Illawarra mammals

Mammals are a group of animals that have a skin covered with hair, are warm-blooded and suckle their young. This includes monotremes (Platypus and Echidna), marsupials (wallabies, possums, gliders and Antechinus) and placentals (Bush Rats, bats). For the purpose of this review I exclude marine mammals such as whales and dolphins as it is unlikely that these will occur in your garden, even with rising sea levels! The table below lists the 48 species of mammal in the region, half of which are bats. Most of these are forest-dependent, that is, they require large areas of bush and trees that support hollows for den sites. Forest-dependent species are unlikely to occur in an urban setting but if you have a rural property along the escarpment then the chances of these species being present is enhanced.

Echidnas occasionally visit urban gardens adjacent to bushland, as well as turning up on rural properties. Image by Emma Rooksby.

Native mammals of the Illawarra (excluding Bomaderry Creek bushland)

Note species marked with * are listed as threatened under the NSW Biodiversity Conservation Act (2016)

Family	Species	Common name
Tachyglossidae	Tachyglossus aculeatus	Echidna
Ornithorhynchidae	Ornithorhynchus anatinus	Platypus
Dasyuridae	Antechinus stuartii	Brown Antechinus
	Antechinus swainsonii	Dusky Antechinus
	Dasyurus maculata	Spotted-tailed Quoll*
	Sminthopsis murina	Common Dunnart
Peramelidae	Perameles nasuta	Long-nosed Bandicoot
Phascolarctidae	Phascolarctos cinereus	Koala*
Vombatidae	Vombatus ursinus	Common Wombat
Phalangeridae	Trichosurus caninus	Mountain Brushtail Possum
Phalangeridae	Trichosurus vulpecula	Common Brushtail Possum
Burramyidae	Cercartetus nanus	Eastern Pygmy Possum*
Petauridae	Petaurus breviceps	Sugar Glider
Pseudocheiridae	Petauroides volans	Greater Glider
	Pseudocheirus peregrinus	Common Ringtail Possum
Tarsipedidae	Acrobates pygmaeus	Feathertail Glider
Potoroidae	Potorous tridactylus	Long-nosed Potoroo*
Macropodidae	Macropus giganteus	Eastern Grey Kangaroo
	Macropus robustus	Wallaroo
	Macropus rufogriseus	Red-necked Wallaby
	Wallabia bicolor	Swamp Wallaby
Pteropodidae	Pteropus poliocephalus	Grey-headed Flying Fox*
	Pteropus alecto	Black Flying Fox
	Pteropus scapulatus	Little Red Flying Fox
Emballonuridae	Saccolaimus flavientris	Yellow-bellied Sheathtail-bat*
Molossidae	Mormopterus norfolkensis	Eastern-coast Free-tail Bat*
	Mormopterus planiceps	Eastern Free-tail Bat
	Austronomus australis	White-striped Free-tail-bat
Rhinolophidae	Rhinolophus megaphyllus	Eastern Horseshoe-bat
Vespertilionidae	Chalinolobus dwyeri	Large Pied Bat*
	Chalinolobus gouldii	Gould's Wattle Bat
	Chalinolobus morio	Chocolate Wattle Bat
	Falsistrellus tasmaniensis	Eastern False Pipistrelle*
	Kerivoula papuensis	Golden-tipped Bat*
	Miniopterus australis	Little Bent-wing Bat*
	Miniopterus schreibersii	Eastern Bent-wing Bat*
	Myotis macropus	Southern Myotis
	Nyctophilus geoffroyi	Lesser Long-eared Bat
	Nyctophilus gouldi	Gould's Long-eared Bat
	Scoteanax ruppellii	Greater Broad-nosed Bat*
	Scotorepens orion	Eastern Broad-nosed Bat
	Vespadelus darlingtoni	Large Forest Bat
	Vespadelus pumilis	Eastern Cave Bat
	Vespadelus regulus	King River Bat
	Vespadelus vulturnus	Little Forest Bat
Muridae	Hydromys chrysogaster	Water-rat
	Rattus fuscipes	Bush Rat
	Rattus lutreolus	Swamp Rat

Urban native mammals

Some native mammals are robust to change and have adapted to urban life. These include the Common Brushtail Possum and Common Ringtail Possum. What are the characteristics of these species that have allowed them to persist in suburbia? For a start neither species has to den in tree hollows. A Brushtail Possum is quite happy living in your ceiling and a Ringtail Possum can make its own nest (called a dray) by gathering sticks to make a ball shaped nest in a thicket. Both species are capable of having lots of babies over their life so they can withstand a degree of mortality from road kill and dogs/cats/fox.

