Double clutching Gould's monitors (Varanus gouldii) and Gray's monitors (Varanus oliveaceus) at the Dallas Zoo

  • Published source details Card W. (1994) Double clutching Gould's monitors (Varanus gouldii) and Gray's monitors (Varanus oliveaceus) at the Dallas Zoo. Herpetological Review, 25, 111.


This study is summarised as evidence for the following.

Action Category

Breed reptiles in captivity: Lizards

Action Link
Reptile Conservation
  1. Breed reptiles in captivity: Lizards

    A study in 1992–1993 at Dallas Zoo, USA (Card 1994) found that Gould’s monitors Varanus gouldii and Gray’s monitors Varanus olivaceus bred successfully in captivity. In 1992–1993, a female Gould’s monitor produced two clutches/year of 5–10 eggs/clutch. One clutch of five eggs was infertile and hatching success of the other clutches ranged from 50–100%. A female Gray’s monitor produced two clutches/year of 4–8 eggs/clutch, though only a single egg from the first clutch hatched successfully. Females were introduced to a male regularly for several days until courtship or copulation was observed.

    (Summarised by: William Morgan)

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