Recently classified as three separate species, long-beaked echidnas belong to an ancient clade of egg-laying mammals that includes the platypus of Australia. They are easily distinguished from short-beaked echidnas by their long snouts, which account for two-thirds of the length of the head. Despite laws designed to protect these species, they are in decline in areas accessible to humans. Echidnas have lost much of their forest habitat to logging, mining and farming, and are regarded as highly prized game animals by local people, who hunt them with specially trained dogs. One species, Attenborough's long-beaked echidna, is thought to have an extremely restricted range and may be at high risk of extinction.
Evolutionary Distinctiveness
Order: Monotremata
Family: Tachyglossidae
Long-beaked echidnas are monotremes, a group that also includes the short-beaked echidna and duck-billed platypus. Fossil evidence indicates that this group of mammals has changed very little during the last 100 million years. However, the fossils do not provide any evidence of the origins of the group and their ancestral relationships, nor to how they relate to marsupials and placental mammals. Fossil monotremes from the Pleistocene Epoch (which began 1.8 million years ago) are very similar to the living species.Echidnas are traditionally divided into two species, Tachyglossus aculeatus (short-beaked echidna) and Zaglossus bruijni (long-beaked echidna). However, there has been considerable controversy over this classification. Many scientists argue that the genus Zaglossus is actually composed of three species: Zaglossus bruijni (long-beaked echidna), Zaglossus attenboroughi (Attenborough's or Cyclops long-beaked echidna) and Zaglossus bartoni (Barton’s long-beaked echidna). According to this classification Z. bartoni is further divided into four subspecies.
Description
Size: Head and body length: 450-775 mm
Weight: 5-10 kg
The most distinguishing feature of long-beaked echidnas is their long snouts, which curve downwards and account for two-thirds of the length of the head. They have no teeth; instead their tongues are covered in spikes (teeth-like projections), which are very effective in hooking prey and drawing it into the mouth. They have compact, muscular bodies, with strong limbs and claws for digging. Their back and sides are covered with spines, which vary in colour from white through to dark grey or black. The body is also covered in brownish-black hairs, which sometimes hide the spines. Males are larger than females and have spurs on the inside of the hind limbs, near the foot.There is considerable variation in size and colour between the members of this genus, and even within each species, which sometimes makes identification difficult. Z. attenboroughi is much smaller than the other two species, and possesses a shorter beak and shorter fur. Z. bruijni is distinguished by the possession of three claws on the forefeet and hindfeet, whereas there are five claws on the forefeet of Z. bartoni and Z. attenboroughi.
Size: Head and body length: 450-775 mm
Weight: 5-10 kg
The most distinguishing feature of long-beaked echidnas is their long snouts, which curve downwards and account for two-thirds of the length of the head. They have no teeth; instead their tongues are covered in spikes (teeth-like projections), which are very effective in hooking prey and drawing it into the mouth. They have compact, muscular bodies, with strong limbs and claws for digging. Their back and sides are covered with spines, which vary in colour from white through to dark grey or black. The body is also covered in brownish-black hairs, which sometimes hide the spines. Males are larger than females and have spurs on the inside of the hind limbs, near the foot.There is considerable variation in size and colour between the members of this genus, and even within each species, which sometimes makes identification difficult. Z. attenboroughi is much smaller than the other two species, and possesses a shorter beak and shorter fur. Z. bruijni is distinguished by the possession of three claws on the forefeet and hindfeet, whereas there are five claws on the forefeet of Z. bartoni and Z. attenboroughi.
Ecology
Little is known of the ecology of long-beaked echidnas. They are thought to be largely nocturnal, spending the day resting in shallow burrows or hollow logs, and foraging amongst the forest litter at night for food. The diet consists almost exclusively of earthworms, although individuals may occasionally eat termites, insect larvae and ants. Echidnas lead solitary lives, coming together only to breed. This is thought to be seasonal, with the female laying 4-6 eggs into her pouch each July. Hatching occurs ten days later, and the young echidnas remain in the pouch for a further 6-7 weeks, or until the spines develop. All echidnas have the ability to erect their spines when they feel threatened. If the ground is soft, the animal will burrow into it to protect its belly. On hard ground it will curl up into a spiky ball like a hedgehog.
