Animal Info - World's Rarest Mammals

Mammal species with published estimates of worldwide population about 1000 animals* or less (animals are listed in the order of their population estimates, with the rarest listed first). (*P) indicates that there are one or more links to pictures of the animal in the "Profile" section at the top of its web page.

• Baiji (Yangtze River Dolphin) (*P) - ... maybe no more than a few tens of individuals... (Reeves et al. 2003)
• Vancouver Island Marmot (*P) - ...29... (Vanc. Is. Marm. Recov. Found. 2005)
• Seychelles Sheath-tailed Bat (*P) - ...50 - 100 individuals... (IUCN 2004)
• Javan Rhino (*P) - ...about 60... (Intl. Rhino Found. 2005)
• Hispid Hare (Assam Rabbit) (*P) - ...110... (Kavitha 2001)
• Northern Hairy-nosed Wombat (*P) - ...113... (Queensland Parks Wildl. Serv. 2003)
• Tamaraw (Dwarf Water Buffalo) (*P) - ...the total population is thought to be about 30 - 200... (IUCN 2003a)
• Iberian Lynx (*P) - ...As few as 120... (FFI Update 2006)
• Red Wolf (*P) - ...less than 150 (re-introduced) ... (IUCN 2004)
• Dwarf Blue Sheep (*P) - ...approximately 200... (Wang et al. 2000)
• Yellow-tailed Woolly Monkey (*P) - ...fewer than 250 individuals... (IUCN 2003a)
• Kouprey (Cambodian Forest Ox) (*P) - ...generally assumed to be less than 250... (IUCN 2003a)
• Riverine Rabbit (*P) - ...About 250 adults... (Flux 2005)
• Malabar Large Spotted Civet (*P) - ...fewer than 250 mature individuals are thought to survive... (Nowak 1999)
• Saola (Vu Quang Ox) (*P) - ...estimated at less than 250 mature individuals... (IUCN 2006)
• Tonkin Snub-nosed Monkey (*P) - ...less than 300... (IUCN 2003a)
• Sumatran Rhino (*P) - ...about 300... (Intl. Rhino Found. 2005)
• Northern Muriqui - ...less than 300... (IUCN 2003a)
• Visayan Spotted Deer (*P) - ...a few hundred... (Heaney and Regalado 1998)
• Hirola (Hunter's Hartebeest) (*P) - ...by 1995 numbers were down to 300... (Kingdon 1997)
• Addax (*P) - ...may not exceed a few hundred individuals... (Mallon & Kingswood 2001)
• North Atlantic Right Whale (*P) - ...around 350... (Focus 2004a)
• Black-faced Lion Tamarin (*P) - ...as few as 400... (Natl. Zoo Cons. Sci. 2004)
• Ethiopian Wolf (*P) - ...at least 442... (Sillero-Zubiri & Marino 2004)
• Black-footed Ferret (*P) - ...about 500 in the wild... (Focus 2005a)
• African Wild Ass (*P) - ...less than 570... (Moehlman 2002a)
• Vaquita (*P) - ...less than 600... (Oryx 2004d)
• Arabian Oryx (*P) - ...Approximately 886 (re-introduced)... (IUCN 2004)
• Mediterranean Monk Seal (*P) - ...an estimated 500 individuals... (Karamanlidis et al. 2004)
• Bactrian Camel (*P) - ...approximately 950... (IUCN 2003a)
• Hairy-eared Dwarf Lemur (*P) - ...estimated to number between 100 - 1000... (IUCN 2002)
• Southern Muriqui (Woolly Spider Monkey) (*P) - ...does not exceed 1000... (IUCN 2003a)
• Golden Bamboo Lemur (*P) - ...about 1000 individuals... (IUCN 2002)
• Golden-rumped Lion Tamarin (*P) - ...1000... (Natl. Zoo Cons. Sci. 2004)
• Greater Bamboo Lemur (*P) - ...1000 individuals... (IUCN 2003a)
• Indus River Dolphin (*P) - ...At least 1000... (Focus/WWF 2001)

Graduates of 'World's Rarest Mammals'

• Golden Lion Tamarin
• Giant Panda

*Notes:

1. There are many other mammals with populations less than 1000 animals for which population estimates are not available.
2. Only wild populations are meant to be included.
3. Many of the population numbers are rough estimates. However, as Schaller has noted: "...even a well-considered guess has validity when evaluating status of endangered species." (Schaller 1998, p. 202)