Hi Swala Park, Broad marking on lips and tail (and ready use of tree) would be why John ('wombey') called this as a Tree Goanna (aka Lace Monitor, Varanus varius) rather than the other local species, Rosenberg's Goanna, which is reported more often on CNM. Timing is much earlier in the season than the nest digging by local Rosenberg's Goannas. Because of the leaves, I can't tell from the image if this goanna looks gravid. Did (she?) return to complete the hole, lay her eggs and partly backfill the hole? Was this a cannibal, excavating the young of another goanna? If there is further evidence, I'd be interested to hear - don.fletcher@emailme.com.au
Has not returned since I disturbed it. Did not appear to have eggs in the excavation and the white ants have since filled it in. Has been in the vicinity for the past couple of weeks as evidenced by upsetting the local magpies and cockatoos!
At nesting time gravid female Rosenberg's Goannas can dig several test holes in different mounds before the final one in which they lay. Final hole typically 0.5 -0.7 m deep down into the soft central 'carton' of the termite mound. Probably Tree Goannas are the same in this respect. Some females wait inconspicuously nearby for a few more weeks to guard the nest from cannibal goannas. If you see any of that I would love to hear don.fletcher@emailme.com.au