'Peregrinus', means "foreign false hand" in Latin (Sydney Metropolitan Wildlife Services Inc. 2000).
Perception Channels: tactile ; chemical
During the 1950's common ringtail possum populations severely declined in numbers. Currently populations seem to have recovered.
Deforestation in Australia has resulted in a loss of habitat for common ringtail possums, because they are almost exclusively arboreal. In suburban areas they are vulnerable to being struck by cars, or hunted by cats and dogs (Sydney Metropolitan Wildlife Services Inc. 2000).
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Common ringtail possums do not adversely affect humans. Unlike brushtail possums, they are not considered pests in suburban areas and do not nest within homes or human structures (Sydney Metropolitan Wildlife Services Inc. 2000).
None known.
Common ringtail possums are nocturnal and primarily folivorous. They feed mainly on eucalyptus leaves, but may also eat flowers, buds, nectar, and fruit. Part of the common ringtail possum's caecum is able to detoxify the tannins and phenols that are present in eucalyptus leaves, making them capable of taking advantage of this food source. A low metabolic rate helps to compensate for the low energy intake of common ringtail possums due to their specialized diet. Feeding occurs both during the first half of the night and, again, before dawn. Common ringtail possums prefer eating the youngest foliage of the plants they consume. This effects reproductive patterns, as the young leave the pouch and are weaned during times when flower and fruit growth peaks (Barnett et al. 1984).
When they are found in urban Australian areas, common ringtail possums eat rose buds (Sydney Metropolitan Wildlife Service Inc. 2000).
Common ringtail possums are found along the eastern coastline of Australia, Tasmania, and the southwestern corner of western Australia (Marsupial Society of Victoria Inc. 2000).
Biogeographic Regions: australian (Native )
Common ringtail possums have an extensive distribution. They occur in temperate or tropical areas but are rarely found in drier areas. It is thought that this wide habitat range is due to their ability to feed on a number of different plant species. They can usually be found in dense brush forests, as they favor environments that are plentiful with eucalyptus. The dense brush is also optimal for the construction of dreys. Along with several other species, the common ringtail possum occupies a range of niches comparable to the niche's of lemurs, monkeys, squirrels, and bushbabies in similar forests on other continents (Barnett et al. 1984; Lee and Smith 1984).
Terrestrial Biomes: forest
Average lifespan
Status: wild: 5.0 years.
Average lifespan
Status: captivity: 8.0 years.
Average lifespan
Status: wild: 6.0 years.
Common ringtail possums are the smallest of eight species of ringtail possums that live in Australia. The adults of this species typically are between 30 and 35 cm in body length, with a tail length that is roughly equal to the body length. Common ringtail possums have brown or reddish fur on the upper surfaces of the body and light colored or gray fur on the ventral surfaces. Common ringtail possums have large eyes which are well adapted to seeing at night. Two of the claws found on the front feet are opposable and the pads, as well as the tips, of the toes are grooved. They possess a strong, but relatively hairless, prehensile tail. This tail is carried tightly curled when not in use. These animals can be distinguished from other possum species in several ways. Their ears are smaller and more rounded and they typically have patches of white fur both on and above the ears. The tail of common ringtail possums has a white tip and is tapered (Marsupial Society of Victoria Inc. 2000; Wildlife Welfare Org. of S.A. 2000).
Range mass: 500 to 1000 g.
Average mass: 700 g.
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 2.27 W.
Common ringtail possums are marsupials, thus they carry their young in a pouch while they develop. Mating takes place between April and December, depending on the location in Australia. Most young are born sometime between May and July. Both males and females are sexually mature in the mating season after their birth. Common ringtail possums are polyestrous as well as polyovular. The estrous cycle of this species lasts for 28 days (Barnett et al. 1984).
