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


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

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