endangered species

An endangered species is a population of organisms (usually a taxonomic species), which because it is either (a) few in number or (b) threatened by changing environmental or predation parameters, is at risk of becoming extinct. Many countries have laws offering special protection to these species or their habitats: for example, forbidding hunting, restricting land development or creating preserves. Only a few of the many endangered species actually make it to the lists and obtain legal protection. Many more species become extinct, or potentially will become extinct, without gaining public notice.

The greatest factor of concern is the rate at which species are becoming extinct within the last 150 years. While species have evolved and become extinct on a regular basis for the last several hundred million years, the number of species becoming extinct since the Industrial Revolution has no precedent in biological history. If this rate of extinction continues, or accelerates as now seems to be the case, the number of species becoming extinct in the next decade could number in the millions^[1]. While most people readily relate to endangerment of large mammals or birdlife, some of the greatest ecological issues are the threats to stability of whole ecosystems if key species vanish at any level of the food chain.

Issues of extinction

Main article: Extinction

Species extinction is the ultimate concern, but there are four different reasons to have for concern with this outcome:

1. Loss of a species as a biological entity
2. Destabilization of an ecosystem
3. Endangerment of other species
4. Loss of irreplaceable genetic material and associated biochemicals

The loss of a species in and of itself is an important factor, both as diminution of the enjoyment of nature and as a moral issue for those who believe humans are stewards of the natural environment. Destabilization is a well understood outcome, when an element of food or predation is removed from an ecosystem. Examples abound that other species are in turn affected, such that population increases or declines are forthcoming in these secondary species. Drastic change or an unstable spiral can ensue, until other species are lost and the ecosystem structure is changed markedly and irreversibly.

The fourth outcome is more subtle, but perhaps the most important point for mankind to grasp. Each species carries unique genetic material in its DNA and in its chemical factory responding to these genetic instructions. For example, in the valleys of central China, a fernlike weed called sweet wormwood grows, that is the only source of artemisinin, a drug that is nearly 100 percent effective against malaria (Jonietz, 2006). If this plant were lost to extinction, then the ability to control malaria, even today a potent killer, would diminish. There are countless other examples of chemicals unique to a certain species, whose only source is the species, whose genetic factory makes that given substance. How many further chemicals have not yet been discovered and could vanish from the planet when further species become extinct cannot be determined, but it is a highly debated and influential point.

Though extinction can be a natural effect of the process of natural selection, the current extinction crisis is not related to that process. At the present, the Earth has fallen from a peak of biodiversity[1] and Earth is undergoing the Holocene mass extinction period.[2] These periods have occurred before without human intervention; however the current extinction period is unique. Previous periods were triggered by physical causes, such as meteorite collision and volcanic eruption, all leading to climate change. The current extinction period is being caused by humans and began approximately 100,000 years ago with the diaspora of humans to different parts the world. By entering new ecosystems which had never before experienced the human presence, humans disrupted the ecological balance by hunting and also possibly bringing disease. From this time up to approximately 10,000 years ago is known as "phase one" of the sixth extinction period.

Phase two of the period began approximately 10,000 years ago with the birth of agriculture. With the birth of agriculture, humans did not have to rely on interaction with other species for survival and so could begin to domesticate them, and they also did not have to adhere to the limitations of the ecosystem's carrying capacity. Thus, humans became the first species able to live outside local ecosystems. As Niles Eldridge says "Indeed, to develop agriculture is essentially to declare war on ecosystems - converting land to produce one or two food crops, with all other native plant species all now classified as unwanted "weeds" -- and all but a few domesticated species of animals now considered as pests."[3] With the ability to live outside of a local ecosystem, humans have been free to breech the "carrying-capacity" of areas and overpopulate, putting ever more stress on the environment with destructive activities necessary for more population growth. Today, those activities include tropical deforestation, coral loss, other habitat destruction, overexploitation of species, introduction of alien species into ecosystems and pollution (such as soil contamination and greenhouse gases).

Conservation status

The conservation status of a species is an indicator of the likelihood of that endangered species continuing to survive. Many factors are taken into account when assessing the conservation status of a species; not simply the number remaining, but the overall increase or decrease in the population over time, breeding success rates, known threats, and so on. In many areas this is referred to as a red-listed species. Internationally, 189 countries have signed an accord agreeing to create Biodiversity Action Plans to protect endangered and other threatened species. In the USA this plan is usually called a species Recovery Plan.

