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Endangered Species series main post.

Mammals (class: Mammalia) are a taxonomic group broadly defined by their milk-producing mammary glands, possession of hair and three ossicles in the middle ear. They also uniquely possess a neocortex; the area of the brain involved in higher functions. Most mammals give birth to live young though this is not true of the monotremes – platypus (Ornithorhynchidae) and echidna (Tachyglossidae) – which lay eggs. It is a relatively small taxa with only around 6,000 described species. These species range in size from Kitti’s hog-nosed bat (Craseonycteris thonglongyai) at 30-40mm and the Etruscan shrew (Suncus etruscus) which weighs only 1.8 grams, to the blue whale (Balaenoptera musculus) which with a length of 33m and a weight of 180 tons is the most massive animal known to have existed. True mammals first appeared in the Triassic when they exploited niches available to small, nocturnal predators. The group does not seem to have diversified much beyond these niches (though taxonomic orders were largely already in place) until the end of the reign of the dinosaurs c. 65 million years ago when they rapidly evolved to fill larger niches.

[1] Wund, M., Myers., P. (2005). Mammalia. Animal Diversity Web. [online]
[2] Tree of Life Web Project (1995). Mammalia. Mammals. Version 01 January 1995 (temporary). [online]
[3] Kumar, V. (2011). Mammalia. Encyclopedia of Life. [online]

Bawean deer (Axis kuhlii)
Little studied, this small deer inhabits dense upland forests of Bawean Island, Indonesia, an area of 200km2. This represents the most restricted range of any deer species. Morphologically similar to the India’s closely related hog deer, they are a little-seen species due to their largely nocturnal habits. The total wild population is thought to be around 250 individuals. Predators including wild pigs, macaques and pythons may account for some individuals but their impact is likely to be minimal. Feral dogs pose a far greater threat and, along with habitat loss and a decline in habitat quality, are the main causes of continued decline.

[1] Semiadi, G., Pudyatmoko, S., Duckworth, J.W. & Timmins, R.J. 2008. Axis kuhlii. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4
[2] ARKive (2010). Bawean deer (Axis kuhlii). [online]
[3] Huffman, B. (2011). Axis kuhlii. Ultimateungulate.com. [online]
Image © Midori

Cozumel Raccoon (Procyon pygmaeus)
Also called the ‘Pygmy raccoon’, P. pygmaeus is much smaller and occurs over a far smaller range than its better-known cousin, the common raccoon (Procyon lotor). Their insular dwarfism is due to their isolation and evolution on Cozumel Island, Mexico. P. pygmaeus is thought to exhibit more specific ecological requirements than P. lotor and island-raccoon subspecies. They prefer mangrove and wetland habitats where they forage for crabs and shellfish. Such specificity in an island species inevitably limits the extent of occurrence (478km2) and population size. Indeed, there are fewer than 250 mature individuals remaining. Anthropogenic factors and the impact of hurricanes – which can account for 60% of juveniles – pose the greatest threats.

[1] Cuarón, A.D., de Grammont, P.C., Vázquez-Domínguez, E., Valenzuela-Galván, D., García-Vasco, D., Reid, F. & Helgen, K. 2008. Procyon pygmaeus. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] McFadden, K.W., Sambrotto, R.N., Medellin, R.A., Gompper, M.E. (2006). Feeding habits of endangered pygmy raccoons (Procyon pygemaeus) based on stable isotope and fecal analysis. Journal of Mammalogy. 87(3):501-509 [available online]

Maui’s dolphin (Cephalorhynchus hectori maui)
A subspecies of Hector’s dolphin, Maui’s dolphin (originally called the North Island Hector’s dolphin) is found along the West coast of North Island, New Zealand. They are largely threatened by gillnet and trawl fisheries where it they are caught as bycatch, pollution, boat strikes and inbreeding. Maui’s conform to the common dolphin stereotypes of sociability and playfulness, grouping in pods over five strong. They have a slow reproductive cycle with females calving every 2-4 years and then only producing a single offspring. Approximately 111 individuals remain. Only 28 of these are likely to be mature females.