Common Brushtail Possum, one of the most regularly sighted local mammals. Image by Garry Daly ©.

Apart from the Common Brushtail Possum and Common Ringtail Possum the other native mammal frequently seen in urban landscapes is the Grey-headed Flying Fox as it can fly to access food trees. In the northern suburbs of Wollongong the Long-nosed Bandicoot also persists but mostly in patches of bush close to the coast. On occasion an Echidna may wander into yards of blocks that border the escarpment. Certain species of microbat may den in houses, with several cases of Eastern Freetail Bat, Southern Freetail Bat and Gould's Wattled Bat living in buildings. The Large Bent-wing Bat and Gould's Wattled Bat can roost in man-made structures such as disused railway tunnels, stormwater drains. The Little Forest Bat is sometimes found roosting in the folds of outdoor umbrellas or under hanging coats.

Rural native mammals

In a rural landscape people are more likely to see a range of native mammals compared to those living in urban areas. The Swamp Wallaby has a reputation for eating and breaking native plants grown in revegetation work, while many people have to deal with Brown Antechinus invading their houses in winter to form leks. A lek occurs when a bunch of male Antechinus find a cosy spot such as a clothes drawer to perform in front of females hoping to score a partner. The resulting mess from faeces is not a good look.

The dark colouring and heavy-set body of Swamp Wallaby make the species fairly easy to recognise. Image by Garry Daly ©.

Most Australian mammals are nocturnal so are best seen at night with the aid of spotlights. Some are rare and have large home ranges so are rarely seen. Several years after we moved to a rural setting Spotted-tailed Quoll made their presence felt only after we got poultry. After the chickens and geese were given away the offending animal took up residence in our ceiling, raided the garbage tin for left over cream cheese and even came into the house a few times! Quolls are rare, often being hit by cars and shot by uninformed people. I have been told that historically quolls used to come around dairies to lick spilt milk.

(The table above lists the Common Dunnart (Sminthopsis murina) as occurring in the region. The threatened White-footed Dunnart (Sminthopsis leucopus) is very similar-looking to the Common Dunnart, and to date an animal trapped at Budgong is the most northerly record vouchered specimen (M.32088) within a museum (Murphy 2017). If you look at the Atlas of Living Australia records for the White-footed Dunnart you will see there is an error in the locality of the Murphy specimen, as it is placed further north in Kangaroo Valley. You can also see that there is an old record made by Eric Worrell. Worrell's record is placed at Gosford; that historic location of the Reptile Park, but the origin of the specimen has been obscured by time. There are a number of records of the Common Dunnart in the Illawarra region.)

Like the Quoll the Koala has also become rare in the region. There may still be a small population in Seven Mile Beach National Park and the adjacent area as a few people have seen individuals, and their preferred feed tree the Swamp Mahogany (Eucalyptus robusta) exists around Coomonderry Swamp. There is also a small population around Albion Park where they are associated with Forest Red Gum (E. tereticornis). Elsewhere Koala appear to be making a comeback with detections along the escarpment west of Wollongong in 2017.

The iconic Koala has been spotted in the Illawarra in recent times. Image by Garry Daly ©.

The Wombat has made a comeback since early European settlement with large populations existing along the escarpment from Cambewarra north to Saddleback. Wombat are common in many rural areas and can cause damage to fences, buildings and plants used for revegetation. If you live in a rural landscape you can manage native animals (and feral deer) by making wire cages to protect plants used in revegetation and building secure quoll-proof cages for poultry.

Wombats are generally most active at night. Image by Garry Daly ©.

There are several gliders in the region, the most common being the Sugar Glider. This small marsupial makes a soft barking call at night and makes tell-tale incisions on some plants such as Red Bloodwood (Corymbia gummifera). They persist in urban areas that have hollow-bearing forest and wattles. Sugar Gliders incise wattles to eat the sugary sap. Surprisingly they are a common pet in north America and have become feral in that part of the world. The Illawarra (as defined here) does not have Yellow-bellied Gliders but there is an isolated population in Bomaderry Bushland. The species is highly associated with Grey Gum (E. Punctata) that they incise to procure sap.