The best-known worldwide conservation status listing is the IUCN Red List, but many more specialized lists exist. The following conservation status categories are used in articles in this encyclopedia. They are loosely based on the IUCN categories.

• Extinct: the last remaining member of the species had died, or is presumed beyond reasonable doubt to have died. Examples: Thylacine, Dodo, Passenger Pigeon.
• Extinct in the wild: captive individuals survive, but there is no free-living, natural population. Examples: Dromedary.
• Critical or critically endangered: faces an extremely high risk of extinction in the immediate future. Examples: Ivory-billed Woodpecker, Arakan Forest Turtle
• Endangered: faces a very high risk of extinction in the near future. Examples: Blue Whale, Snow Leopard, Kings holly
• Vulnerable: faces a high risk of extinction in the medium-term. Examples: Cheetah, Bactrian Camel
• Secure or lower risk: no immediate threat to the survival of the species. Examples: Norway Rat, Nootka Cypress, Llama

The following lists are examples of endangered species. It is important to stress that the following lists are a miniscule fraction of the total endangered species. It is also worth noting that the number of species becoming extinct each year is many times as large as the number of species classified as endangered; this fact arises from the extensive and slow review process for listing new species as endangered. It also arises from the loluminous number of yearly extinctions, often for species about which little docementation exists. Note that because of varying standards for regarding a species as endangered, and the very large number of endangered species, these lists should not be regarded as comprehensive.

Endangered mammals

The following list is a very small fraction of known endangered mammals:

• Asian Elephant (Elephas maximus)
• Aye-aye (Daubentonia madagascariensis)
• Banteng (Bos javanicus)
• Bighorn Sheep (Ovis canadensis)
• Black Rhinoceros (Diceros bicornis)
• Black-footed Ferret (Mustela nigripes)
• Black-tailed Prairie Dog (Cynomys ludovicianus)
• Blue Whale (Balaenoptera musculus)
• Bonobo (Pan paniscus)
• Bornean Orangutan (Pongo pygmaeus)
• Burrowing Bettong (Bettongia lesueur nova)
• Common Chimpanzee (Pan troglodytes)
• Chinese River Dolphin (Lipotes vexillifer) and other river dolphins
• Diademed Sifaka (Propithecus diadema)
• Eastern Gorilla (Gorilla beringei)
• Fin Whale (Balaenoptera physalus)
• Forest Elephant (Loxodonta cyclotis)
• Fossa (Cryptoprocta ferox)
• Gelada (Theropithecus gelada)
• Giant golden-crowned flying fox (Acerodon jubatus)
• Giant Panda (Ailuropoda melanoleuca)
• Giant Pangolin (Manis gigantea)
• Giant Sable Antelope (Hippotragus niger varani)
• Golden Lion Tamarin (Leontopithecus rosalia)

• Gray Bat (Myotis grisescens)
• Hawaiian Monk Seal (Monachus schauinslandi)
• Humpback Whale (Megaptera novaeangliae)
• Iberian Lynx (Lynx pardinus)
• Indian Pangolin (Manis crassicaudata)
• Indri (Indri indri)
• Island Fox (Urocyon littoralis)
• Javan Rhinoceros (Rhinoceros sondaicus)
• Key Deer (Odocoileus virginianus clavium)
• Kouprey (Bos sauveli)
• Leopard (Panthera pardus)
• Mahogany Glider (Petaurus gracilis)
• Mountain Pygmy Possum (Burramys parvus)
• Northern Hairy-nosed Wombat (Lasiorhinus krefftii)
• Numbat (Myrmecobius fasciatus)

• Père David's Deer (Elaphurus davidianus)
• Proboscis Monkey (Nasalis larvatus)
• Red Panda (Ailurus fulgens)
• Red Wolf (Canis rufus)
• Savannah Elephant (Loxodonta africana)
• Sea Otter (Enhydra lutris)
• Sei Whale (Balaenoptera borealis)
• Snow Leopard (Uncia uncia)
• Steller's Sea Lion (Eumetopias jubatus)
• Sumatran Orangutan (Pongo abelii)
• Sumatran Rhinoceros (Dicerorhinus sumatrensis)
• Temminck's Pangolin (Manis temminckii)
• Tibetan Antelope (Pantholops hodgsonii)
• Tiger (Panthera tigris)
• Timber Wolf (Canis lupus)
• Vaquita (Phocoena sinus)
• Western Gorilla (Gorilla gorilla)
• West Indian Manatee (Trichechus manatus)
• Wolverine (Gulo gulo)

