Have you ever seen goannas having sex? Christine Kaine hadn't - until last week when an amorous pair of reptiles got busy in her Merimbula back yard. "I was just sitting in my chair and saw them out the window," Christine told ACM. Christine said she wasn't sure what they were up to at first, "maybe fighting". But it quickly became apparent. "They did it a few times, I think the female was over it by the end. "She went up on to my roof and stayed there a few days. "I've seen plenty of goannas here, but never having sex!" According to the Australian Reptile Guide, during the September to December mating season, lace monitor males engage in "ritual combat" to establish dominance. Rival males rear up on their hind legs and grapple with each other, inflating their throats to intimidate each other. The "winner" will then approach the receptive female to mate. According to National Parks and Wildlife Service, around four to six weeks after mating, female lace monitors dig a hole in the ground, or in the side of a termite mound to lay between 6-12 eggs. The termites rebuild the mound over the eggs, keeping them safe and at a steady warmth. When the young hatch, around 8-9 months later, the female goanna returns to dig them out.