Urban possums Thumping across the roof, living in the chimney or raiding our compost bins - possums are at home with people and in th...
Thumping across the roof, living in the chimney or raiding our compost bins - possums are at home with people and in the urban environment. With spring upon us, keep an eye out for joeys emerging from their mother's pouch and clinging to her back like furry backpacks.
The bushy-tailed Brushtails are agile climbers and are more often heard than seen, especially during the mating season. About the size of a small cat, they have silvery fur, large ears as well as the dark bushy tail.The most familiar and abundant of the many Australian possum species are the Brushtail possum (Trichosurus vulpecula) and the Common Ringtail possum (Pseudocheirus peregrinus)
Smaller than brushtails, Common Ringtails are easily identifiable by their white-tipped prehensile (gripping) tail, and two thumbs on each front foot, which helps them to grasp branches when climbing.
Both species have adapted well to living in the urban environment - a source of delight and frustration to many humans!
Brushtails breed predominantly in the autumn, although those in tropical or dry areas will breed throughout the year if food is abundant.
According to Belinda Alexandra, a possum coordinator for the Sydney-based Wildlife Information and Rescue Service (WIRES), female brushtails can breed at one year old, giving birth to a single baby 18 days after mating. The baby, like all marsupials, is blind and hairless and remains attached to a teat in the pouch where it develops rapidly over the next four to five months.
"The joey's first foray from the pouch is generally timed to coincide with warmer weather and the abundance of food provided by the onset of spring," she says. "It then spends another month or two coming and going from the pouch and riding on its mother's back until it is fully weaned and independent."
Ringtail possums are highly sociable and live in family groups that may contain a male, one or two females and juveniles from the previous year, which only reach maturity and leave home at 18 months old.
Carrying building materials curled up in their tails, males and females work together to construct large spherical nests, called drays, in hollow tree limbs, dense undergrowth or bunches of mistletoe. Lined with shredded bark or grass, there may be as many as five nests in the possums' home range. These frequently overlap with other possums' territories - including other females, with which the male might also have a relationship.
Although less noisy than the brushtail, the Common Ringtail is still very vocal and its soft, high-pitched twittering call is familiar to many suburbanites. Anatomically specialised as a leaf eater, it also eats flowers-rosebuds are a particular favourite-nectar, shoots and fruits, from both native and introduced garden plants.
Breeding seasons vary in different parts of Australia, and may occur from April to November. Two young are born and remain in the pouch for about four months until they are fully furred; both parents then carry them around on their backs until they are weaned at six months.
Urban expansion is putting pressure on native habitats, reducing the amount of natural environment for possums (and other animals) to live in. Many species of possums have proven capable of living in urban environments, although it's not always safe or easy.
Jacqui Brumm, Wildlife Curator at Brisbane's Lone Pine Sanctuary, says, that in addition to the Brushtail and Common Ringtail Possums found throughout the east coast, Brisbane residents are finding Mountain Brushtails are moving from their traditional hilly habitat into the outskirts and even some parts of the city centre.
"The reason for this gradual range expansion is probably a combination of pressures on traditional habitat caused by land clearing, and the rich pickings provided by the urban environment making it an attractive place to live," she says. "From a possum's perspective, our houses and other buildings are ideal - warm, dry and close to an almost limitless food source thanks to our gardens and compost bins.
Other possum species, like Gliders are found in many towns and cities, although these are rarely seen because they are shy, and require tall trees from which to glide. Smaller possums like the honey possum and feathertail gliders are confused with mice and are often trapped or poisoned.
Apart from natural hazards (which includes monitor lizards and powerful owls) possums are frequently injured or killed by cats, dogs and foxes, as well as power lines and cars; the latter accounts for an estimated 2.5 million native animals each year in NSW alone, mostly juvenile males moving to new territory, but often females with pouch young.
Belinda Alexandra says that despite their apparent numbers, we cannot afford to be complacent: urban possums in Sydney are fighting a losing battle for tree hollows, as more land is cleared and populations of feral bees and introduced Indian Minah birds drive them out. And even though they are protected species, some people regard possums as pests, and illegally trap or kill them.
Alexandra says WIRES advocates living harmoniously with wildlife, ensuring the needs of people and wildlife are met.
Keeping cats and dogs indoors after dark will help reduce the horrific injuries often suffered by possums. Planting a variety of natives like eucalypts, bottlebrushes, tea trees banksias, grevilleas, lili pillies, hakeas and wattles will ensure they have plenty of natural foods to eat. Using wildlife safe fertilisers and pest controls are also important, and it's also a good idea to cover chimneys with chicken wire to prevent possums falling in and becoming trapped.
If there are possums living in the roof and the arrangement is not working out, the most humane and practical way of removing these highly territorial animals is to provide alternate housing in the form of a nestbox placed near the roof. Shining a bright light in the ceiling for several days will help deter them from coming back and once you are sure the possum is not in the roof, block any gaps with chicken wire or timber.
Government bodies like the state parks and wildlife service, and native animal rescue organisations like WIRES may also be able to advise on removal strategies.
Special thanks to Belinda Alexandra and Jacqui Brumm.