Worldwide population estimates of large-carnivore species. Error bars represent the low and high range of the estimates when available. Population estimates were not available for all species. Species ranges vary widely, and range sizes can have a strong influence on species population levels (table S1). Sources: Gray wolf (90), all other species IUCN (91). Graphic: Ripple, et al., 2014 / DOI: 10.1126/science.1241484

Worldwide population estimates of large-carnivore species. Error bars represent the low and high range of the estimates when available. Population estimates were not available for all species. Species ranges vary widely, and range sizes can have a strong influence on species population levels (table S1). Sources: Gray wolf (90), all other species IUCN (91).

Maps showing the the spatial overlap for the ranges of large-carnivore species by threat category for habitat loss and fragmentation, persecution, utilization, and depletion of prey. Graphic: Ripple, et al., 2014 / DOI: 10.1126/science.1241484

Maps showing the the spatial overlap for the ranges of large-carnivore species by threat category for habitat loss and fragmentation, persecution, utilization, and depletion of prey.

The number of large-carnivore species affected by specific threats is shown in the map legend. Threat categories include:

(A) Habitat loss and fragmentation. Forest logging and/or the development of urban, agricultural, and road infrastructure reduces land available to large carnivores and creates barriers between and within populations.

(B) Persecution. Culling (poison baiting, trapping, and shooting) for the purpose of removal or reduction, in some cases reinforced with a government-subsidized bounty system, in response to real or perceived threat to pastoral and agricultural activities and human lives.

(C) Utilization. Large carnivores are killed for sport, body parts for traditional medicine, fur, and meat for human consumption, and live animals are captured and sold.

(D) Depletion of prey. The decline of prey populations due to human hunting, competition with livestock, habitat loss, and other factors reduces the prey base for large carnivores. See table S2 for raw data. Source: IUCN (91).

Family/species* Common name Mass, diet IUCN status (trend) % of historical range Reference for % of historical range
Canidae          
Canis lupus Gray wolf 33, M LC (stable) 67 (1)
Canis rufus Red wolf 25, M CR (increasing) <1 (91)
Chrysocyon brachyurus Maned wolf 23, O NT (unknown) 68 (2)
Lycaon pictus African wild dog 22, M EN (decreasing) 10 (17)
Cuon alpinus Dhole 16, M EN (decreasing)
Canis dingo Dingo 15, M VU (decreasing) 84 (20)
Canis simensis Ethiopian wolf 15, M EN (decreasing) 2 (17)
Felidae          
Panthera tigris Tiger 161, M EN (decreasing) 18 (3)
Panthera leo Lion 156, M VU (decreasing) 17 (17)
Panthera onca Jaguar 87, M NT (decreasing) 57 (3)
Acinonyx jubatus Cheetah 59, M VU (decreasing) 17 (17)
Panthera pardus Leopard 53, M NT (decreasing) 65 (3)
Puma concolor Puma 52, M LC (decreasing) 73 (3)
Panthera uncia Snow leopard 33, M EN (decreasing)
Neofelis nebulosa Clouded leopard 20, M VU (decreasing)
Neofelis diardi Sunda clouded leopard 20, M VU (decreasing)
Lynx lynx Eurasian lynx 18, M LC (stable)
Mustelidae          
Enhydra lutris Sea otter 28, M EN (decreasing)
Pteronura brasilliensis Giant otter 24, M EN (decreasing)
Aonyx capensis Cape clawless otter 19, M LC (stable)
Ursidae          
Ursus maritimus Polar bear 365, M VU (decreasing)
Ursus arctus Brown bear 299, O LC (stable) 68 (3)
Ailuropoda melanoleuca Giant panda 134, V EN (decreasing)
Ursus americanus American black bear 111, O LC (increasing) 59 (35)
Tremarctos ornatus Andean black bear 105, O VU (decreasing)
Ursus thibetanus Asiatic black bear 104, O VU (decreasing)
Melursus ursinus Sloth bear 102, O VU (decreasing)
Helarctos malayanus Sun bear 46, O VU (decreasing)
Hyaenidae          
Crocuta crocuta Spotted hyena 52, M LC (decreasing) 73 (17)
Hyaena brunnea Brown hyena 43, O NT (decreasing) 62 (17)
Hyaena hyaena Striped hyena 27, O NT (decreasing) 62 (17)

Large-carnivore species list, body mass (in kilograms), diet, endangerment status, population trend, and percent of historical range occupied.

Body masses are from Gittleman (15), Mammalian Species Accounts, and the Animal Diversity Web. Diet categories are from Hunter (1) as follows: M, meat eater; V, vegetation and/or fruit eater; O, omnivore. Species status and trend are from the IUCN Red List (16): LC, least concern; NT, near threatened; VU, vulnerable; EN, endangered; CR, critically endangered.

*Changes to taxonomic status have influenced the number of species included in this group, and some less-known and taxonomically ambiguous carnivores may be missing from this analysis because they have yet to be listed by the IUCN.

†Currently incorporates the New Guinea singing dog, C. hallstromi, whose taxonomic and conservation status is yet to be elucidated.

ABSTRACT: Large carnivores face serious threats and are experiencing massive declines in their populations and geographic ranges around the world. We highlight how these threats have affected the conservation status and ecological functioning of the 31 largest mammalian carnivores on Earth. Consistent with theory, empirical studies increasingly show that large carnivores have substantial effects on the structure and function of diverse ecosystems. Significant cascading trophic interactions, mediated by their prey or sympatric mesopredators, arise when some of these carnivores are extirpated from or repatriated to ecosystems. Unexpected effects of trophic cascades on various taxa and processes include changes to bird, mammal, invertebrate, and herpetofauna abundance or richness; subsidies to scavengers; altered disease dynamics; carbon sequestration; modified stream morphology; and crop damage. Promoting tolerance and coexistence with large carnivores is a crucial societal challenge that will ultimately determine the fate of Earth’s largest carnivores and all that depends upon them, including humans.

Status and Ecological Effects of the World’s Largest Carnivores

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