100 most endangered species: priceless or worthless? – in pictures

Rio Pescado stubfoot toad, Atelopus balios Population size: Unknown Range: Azuay, Cañar and Guyas provinces, south-western Ecuador Threats: Chytridiomycosis and habitat destruction due to logging and agricultural expansion Action required: Protection of last remaining habitat Photograph: Eduardo Toral-Contreras/ZSL/IUCN

Pygmy three-toed sloth, Bradypus pygmaeus Population size: 500 individuals Range: Approximately 1.3km2 – 1.5km2 on Isla Escudo de Veraguas, Panama Threats: Habitat loss due to illegal logging of mangrove forests for firewood and construction and hunting of the sloths Action required: Enforcement of protection of the Isla Escudo de Veraguas nature sanctuary and raising awareness Photograph: Craig Turner/ZSL/IUCN

Seychelles sheath-tailed bat, Coleura seychellensis Population size: 100 mature individuals Range: Two small caves on Silhouette and Mahé, Seychelles Threats: Habitat degradation and predation by invasive species Action required: Removal of invasive vegetation and control of introduced predators, coupled with legal protection of habitat and roosting sites Photograph: Picasa/ZSL/IUCN

Tarzan’s chameleon, Calumma tarzan Population size: Unknown Range: 10km2 in Anosibe An’Ala region, eastern Madagascar Primary threats: Habitat destruction for agriculture Action required: Support for nascent community conservation initiatives and protection of habitat Photograph: Frank Gaw/ZSL/IUCN

Wild yam, Dioscorea strydomiana Population size: 200 individuals Range: Oshoek area, Mpumalanga, South Africa Primary threats: Collection for medicinal use Action required: Develop strategy for sustainable use and establish ex-situ populations Photograph: ZSL/IUCN

Spoon-billed sandpiper, Eurynorhyncus pygmeus Population size: 100 breeding pairs Range: Breeds in Russia, migrates along the East Asian-Australasian Flyway to wintering grounds in Bangladesh and Myanmar. Primary threats: Trapping on wintering grounds and land reclamation. Actions required: Maintenance of critical intertidal staging posts and reducing trapping on wintering grounds. Photograph: Baz Scampion/ZSL/IUCN

Jamaican iguana, Cyclura collei Population size: Unknown Range: 10km2 in Hellshire Hills, Jamaica Primary threats: Predation by introduced species and habitat destruction Action required: Translocation to predator-free islands and control of deforestation Photograph: ZSL/IUCN

Hirola, Beatragus hunteri Population size: 1,000 individuals Range: South-east Kenya and possibly south-west Somalia Primary threats: Habitat loss and degradation, competition with livestock, poaching Action required: Establishment of protected areas and community conservancies, increase in level of management and protection of wild population Photograph: ZSL/IUCN

Araripe manakin, Antilophia bokermanni Population size: 779 individuals Range: 28km2, Chapado do Araripe, South Ceará, Brazil Primary threats: Habitat destruction due to expansion of agriculture and recreational facilities and water diversion Actions required: Formal protection of remaining habitat and protection of springs and streams Photograph: ZSL/IUCN

Santa Catarina’s guinea pig, Cavia intermedia Population size: 40-60 individuals Range: 0.04km2 on Moleques do Sul Island, Santa Catarina, Brazil Primary threats: Habitat disturbance and possible hunting; small population effects Action required: Protected area enforcement and regulation of access to the island Photograph: Luciano Candisani/ZSL/IUCN

Sumatran rhino, Dicerorhinus sumatrensis Population size: 250 mature individuals Range: Sabah, Sarawak and Peninsular Malaysia, Kalimantan and Sumatra, Indonesia Primary threats: Hunting for horn - used in traditional medicine Action required: Expansion and reinforcement of anti-poaching programmes and continuation of captive breeding efforts Photograph: ZSL/IUCN

Euphorbia tanaensis Population size: 4 mature individuals Range: Witu Forest Reserve, Kenya Primary threats: Illegal logging and habitat degradation due to agricultural expansion and infrastructure development Action required: Enforcement of legal protection in the Witu forest reserve, which has diminished due to civil insecurity Photograph: Olivier Hamerlynck/ZSL/IUCN

Amsterdam albatross, Diomedea amsterdamensis Population size: 100 mature individuals Range: Breeds on Plateuau des Tourbières, Amsterdam Island, Indian Ocean. Primary threats: Disease and incidental by-catch in long-line fishing operations Action required: Prevention of the spread of disease and promotion of best-practice measures in all fisheries within the species range Photograph: ZSL/IUCN

Sakhalin taimen, Hucho perryi Population size: Unknown Range: 233,498km2, Russian far east and northern Japan Primary threats: Overfishing (sport fishing and commercial bycatch) and habitat loss from damming, agriculture and other land-use practices Action required: Expansion of conservation protection in rivers in Russia and Japan and enforcement of fishing regulations Photograph: Sarafutsu Itou no Kai/ZSL/IUCN