Most common ringtail possums have litters of two offspring, however they can have up to four. It has been suggested that six embryos are born at the same time, however, only two of those six are able to find a useable nipple, thus the other four usually die. The female's pouch has a forward facing opening; two of the four nipples are functional at one time. Older females can produce up to two litters of young per year (Wildlife Welfare Org of S.A. 2000).
Initial growth of the common ringtail possum young is generally slow. This slow growth occurs during the period when female weight is lowest. Between 90 and 106 days after birth, the young both open their eyes and are able to make clear vocalizations. Between 120 and 130 days after birth the young emerge from their mother's pouch. However, lactation generally does not stop until between 180 and 220 days after birth, sometimes ending as early as 145 days (Barnett et al. 1984; Gilmore and Stonehouse 1997).
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 0.3 g.
Average number of offspring: 2.
Average age at sexual or reproductive maturity (male)
Sex: male: 365 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 365 days.
The common ringtail possum (Pseudocheirus peregrinus, Greek for "false hand" and Latin for "pilgrim" or "alien") is an Australian marsupial.
It lives in a variety of habitats and eats a variety of leaves of both native and introduced plants, as well as flowers, fruits and sap. This possum also consumes a special type of faeces that is produced during the daytime when it is resting in a nest. This behaviour is called caecotrophy and is similar to that seen in rabbits.
The common ringtail possum is currently classified as the only living species in the genus Pseudocheirus; the species of Pseudochirulus and other ringtail genera were formerly also classified in Pseudocheirus. Several subspecies have been described, such as the Western Australian Pseudocheirus peregrinus occidentalis, but the entire population may be a species complex.[1] The arrangement as the only extant species of Pseudocheirus is:[1]
The common ringtail possum weighs between 550 and 1,100 g (19 and 39 oz) and is approximately 30–35 cm (12–14 in) cm long when grown (excluding the tail, which is roughly the same length again). It has grey or black fur with white patches behind the eyes and usually a cream-coloured belly. It has a long prehensile tail which normally displays a distinctive white tip over 25% of its length. The back feet are syndactyl, which helps it to climb. The ringtail possum's molars have sharp and pointed cusps.[4]
The common ringtail possum ranges on the east coast of Australia, as well as Tasmania and a part of southwestern Australia.[5] They generally live in temperate and tropical environments and are rare in drier environments. Ringtail possums prefer forests of dense brush, particularly eucalyptus forests.[5] The common ringtail possum and its relatives occupy a range of niches similar to those of lemurs, monkeys, squirrels, and bushbabies in similar forests on other continents.[6] It is less prolific and less widespread than the common brushtail possum.
The common ringtail possum is nocturnal and well adapted to arboreal life. It relies on its prehensile tail and sometimes will descend to the ground.[5] They communicate with soft, high-pitched, and twittering calls.[7]
The common ringtail possum feeds on a wide variety of plants in the family Myrtaceae including the foliage, flowers and fruits from shrubs and lower canopy.[8] Some populations are also known to feed on the leaves of cypress pine (Callitris), wattles (Acacia spp.) and plant gum or resins.[9][10]
When foraging, ringtail possums prefer young leaves over old ones. One study found the emergence of young possums from their pouches corresponds to the flowering and fruiting of the tea-tree, Leptospermum and the peak of fresh plant growth.[6] Young eucalypt leaves are richer in nitrogen and have less dense cell walls than older leaves; however, the protein gained from them is less available due to higher amounts of tannins.[11] When feeding, the possum's molars slice through the leaves, slitting them into pieces. The possum's caecum separates the fine particles from the coarse ones.[4] These particles stay in the caecum for up to 70 hours where the cell walls and tanned cytoplasts are partially digested.[12]
What distinguishes the digestive system of the common ringtail possum from that of the koala and the greater glider is the caecal content transfers directly back to the stomach. Because of this, the ringtail possum is able to gain more protein.[4] This is also done by lagomorphs like rabbits and pikas. Hard faeces are produced during the night while feeding and are not eaten, while soft faeces are produced during the day during rests and are eaten.[13]
