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Cannibalism in Varanus timorensis (Squamata: Varanidae) Reveals Some Reproductive Traits of Wild Population on Sabu Island, Indonesia

Evy Arida, Alexander Stubbs, Umilaela Arifin, Benjamin R. Karin, Sarah Hykin, Sean B. Reilly, Djoko T. Iskandar, Jimmy A. McGuire

Abstract


The Timor monitor lizard, Varanus timorensis, is unknown for its reproductive attributes in the natural habitats in the Lesser Sunda Islands, Indonesia. Timor monitors inhabit tropical forests and modified lands for agriculture with estimated breeding season between May and July. Reproductive characteristics and overall natural history of this species were observed more in captive populations than resulted from field observations. We report a part of the natural history of V. timorensis, which includes cannibalism of juveniles in wild populations on Sabu Island, Indonesia. Our current records of adult body sizes denote a range of mature females, some of which are likely to have reproduced. Body sizes of Timor monitors on Timor and Sabu suggest a seasonal mating of wild lizards that coincides with dry season and hatching of eggs during the wet season. Breeding for this species is likely to occur once every year. Nevertheless, currently there is no data available on female fecundity that may shed light into reproductive capacity and breeding strategy of Timor monitor across the distribution range in the Lesser Sunda Islands.

Keywords


body size; breeding; Lesser Sundas; prey; seasonal; Timor monitor

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References


Arida E., Mulyadi M., and Handayani N. W. (2020), «Captive reproduction of Timor monitor, Varanus timorensis (Gray, 1831) in Indonesia», IOP Conf. Ser. Earth Environ. Sci., 457(1), 012004.

Behrmann H. J. (1981), «Haltung und Nachzucht von Varanus t. timorensis (Reptilia: Sauria: Varanidae)», Salamandra, 17(3 – 4), 198 – 201.

De Buffrénil V. and Rimblot-Baly F. (1999), «Female reproductive output in exploited Nile monitor lizard (Varanus niloticus L.) populations in Sahelian Africa», Can. J. Zool., 77(10), 1530 – 1539.

Doody J. S., James H., Ellis R., Gibson N., Raven M., Mahony S., Hamilton D. G., Rhind D., Clulow S., and McHenry C. R. (2014), «Cryptic and complex nesting in the yellow-spotted monitor, Varanus panoptes», J. Herpetol., 48(3), 363 – 370.

Eidenmüller B. (1986), «Beobachtungen bei der Pflege und Nachzucht von Varanus (Odatria) t. timorensis (Gray, 1831) (Sauria: Varanidae)», Salamandra, 22(2 – 3), 157 – 161.

Fitch A. J., Goodman A. E., and Donnellan S. C. (2006), «A molecular phylogeny of the Australian monitor lizards (Squamata: Varanidae) inferred from mitochondrial DNA sequences», Australian J. Zool., 54(4), 253 – 269.

Frynta D., Frýdlová P., Hnízdo J., Šimková O., Cikánová V., and Velenský P. (2010), «Ontogeny of sexual size dimorphism in monitor lizards: males grow for a longer period, but not at a faster rate», Zool. Sci., 27(12), 917 – 923.

Géczy C. (2009), «Cannibalism in captive Varanus timorensis», Biawak, 3(2), 61 – 63.

Hamada J. I., Yamanaka M. D., Matsumoto J., Fukao S., Winarso P. A., and Sribimawati T. (2002), «Spatial and temporal variations of the rainy season over Indonesia and their link to ENSO», J. Meteorol. Soc. Jap. Ser. II, 80(2), 285 – 310.

Horn H. G. and Visser G. J. (1989), «Review of reproduction of monitor lizards Varanus spp. in captivity I», Int. Zoo Yearbook, 28(1), 140 – 150.

Horn H. G. and Visser G. J. (1997), «Review of reproduction of monitor lizards Varanus spp. in captivity II», Int. Zoo Yearbook, 35(1), 227 – 246.

King D. (1993), «Diet and reproductive condition of free ranging Varanus timorensis», West. Australia Nat., 19, 189 – 194.

King D. R. and Keirans J. E. (1997), «Ticks (Acari: Ixodidae) from varanid lizards in eastern Indonesia», Rec. West. Australia Mus., 18, 329 – 330.

King D. R. and Smith L. A. (2004), «Varanus timorensis», in: E. R. Pianka, D. R. King, and R. A. King (eds.), Varanoid Lizards of the World, Indiana Univ. Press, Bloomington and Indianapolis, pp. 275 – 278.

Lambertz K. (1995), «Haltung und zucht des Timorwarans (Varanus timorensis) mit verschiedenen zuchtgruppe», Monitor, 4(1), 30 – 38.

Marr A. B., Arcese P., Hochachka W. M., Reid, J. M., and Keller L. F. (2006), «Interactive effects of environmental stress and inbreeding on reproductive traits in a wild bird population», J. Anim. Ecol., 75(6), 1406 – 1415.

Mendyk R. W. (2012), «Reproduction of varanid lizards (Reptilia: Squamata: Varanidae) at the Bronx Zoo», Zoo Biol., 31(3), 374 – 389.

Moldovan D. (2008), «Husbandry and captive reproduction of Varanus (Odatria) similis, Mertens, 1958», Biawak, 2(2), 89 – 94.

Noble D. W., Keogh J. S., and Whiting M. J. (2013), «Multiple mating in a lizard increases fecundity but provides no evidence for genetic benefits», Behav. Ecol., 24(5), 1128 – 1137.

Roitberg E. S., Kuranova V. N., Bulakhova N. A., Orlova V. F., Eplanova G. V., Zinenko O. I., Shamgunova R. R., Hofmann S., and Yakovlev V. A. (2013), «Variation of reproductive traits and female body size in the most widely ranging terrestrial reptile: testing the effects of reproductive mode, lineage, and climate», Evol. Biol., 40(3), 420 – 438.

Schmutz E. and Horn H. G. (1986), «Der Lebensraum von Varanus (Odatria) timorensis (Gray, 1831) (Sauria: Varanidae)», Salamandra, 22(2/3), 147 – 156.

Sprackland R. G. (1999), «New species of monitor (Squamata: Varanidae) from Indonesia», Reptile Hobbyist, 4(6), 20 – 27.

Walls T. (2006), «Terrific Timors», Reptiles, 14(2), 30 – 33.




DOI: https://doi.org/10.30906/1026-2296-2023-30-2-118-123

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