By Toni Lynn Wainio
Geographic Range
Red-necked pademelons (Thylogale thetis) are only found in parts of eastern Australia. They range from eastern Queensland to just below mid-coast of New South Wales. (Nowak, 1995)
Biogeographic Regions:
australian 
(native ).
Habitat
The habitat of red-necked pademelons consists of rainforests, thick scrub or grassland areas, and eucalyptus forests. (Wahungu, Catterall, and Olsen, 2001)
These animals are found in the following types of habitat:
temperate ; terrestrial .
Terrestrial Biomes:
savanna or grassland ; rainforest .
Physical Description
(11.42 to 24.8 in)
Red-necked pademelons have a head and body length of 290 to 630 mm, with a tail length of 270 to 510 mm. They exibit sexual dimorphism in size, with the males weighing approximately 7 kg compared to the average female weight of 3.8 kg. (Hobart, William Smith Colleges, and Union College, 2002; Nowak, 1995)
Red-necked pademelons are grizzled gray in color above with a light hip stripe often present. The short tail of these animals is only lightly furred. It is also thick and rounded. (Nowak, 1995)
Some key physical features:
endothermic ; bilateral symmetry .
Sexual dimorphism: male larger.
Reproduction
These pademelons are apparently able to produce offspring once per year.
Breeding occurs during the autumn and spring in the north, and during summer in the south.
Little is known about mating systems in pademelons. Males in captivity tend to be somewhat aggressive toward one another. Taken with the pronounced sexual dimorphism in this species, this is suggestive of polygyny. Polygyny is common in macropods. (Nowak, 1995)
It has been recorded that female red-necked pademelons when in oestrus will be found around larger males, suggesting active mate choice by females. (Ord, Evans, and Cooper, 1999)
Mating systems:
polygynous .
Red-necked pademelons reach sexual maturity at about 18 months of age. Reproduction occurs in the autumn and spring in the north, and during the summer in the south. These pademelons usually give birth to a single young, although twins have been recorded in the genus. (Nowak, 1995)
Embryonic diapause is known to occur in red-necked pademelons. Embryonic diapause is when the division of the cells in the embryo stops when there are about 100 cells. This "started" but unfinished embryo is held in the uterus until conditions are right for development to continue. This allows for an embryo to be in the uterus while a mother is weaning another joey in the pouch. Once the nursing joey is weaned, development of the embryo can continue. The embryo experiences a short "actual" gestation period of approximately 30 days, but can stay in the pouch for up to 6 1/2 months. (Nowak, 1995)
In all marsupials, the young are altricial, and must make their way from the birth canal into a pouch, where they receive milk from the mother and complete their development. (Nowak, 1995)
In another member of the genus, T. billardierii, a joey stays in the pouch for 202 days, and weaning occurs about 4 months after the young permanently leave the pouch. Sexual maturity is slightly earlier in T. billardierii than in T. thetis, and it is possible that these other developmental events occur slightly later in the latter species as well. (Nowak, 1995)
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous ; embryonic diapause .
Parental care in this species has not been detailed in the literature. However, like other macropods, it is likely that the bulk of parental care is performed by the mother. Mothers nurse their joeys in a pouch, providing them with protection and grooming, until the young have developed enough to leave the pouch. Leaving the pouch permanently is a slow process, and during that time, the mother continues to nurse, groom, and protect her offspring. It is likey that T. thetis is like other macropods in this respect. (Nowak, 1995)
Parental investment:
no parental involvement; altricial ; pre-fertilization (protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female, protecting: female); pre-independence (provisioning: female).
Lifespan/Longevity
I found no documented information on this topic.
Behavior
Red-necked pademelons are solitary animals, sometimes forming small groups. They will sleep during most of the day in leaf litter and may bask in the sun when cold. (Nowak, 1995)
Red-necked pademelons rely on saltatorial locomotion for movement. They have an increased muscle fiber to tendon area ratio in their ankles. The tendons may be size or function dependent, and the strength of these tendons may limit locomotion. Thylogale thetis may also travel on all four legs and drag its tail behind, but, as in other macropods, this type of locomotion is reserved for slower travel. (Bennett, 2000; Nowak, 1995)
Home Range
Thylogale thetis has a home range of about 5 to 30 ha. (Hobart, William Smith Colleges, and Union College, 2002)
Key behaviors:
terricolous; saltatorial ; nocturnal ; motile ; sedentary ; solitary .
Communication and Perception
Red-necked pademelons communicate with one another using different clicks and by thumping their hind feet. As mammals, they also have visual capability, and probably use some visual signals, such as body postures, to communicate. Although not specifically reported for this species, it is likely that there are some scent cues, especially related to reproduction. Tactile communication occurs between mothers and their young, as well as between mates. (Nowak, 1995; University of Queensland, 2000)
Food Habits
Food consists of grass, leaves, roots and bark. Foraging behaviors of red-necked pademelons consist of feeding on forest edge at night. This apparently reduces their risk of falling prey to diurnal predators. A larger group size increases the range of feeding from forest cover. (Wahungu, Catterall, and Olsen, 2001)
Plant Foods:
leaves; roots and tubers; wood, bark, or stems.
Predation
- foxes (Vulpes)
- dingos (Canis lupus dingo)
- large birds of prey (Falconiformes)
Predators of red-necked pademelons are the introduced fox and the dingo, and possibly even large birds of prey. They decrease predation risk by foraging at night. (Hobart, William Smith Colleges, and Union College, 2002)
Ecosystem Roles
The major ecosystem role that red-necked pademelons play is that they are food for their predators. Through their foraging habits, they are likely to impact the growth of vegetation. (Hobart, William Smith Colleges, and Union College, 2002)
Economic Importance for Humans: Negative
There is no documented information about red-necked pademelons having a negative effect.
Economic Importance for Humans: Positive
Red-necked pademelons have been important for ecotourism in the areas in which they occur. (Hobart, William Smith Colleges, and Union College, 2002)
Ways that people benefit from these animals:
ecotourism .
Conservation Status
IUCN Red List: [link]:
Lower Risk - Least Concern.
US Federal List: [link]:
No special status.
CITES: [link]:
No special status.
The distribution of red-necked pademelons has decreased in Australia due to clearance of native vegetation for agriculture, dairying, and forestry. Even with this, the species is common in some areas. (Nowak, 1995)
The red-necked pademelon is not currently protected under CITES or IUCN.
Other Comments
Red-necked pademelon mothers may throw the joey out of their pouch during hard times to ensure that their own survival. This is a type of infanticide, but probably has a low cost to the mother because she is probably already pregnant with another offspring in embryonic diapause, just waiting for conditions to improve before proceding in its development. (Hobart, William Smith Colleges, and Union College, 2002)
For More Information
Find Thylogale thetis information at
Contributors
Nancy Shefferly (editor), Animal Diversity Web Staff.
Toni Lynn Wainio (author), University of Wisconsin-Stevens Point. Chris Yahnke (editor, instructor), University of Wisconsin Stevens Point.