[1] Reeves, R.R., Dawson, S.M., Jefferson, T.A., Karczmarski, L., Laidre, K., O’Corry-Crowe, G., Rojas-Bracho, L., Secchi, E.R., Slooten, E., Smith, B.D., Wang, J.Y. & Zhou, K. 2008. Cephalorhynchus hectori ssp. maui. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4
[2] Slooten, E., Dawson, S.M. (2008). Sustainable levels of human impact for Hector’s dolphin. The Open Conservation Biology Journal. 2:37-43. [available online]
[3] New Zealand Ministry of Fisheries and Department of Conservation (2007). Hector’s dolphin threat management discussion document. [available online]
Image © Will Rayment

Visayan Warty Pig (Sus cebifrons)
S. cebifrons
is a gregarious pig which is endemic to the Visayan island chain – more specifically the islands of Panay, Negros and possibly Masbate – in the Philippines. The species are easily distinguished by the white band running laterally across the top of the nose which is present in both sexes. Little is known of their ecology though it is likely that in ideal circumstances it is an overall generalist. The remaining populations are fragmented, having been extirpated in 95% of the historical range by slash-and-burn agriculture, logging, hunting and hybridisation with feral animals. The species are nationally protected though enforcement is poor. The number of surviving individuals is unknown.

[1] Oliver, W. 2008. Sus cebifrons. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] Huffman, B. (2011). Sus cebifrons. Ultimateungulate.com [online]
Image © B. Gratwicke

Malabar Large-spotted Civet (Viverra civettina)
With a declining population numbering fewer than 250 mature individuals fragmented into sub-populations of fewer than 50 individuals in total, the Malabar Large-Spotted Civet is one of the planet’s most endangered mammals. Found in the Western Ghats, India, its favoured habitats of lowland swamps and forests have been completely removed. This forces the species to utilise previously undesirable degraded or secondary habitat and thickets in cashew plantations. Conflict with humans is a severe threat as the species will opportunistically raid for poultry. It does not currently exist within any protected areas.

[1] Jennings, A., Veron, G. & Helgen, K. 2008. Viverra civettina. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4
[2] Schreiber, A., Wirth, R., Riffel, M., van Rompaey, H. (1989). Weasels, civets, mongooses and the relatives: An action plan for the conservation of mustelids and viverrids. IUCN/SSC Mustelid and Viverrid Specialist Group. [available online]
[3] Animal Info (2005). Viverra civettina (V Megaspila c.). [online]

Seychelles sheath-tailed bat (Coleura seychellensis)
Sheath-tailed bats are so-called due to the projection of the short tail through the tail membrane which effectively forms a sheath. The species is found on the islands of Silhouette, Mahe and Praslin in the Seychelles. There appears to have been several precipitous population declines; in the late 1800′s – 1900′s during the clearing of lowland forests and again since the 1970′s when the species was apparently common. It is now thought that there are fewer than 100 mature individuals remaining. Habitat loss for invertebrate prey, loss of roost sites and predation by introduced species are evident threats.

[1] Gerlach, J., Mickleburgh, S., Hutson, A.M. & Bergmans, W. 2008. Coleura seychellensis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] ARKive.org (2011). Seychelles sheath-tailed bat  (Coleura seychellensis). [online]
[3] Gerlach, J. (2007). Vocalisations of the Seychelles sheath-tailed bat Coleura seychellensis. Le Rhinolophe 18:xx-xx. [available online]

Northwest African Cheetah (Acinonyx jubatus hecki)
This sub-species exhibits a limited distribution in northwest Africa, specifically Algeria, Niger, Benin and Burkina Faso. Though very little is known about the species, it probably mirrors the ecology and life histories of other A. jubatus subspecies. There exists no sub-population of more than 50 mature individuals; the total number of mature individuals is thought to be fewer than 250 animals.

[1] Belbachir, F. 2008. Acinonyx jubatus ssp. hecki. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
Image © Farid Belbachir

Giant Sable Antelope (Hippotragus niger variani)
The Giant Sable is endemic to Angola where it inhabits the area between the Kwango and Luando rivers. This secretive species cuts a striking figure due to their large curved horns which are present in both sexes (though male horns are longer and more curved). They exhibit a preference for forest and associated riparian habitats where they a specific and preferential browsers. The population has declined and fragmented largely due to long-term military conflict and hunting; only 200-400 individuals remain. It is possible that a viable population (>50 individuals) exists within Luando Strict Reserve. Hybridisation with Roan antelope (H. equinus) is a current threat.

[1] IUCN SSC Antelope Specialist Group 2008. Hippotragus niger ssp. variani. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4
[2] Huffman, B. (2004). Hippotragus niger. Ultimateungulate.com. [online]

Dwarf Hutia (Mesocapromys nanus)
This species was thought to be extinct until an extant population was discovered. No specimens have been recorded since 1937 when the species was restricted to Zapata Swamp, Cuba. Introduced rats and mongooses and habitat destruction may have resulted in the extinction of the species some time ago. However, reports of tracks and droppings suggest that a small population may persist.

