2001. UFMG 1094(38.4 mm SVL) was collected in primary forest of another AtlanticRainforest reserve, the Reserva do Patrimônio Natural FelicianoMiguel Abdala (19.83°S, 41.83°W; elev. 340–680 m) in the interval22 December 2000–16 January 2001, whereas UFMG 1095(37.1 mm SVL) was collected in the same locality, but lacks acollection date. These observations agree with the previous observation(Uzzell 1969, op. cit.) that E. gaudichaudii clutch size istypically one egg.Submitted by FERNANDO A. PERINI, Laboratório deBiodiversidade Molecular, Departamento de Genética, Institutode Biologia, Universidade Federal do Rio de Janeiro, CP 68011,Rio de Janeiro, RJ, CEP 21941–590, Brazil (e-mail:faperini@yahoo.com.br); and MARIELLA BUTTI, Instituto deCiências Biológicas, Universidade Federal de Minas Gerais, CP486, Belo Horizonte, MG, CEP 31270–901, Brazil (e-mail:maributti@uol.com.br).ELGARIA COERULEA (Northern Alligator Lizard). JUVENILEGROWTH. Rutherford (2004. Can. J. Zool. 82:817-822) providedthe only juvenile growth data for Elgaria coerulea, but those datawere based on individuals from the Creston Valley, British Columbia,located toward the northern end of the species range222 <strong>Herpetological</strong> <strong>Review</strong> 39(2), 2008

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