The Sugar Gilder's body is 16-21cm long, and its tail is a similar length. Image by Garry Daly ©.

The Feathertail Glider is tiny - its body is 6-8cm long and its feathery tail is a similar length. Image by Garry Daly ©.

The Illawarra does have Greater Gliders with a large isolated population existing at Seven Mile Beach National Park where they are associated with the old growth Blackbutt (Eucalyptus pilularis) forest as they eat the leaves of this species. I have monitored this population and it is robust but fragmented as a result of clearing, evidence that was advanced to secure the population being listed as an endangered population under the NSW Biodiversity Conservation Act (2016). Elsewhere in the Illawarra this species is rare or absent as a result of the clearing of the escarpment forest for pit props during the early workings of coal mines. As the Blackbutt forests along the escarpment mature and form hollows large enough for this animal to use as dens they will hopefully recolonise these forests.

There are four species of macropod (Wallabies and Kangaroos) in the region. Unfortunately we have lost the Parma Wallaby and Red-necked Pademelon as a result of clearing and predation by Fox. The Swamp Wallaby is common and different to the other species of macropod as it browses on the growing tips of plants. This habit is really annoying to bush regenerators as they can destroy young plants. The other species have a grazing habit and are less likely to cause damage to young trees and shrubs. The Eastern Grey Kangaroo does not appear to have occurred naturally along the coastal plain north of the Shoalhaven River. The populations north of the river are a result of deliberate introductions to Bundanon, upper Kangaroo Valley and Foxground. They now occur as far north as Dunmore.

Eastern Grey Kangaroo. Image by Garry Daly ©.

Red-necked Wallaby with pouched young. Image by Garry Daly ©.

There are three species of Flying Fox in the Illawarra. The most common is the Grey-headed but on occasion the Little Red Flying Fox is seen. More recently the larger Black Flying Fox has turned up. This species has made a remarkable change in its distribution over the last 30 years. Historically it was only found north of Brisbane but by 1998 was firmly established in northern NSW and now has a large population in Sydney with a few animals being found in the Illawarra. Clearing of habitat probably prompted the Black Flying Fox to move south but in doing so it now competes with the Grey-headed for food. Flying foxes are important as they disperse seeds of rainforest trees (in particular figs) and pollinate trees, especially eucalypts. The biggest threats to all Flying Foxes is clearing of forest and extreme summer heatwaves as a result of climate change.

Grey-headed Flying Fox, one of the region's most important pollinators. Image by Garry Daly ©.

The Little Red Flying Fox is less common in the region.Image by Garry Daly ©.

There are 16 species of microbat in the Illawarra. Most live the hollows of trees but some such as the Bent-wing bats, Eastern Horseshoe Bat and Large-eared Pied Bat live in caves. All microbats eat insects and are important in keeping a balance in the moth and spider populations. Like the Black Flying Fox there has been one and maybe two species that have colonised the region in recent times, probably as a result of the minimum temperatures rising as part of global warming. The Little Bent-wing Bat only turned up in the region about 10 years ago while the Eastern Cave Vespadelus was only found in 1998 in the Saddleback-Foxground area. A few species are spring-summer migrants. They include the very rare Yellow-bellied Sheathtail-bat, White-striped Freetail-bat and possibly the Golden-tipped Bat.

Microbats roost in a variety of places. The Eastern Bent-wing Bat roosts in caves during winter at Bungonia and then disperse during spring. Other cave-roosting species include the Eastern Horseshoe-bat, Little Wattled Bat and Little Bent-wing Bat but other species may also roost in caves on occasion. Most of the other species roost in the hollows/cracks of dead and live trees. The Golden-tipped Bat is quite specific, roosting in rainforest beside creeks in the nests of the Yellow-throated Scrubwren and Brown Gerygone.

