Breeding Phenology and Behavior of Rosenberg's Goanna (Varanus rosenbergi) on Kangaroo Island, South Australia

Abstract

For 16 years, we have observed and recorded seasonal life cycles of individual free-ranging Rosenberg's Goannas, Varanus rosenbergi. These monitor lizards are normally solitary except during their annual summer breeding cycle. Activities and behaviors were documented from precourtship through to pairing, courtship, copulation, selecting and excavating an incubation chamber, egg laying, and finally guarding the egg mound before returning to a solitary life style. Whereas the sequence of breeding activities tends to follow a set pattern, the timing and duration of physical and physiological events vary from season to season. Courtship through to defending the egg mound occupies up to 4 months of the year, commencing just before the summer solstice and ending shortly after the autumn equinox.