The Wolli Creek Valley has a surprisingly large array of fauna, particularly birds and reptiles. Bird records exist back to the 1940s, with 100 species being sighted each year in recent times. Previously unrecorded birds are added each year through monthly surveys by local volunteers.
Also recorded are seventeen species of native reptile, five frog, four mammal, and ten fish species, plus a variety of feral species.
This stretch of bushland is an attractive haven for birds. It provides food, shelter, and a resting place for migratory species and a niche in its own right for resident birds. It provides a major west-east corridor for migrants moving between the high country west of Sydney and the coast, and it serves as a significant stepping-stone across Sydney’s urban south for migrants moving north-south.
The valley’s many exposed sandstone outcrops, overhangs, crevices and ledges provide good habitat opportunities for reptile species, of which at least 17 species have been identified. Red-bellied Black Snakes are sometimes seen down near the creekline. A number of skink species, the Eastern Water Dragon and Long-Necked Turtle can also be found in the Valley.
Until recently, the Common Brushtail Possum (Trichosurus vulpecula), along with some microbat species, appeared to be the only surviving native mammals in the valley.
However, around mid-2007, a Grey-headed Flying-fox camp was established on the south side of Wolli creek in an area not readily accessible to the public. At first this camp involved only 50 or 60 Grey-headed Flying- foxes (Pteropus poliocephalus) but now at various times they are counted in the thousands.
Six native fish species have been identified in the freshwater section above the Henderson Street weir. In the brackish to salt water immediately below the weir, the following species have been collected: Sea Mullet, Yellow-fin Bream, Port Jackson Perchlet and Toadfish.
Following several decades of regrowth of native plant communities, there would now appear to be sufficient habitat to support viable populations of certain key native mammal species. But there is an apparent absence of the Bush Rat (Rattus fuscipes), Swamp Rat (Rattus lutreolus), Brown Antechinus (Antechinus stuartii), and Ringtail Possum (Pseudocheirus peregrinus). The Society would value discussion with, and research by experts in this area.
For more information see Fauna of the Wolli Valley in Inner south-west Sydney in The Natural History of Sydney (D. Lunney, P. Hutchings and D. Hochuli (eds), Royal Zoological Society of NSW, 2010).