The re-ingestion of caecal content also serves to maintain the ringtail possum's energy balance. Ringtail possums gain much of their gross energy from reingestion.[14] The common ringtail possum has a daily maintenance nitrogen requirement (MNR) of 290 mg N/kg0.75. Common ringtail possums gain much of their MNR from consuming their nitrogen-rich caecal pellets. They would have to gain 620 mg N/kg0.75 otherwise.[4] The ringtail possum recycles 96% of its liver's urea, which is then transferred into the caecum and made into bacterial protein. Only re-ingestion makes this effective and the bacterial protein must be digested in the stomach and the amino acids subsequently absorbed in the small intestine.[4] This recycling also allows the possum to conserve water and urinate less. Reingestion allows the possum to live on low nitrogen eucalyptus leaves which is particularly important during late lactation.[15] It has been found that at higher temperatures, the common ringtail possum consumes less food due to a limited ability to metabolize toxins found in their diet.[16] Because 55% of their water intake comes from the leaves and foliage they consume, their metabolic rate must remain low and stable while facing water loss.[17] In response to this challenge, common ringtail possums can control their body temperature and conserve water by using facultative hyperthermia to temporarily raise their internal body temperature, ranging from 29 to 39 °C (84 to 102 °F).[17]
Common ringtail possums live a gregarious lifestyle which centres on their communal nests, also called dreys.[18] Ringtail possums build nests from tree branches and occasionally use tree hollows. A communal nest is made up of an adult female and an adult male, their dependant offspring and immature offspring of the previous year.[8] A group of ringtail possums may build several dreys at different sites. Ringtail possums are territorial and will drive away any strange conspecifics from their nests. A group has a strong attachment to their site. In one experiment, in which a group was removed from their territory, it remained uncolonised for the following two years.[8] Ringtail possum nests tend to be more common in low scrub and less common in heavily timbered areas with little under-story.[4] Dreys contribute to the survival of the young when they are no longer carried on their mother's back.[4]
The common ringtail possum carries its young in a pouch, where it develops. Depending on the area, the mating season can take place anywhere between April and December.[5] The majority of the young are born between May and July. The oestrous cycle of ringtail possum lasts 28 days.[6] It is both polyoestrous and polyovular. If a female prematurely loses her litter, she can return to oestrous and produce a second litter in October as a replacement if conditions are right.[4] The average litter is two, although there are very occasionally triplets.[4] Common ringtail possum young tend to grow relatively slowly due to dilute milk with low lipid levels that is provided to the young. As with other marsupials, the common ringtail possum's milk changes through lactation.[19] During the second phase of lactation, more solid foods are eaten, especially when the young first emerges from the pouch.[19] During this time, the concentration of carbohydrates fall, while those of proteins and lipids reach their highest.[19] The long lactation of the ringtail possums may give the young more time to learn skills in the communal nest as well as to climb and forage in the trees.[4]
The young are first able to vocalise and open their eyes between 90 and 106 days of age.[5] They leave their mother's pouch at 120–130 days. However, lactation usually continues until 180–220 days after birth but sometimes ends by 145 days.[6] Both sexes become sexually mature in the first mating season after their birth.
Common ringtail possum populations severely declined during the 1950s. However, populations seem to have recovered in recent times.[5] Because they are largely arboreal, common ringtail possums are particularly affected by deforestation in Australia. They are also heavily predated upon by the introduced red fox. They are also hit by cars, or killed by snakes, cats and dogs in suburban areas.[5]
The common ringtail possum (Pseudocheirus peregrinus, Greek for "false hand" and Latin for "pilgrim" or "alien") is an Australian marsupial.
It lives in a variety of habitats and eats a variety of leaves of both native and introduced plants, as well as flowers, fruits and sap. This possum also consumes a special type of faeces that is produced during the daytime when it is resting in a nest. This behaviour is called caecotrophy and is similar to that seen in rabbits.