Habitat
Found at a variety of altitudes ranging from sea level to montane forests and highly elevated alpine meadows.
Distribution
Endemic to New Guinea, long-beaked echidnas are widespread and found in both Papua New Guinea in the west and Papua on the Indonesian side. They are also known from the island of Salawati off New Guinea’s western tip, and may possibly occur on the islands of Supiori and Waigeo, although their presence here has yet to be confirmed.The three species have distinct ranges: Z. bruijni is found in the far west of New Guinea, Z. attenboroughi is known only from the Cyclops Mountains of Papua, and Z. bartoni is principally found in a swathe along the centre of the island, where each of the 4 subspecies have separate ranges.
Little is known of the ecology of long-beaked echidnas. They are thought to be largely nocturnal, spending the day resting in shallow burrows or hollow logs, and foraging amongst the forest litter at night for food. The diet consists almost exclusively of earthworms, although individuals may occasionally eat termites, insect larvae and ants. Echidnas lead solitary lives, coming together only to breed. This is thought to be seasonal, with the female laying 4-6 eggs into her pouch each July. Hatching occurs ten days later, and the young echidnas remain in the pouch for a further 6-7 weeks, or until the spines develop. All echidnas have the ability to erect their spines when they feel threatened. If the ground is soft, the animal will burrow into it to protect its belly. On hard ground it will curl up into a spiky ball like a hedgehog.
Habitat
Found at a variety of altitudes ranging from sea level to montane forests and highly elevated alpine meadows.
Distribution
Endemic to New Guinea, long-beaked echidnas are widespread and found in both Papua New Guinea in the west and Papua on the Indonesian side. They are also known from the island of Salawati off New Guinea’s western tip, and may possibly occur on the islands of Supiori and Waigeo, although their presence here has yet to be confirmed.The three species have distinct ranges: Z. bruijni is found in the far west of New Guinea, Z. attenboroughi is known only from the Cyclops Mountains of Papua, and Z. bartoni is principally found in a swathe along the centre of the island, where each of the 4 subspecies have separate ranges.
Population Estimate
The population is estimated to be 300,000 individuals.
Population Trend
Decreasing in areas where they interact with humans.
Status
Only one species (Z. bruijni) is currently recognised by the IUCN. It is classified as Endangered (EN A1ac) on the 2006 IUCN Red List of Threatened Species.
Threats
Traditional hunting is the main reason for the species' decline. Long-beaked echidnas are highly prized game species and are hunted for food by local people with trained dogs. The other threats come from farming, logging and mining, which are causing a decline in the echidnas' forest habitat.Attenborough's long-beaked echidna was previously thought to be possibly extinct since it was apparently restricted to a single mountain peak in the Cyclops Mountains and hadn’t been reported since the original specimen was found in 1961. However, a recent EDGE expedition to the region found evidence that the species survives, even in the lowlands, and may have a larger range than previously believed. Very little is known about the threats to Attenborough's echidna, although interviews with local community members suggested that it is also at risk from hunting.
Conservation Underway
Z. bruijni is listed on Appendix II of CITES. It is fully protected in Papua, and partially protected in Papua New Guinea, although traditional hunting with dogs is still permitted there. Following recommendations made by the IUCN/SSC Australasian Marsupial and Monotreme Specialist Group, research into the reproductive cycle of the female is underway, in the hope that a captive breeding programme might be established at Taronga Zoo in Sydney, Australia.Z. attenboroughi occurs in the Cyclops Mountains Strict Nature Reserve, although it's conservation status is currently unknown, and it continues to be hunted for food.
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