[1] Soy, J. & Silva, G. 2008. Mesocapromys nanus. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
Image depicts Demarest’s hutia (Capromys pilorides)

Brush-tailed bettong (Bettongia penicillata)
The brush-tailed bettong (or, to give it its Australian moniker, Woylie) belongs to the marsupial family Macropodidae which also includes kangaroos, wallabies and the like. Though it was once more widespread and could be found in a variety of habitats, it is now restricted to dry forest understory around Alice Springs, Western Australia. Despite conservation efforts, the species has continued to decline with some small populations disappearing altogether. There are translocated populations in Western Australia, New South Wales and South Australian islands which exhibit varying degrees of success.

[1] Wayne, A., Friend, T., Burbidge, A., Morris, K. & van Weenen, J. 2008. Bettongia penicillata. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] ARKive.org (2011). Brush-tailed bettong  (Bettongia penicillata). [online]
[3] Start, A.N., Burbidge, A.A., Armstrong,  D. (1995). Woylie recovery plan Wildlife Management Program. 16. State Recovery Plan. [available online]
Image © Gary Lewis

Yellow-tailed Woolly Monkey (Oreonax flavicauda)
The Yellow-tailed Woolly Monkey can be found in montane and cloud forest habitats of San Martin and Amazons in the Peruvian Andes. Originally described from a skin in the early 1800′s, it was re-discovered in 1974 (and anyone wishing to delve into this species’ history should note that it was reassigned from the genus Lagothrix to Oreonax in the early 2000′s). Since this time, the species has suffered a significant population decline as its previously inaccessible habitat was opened up by colonisation projects, road building, logging and other such projects. Habitat loss is a continued threat as is subsistence hunting by natives. Current population numbers are unknown.

[1] Cornejo, F., Rylands, A.B., Mittermeier, R.A. & Heymann, E. 2008. Oreonax flavicauda. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4
[2] Mittermeier, R.A., Wallis, J., Rylands, A.B. et al., eds (2009). Primates in Peril: The World’s 25 Most Endangered Primates 2008–2010. Illustrated by S.D. Nash. Arlington, VA.: IUCN/SSC Primate Specialist Group (PSG), International Primatological Society (IPS), and Conservation International (CI). pp. 1–92. [available online]
[3] Buckingham, F., Shaneee., S. (2009). Conservation priorities for the Peruvian yellow-tailed woolly monkey (Oreonax flavicauda): a GIS risk assessment and gap análysis. Primate Conservation (24). [available online]
Image © Platyrhinnus

Iriomote cat (Prionailurus iriomotensis)
This extremely rare and elusive species is endemic to the 284km2 Japanese island of Iriomote, 200km off the coast of Taiwan. Despite the largely mountainous evergreen nature of the island, the cat apparently favours lowland wetland, streams and small hills. Loss of this lowland habitat over the course of the last decade may have resulted in population decline. There are fewer than 100 individuals remaining though the population is contiguous.

[1] Izawa, M. 2008. Prionailurus bengalensis ssp. iriomotensis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] Okamura, M., Doi, T., Sakaguchi, N., Izawa, M. (2000). Annual reproductive cycle of the Iriomote cat Felis iriomotensis. Mammal study. 25:75-85. [available online]

Pygmy three-toed sloth (Bradypus pygmaeus)
B. pygmaeus
is thought to have diverged from the mainland brown-throated sloth (B. variegatus) lineage when the island of Escudo de Veraguas split from the Panamanian mainland c. 8900 years ago. The species seems to exist on nutritionally poor red mangrove leaves. Its island home is less than 5km2; what little habitat it supports is declining is quality. There is no information available on its population status.

[1] Samudio, R. & Members of the IUCN SSC Edentate Specialist Group 2008. Bradypus pygmaeus. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] Anderson, R. P., Handley, C. O., Jr. (2001). A new species of three-toed sloth (Mammalia: Xenarthra) from Panama, with a review of the genus Bradypus. Proceedings of the Biological Society of Washington 114(1):1–33. [available online]
Image © Bryson Voirin

Riverine Rabbit (Bunolagus monticularis)
The Riverine rabbit, probably the most endangered lagomorph in the world, is endemic to the Karoo region of South Africa. Its population has been severely fragmented due to anthropogenic impacts on the landscape. These factors have also served to isolate the remaining sub-populations, limiting or omitting effective gene flow. Though the rate of habitat loss has been arrested, hunting and accidental snaring does occur and the remaining population may become extinct within 50 years without intervention. There are fewer than 250 breeding pairs remaining.

[1] South African Mammal CAMP Workshop 2008. Bunolagus monticularis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
[2] ARKive.org (2011). Riverine rabbit  (Bunolagus monticularis). [online]
Image © van Dyke