Coral tree, Erythrina schliebenii Population size: 50 individuals Range: Namatimbili-Ngarama Forest, Tanzania Primary threats: Limited habitat and small population size increasing vulnerability to stochastic events Actions required: Complete establishment of forest reserves and continue propagation efforts, ex-situ conservation Photograph: ZSL/IUCN

Geometric tortoise, Psammobates geometricus Population size: Unknown Range: Western Cape Province, South Africa Primary threats: Habitat destruction and degradation, and predation Action required: Establishment of additional reserves and management of fire regimes Photograph: ZSL/IUCN

Tonkin snub-nosed monkey, Rhinopithecus avunculus Population size: < 200 individuals Range: Northeastern Viet Nam Primary threats: Habitat loss and hunting Action required: Establishment of a conservation area for Khau Ca Conservation area in Ha Giang province and increase law enforcement to reduce hunting pressure Photograph: LeKhacQuyet/ZSL/IUCN

Bullock’s false toad, Telmatobufo bullocki Population size: Unknown Range: 500km2, Nahuelbuta, Arauco Province, Chile Primary threats: Habitat destruction as a result of construction of a hydro-electricity scheme Actions required: Halting development of the hydro-electricity scheme and protecting habitat Photograph: ZSL/IUCN

Rosa arabica Population size: unknown, 10 sub-populations Range: 14.6km2, St Katherine Mountains, Egypt Primary threats: Domestic animals grazing, climate change and drought, medicinal plant collection and restricted range Action required: Protection of individuals from exploitation Photograph: Medicinal Plant Conservation Project Egypt and St Katherine Park/ZSL/IUCN

Red-finned blue-eye, Scaturiginichthys vermeilipinnis Population size: 2,000 - 4,000 individuals Range: Edgbaston Station, central western Queensland, Australia Threats: Predation by introduced species Action required: Control of the invasive species Gambusia holbrooki, and reintroduction of the species Photograph: Adam Kerezsy/ZSL/IUCN

Okinawa spiny rat, Tokudaia muenninki Population size: Unknown Range: 3km2 on Okinawa Island, Japan Primary threats: Habitat loss and predation by feral cats Action required: Surveys to map species range, protection of remaining habitat and feral cat control programme Photograph: ZSL/IUCN

Cebu frill-wing, Risiocnemis seidenschwarzi Population size: Unknown Range: In a single rivulet beside the Kawasan River, Cebu, Philippines Primary threats: Habitat degradation and destruction Actions required: Designation of area as critical habitat – restricting human access to the area Photograph: ZSL/IUCN

Red River giant softshell turtle, Rafetus swinhoei Population size: Four individuals Range: Hoan Kiem Lake and Dong Mo Lake, Vietnam, and Suzhou Zoo, China Primary threats: Hunting for consumption, habitat destruction, degradation as a result of wetland destruction and pollution Actions required: Education and awareness programmes, and captive breeding Photograph: Doug Hendrie/Wildlife Conservation Society/PA

Saola, Pseudoryx nghetinhensis Population size: Unknown Range: Annamite mountains, on the Vietnam/Laos border Threats: Hunting and habitat destruction Action required: Increase enforcement efforts and habitat protection Photograph: WWF/AP

Greater bamboo lemur, Prolemur simus Population size: 100-160 individuals Range: South-eastern and central rainforests of Madagascar Primary threats: Habitat destruction due to slash-and-burn agriculture, mining and illegal logging Action required: Habitat protection and reforestation in the Ivato and Karlanaga regions Photograph: ZSL/IUCN

Luristan newt, Neurergus kaiseri Population size: 1,000 mature individuals Range: Zagros Mountains, Lorestan, Iran Primary threats: Illegal collection for pet trade Action required: Enforcement of protection Photograph: unknown/ZSL/IUCN

Vaquita, Phocoena sinus Population size: 200 individuals and declining Range: Northern Gulf of California, Mexico Primary threats: Incidental capture in gillnets Actions required: Ban on use of gillnets throughout the species’ range Photograph: Omar Vidal/WWF/REUTERS

Attenborough’s pitcher plant, Nepenthes attenboroughii Population size: Unknown Range: Mount Victoria, Palawan, Philippines Primary threats: Poaching Actions required: Creation of a protected area and enforcement of current legal protection Photograph: ZSL/IUCN

Great Indian bustard, Ardeotis nigriceps Population size: 50 - 249 mature individuals Range: 570,000km2 in Rajasthan, Gujarat, Maharashta, Andhra Pradesh, Karnataka and Madhya, India Primary threats: Habitat loss and modification due to agricultural development Action required: Establishment of protected areas and community reserves, and realignment of Indira Ghandi Nahar Canal Project Photograph: Rahul Sachdev/ZSL/IUCN