Some species of microbat such as the Golden-tipped Bat and Long-eared Bats forage mostly under the canopy whereas species such as the Yellow-bellied Sheathtail-bat and White-striped Freetail-bat mostly forage above the canopy. Some species such as the False Pipistrelle and King River Bat prefer forest at higher altitude whereas species such as the Eastern Broad-nosed Bat occur on the coastal plain (in our region). The most common microbat in the region is the Little Forest Bat. Microbats are a fascinating group to study because not much is known about them and they have complex life histories. They use sonar to locate food (flying insects) and communicate with each other. In many ways they are like birds as they fly and use calls to communicate. Most people cannot hear these calls except for the White-striped Mastiff Bat that has a high pitched series of clicks above 10 kHz.

The Golden-tipped bat is a habitat specialist, foraging for insects under the canopy along rainforest-edged creeks and roosting in the nests of Yellow-Throated Scrubwrens. Image by Garry Daly ©

The Illawarra has three species of rat. The Water Rat is rare being found around Coomonderry Swamp. The Bush Rat is common to abundant whereas the Swamp Rat is relatively less common. There appears to be more Swamp Rats in Wollongong and further north than in the south of the Illawarra. I was surprised to catch quite a few Swamp Rat when we cleared the drainage lines around Port Kembla north rail station of Cumbungi (Typha sp.). The rats that I normally associate with dense heath were living in a highly modified environment in Cumbungi.

The Swamp Rat is one of three local species of rat. It is distinguished by its short black tail and black feet.Image by Garry Daly ©

So what can you do to encourage native mammals to your garden? Plant shrubs and trees that provide food resources. In particular the nectar of flowering Coastal Banksia and Old Man Banksia are avidly sought by Flying Fox. Dense shrubs and trees such as Tea Tree (Leptospermum spp.) and Magenta Cherry (Syzygium paniculatum) provide places where Common Ringtail Possum may construct drays. If you want to provide artificial nesting boxes then these can be mounted on trees some 5m above the ground. Men’s sheds are places where the community can work together to build nest boxes and bat boxes for local residents and/or schools, and instructions are available for building boxes that suit different species. High schools should be encouraged to build nest boxes as part of wood technology. If space permits then winter-flowering trees such as Forest Red Gum and Swamp Mahogany may be planted. Sugar Gliders forage on the flowers of these trees.

Useful plants to attract mammals

Common name	Scientific name	Fauna attracted	Use
Two-veined Hickory	Acacia binervata	Sugar Glider	Sap/insects
Green Wattle	Acacia irrorata	Sugar Glider	Sap/insects
Maidens Acacia	Acacia maidenii	Sugar Glider	Sap/insects
Black Wattles	Acacia mearnsii	Sugar Glider	Sap/insects
Blackwood	Acacia melanoxylon	Sugar Glider	Sap/insects
Heath Banksia	Banksia ericifolia	Antechinus, Eastern Pygmy Possum	Nectar and nesting sites
Coastal Banksia	Banksia integrifolia	Sugar Glider, Grey-headed Flying Fox	Nectar
Old Man Banksia	Banksia serrata	Sugar Glider, Grey-headed Flying Fox	Nectar
Red Bloodwood	Corymbia gummifera	Sugar Glider	Sap
Spotted Gum	Corymbia maculata	Sugar Glider, Feathertail Glider	Nectar
Blackbutt	Eucalyptus pilularis	Sugar Glider, Greater Glider, Grey-headed Flying Fox, Common Brushtail Possum	Nectar and leaves
Swamp Mahogany	Eucalyptus robusta	Koala, Grey-headed Flying Fox, Common Brushtail Possum, Common Ringtail Possum	Leaves, Nectar
Forest Red Gum	Eucalyptus tereticornis	Koala, Grey-headed Flying Fox, Common Brushtail Possum	Leaves, Nectar
Morton Bay Fig	Ficus macrophylla	Grey-headed Flying Fox	Fruit
Small-leaved Fig	Ficus obliqua	Grey-headed Flying Fox	Fruit
Coastal Tee Tree	Leptospermum laevigatum	Common Ringtail Possum	Refuge site for drays
Basket Grass	Oplismenus aemulus	Wallabies and Kangaroos	Leaves
Weeping Grass	Microlaena stipoides	Wallabies and Kangaroos	Leaves
Burrawang	Macrozamia communis	Bush Rats	Outside casing of seed
Kangaroo Grass	Themeda australis	Wallabies and Kangaroos	Leaves