Endangered birds

• Alaotra Grebe (Tachybaptus rufolavatus)
• Andean Condor (Vultur gryphus)
• Amami Thrush (Zoothera major)
• Amsterdam Albatross (Diomedea amsterdamensis)
• Attwater's prairie-chicken (Tympanuchus cupido attwateri)
• Bali Starling (Leucospar rothschildi)
• Black-capped Petrel (Pterodroma hasitata)
• Bornean Peacock Pheasant (Polyplectron schleiermacheri)
• Brazilian Merganser (Mergus octosetaceus)
• California Clapper Rail (Rallus longirostris obsoletus)
• California Least Tern (Sterna antillarum browni)
• California Condor (Gymnogyps californianus)
• Chatham Albatross (Thalassarche eremita)
• Chinese Crested Tern (Sterna bernsteinii)
• Christmas Island Frigatebird (Fregata andrewsi)
• Cozumel Thrasher (Toxostoma guttatum)
• Crested Ibis (Nipponia nippon)
• Eskimo Curlew (Numenius borealis)
• Giant Ibis (Thaumatibis gigantea)
• Glaucous Macaw (Anodorhynchus glaucus)
• Guam Rail (Gallirallus owstoni)
• Gurney's Pitta (Pitta gurneyi)
• Hawaiian Crow (Corvus hawaiiensis)
• Hawaiian Goose or Néné (Branta sandvicensis)
• Imperial Woodpecker (Campephilus imperialis)
• Indian White-rumped Vulture (Gyps bengalensis)
• Ivory-billed Woodpecker (Campephilus principalis)
• Jerdon's Courser (Rhinoptilus bitorquatus)
• Junin Flightless Grebe (Podiceps taczanowskii)
• Kagu (Rhynochetos jubatus)
• Kakapo (Strigops habroptilus)
• Kittlitz's Murrelet (Brachyramphus brevirostris)
• Kiwi (Apteryx australis, A. hastii, A. owenii)
• Laysan Duck (Anas laysanensis)
• Lear's Macaw (Anodorhynchus leari)
• Long-billed Vulture (Gyps indicus)
• Magdalena Tinamou (Crypturellus saltuarius)
• Magenta Petrel (Pterodroma magentae)
• Maleo (Macrocephalon maleo)
• Mauritius Fody (Foudia rubra)
• Mauritius Parakeet (Psittacula eques)
• Mindoro Bleeding-heart (Gallicolumba platenae)
• New Zealand Storm-petrel (Oceanites maorianus)
• Night Parrot (Geopsittacus occidentalis)
• Northern Bald Ibis (Geronticus eremita)
• Okinawa Woodpecker (Sapheopipo noguchii)
• Orange-bellied Parrot (Neophema chrysogaster)
• Philippine Eagle (Pithecophaga jefferyi)
• Po'ouli (Melamprosops phaeosoma)
• Puerto Rican Parrot (Amazona vittata)
• Raso Skylark (Alauda razae)
• Red-cockaded Woodpecker (Picoides borealis)
• Red-vented Cockatoo (Cacatua haematuropygia)
• Ridgway's Hawk (Buteo ridgwayi)
• São Tomé Grosbeak (Neospiza concolor)
• Siberian Crane (Grus leucogeranus)
• Slender-billed Curlew (Numenius tenuirostris)
• Socorro Mockingbird (Mimodes graysoni)
• Sociable Lapwing (Vanellus gregarius)
• Spix's Macaw (Cyanopsitta spixii)
• Sumatran Ground Cuckoo (Carpococcyx viridis)
• Takahe (Porphyrio hochstetteri)
• White-headed Duck (Oxyura leucocephala)
• White-shouldered Ibis (Pseudibis davisoni)
• Whooping Crane (Grus americana)
• Writhed-billed Hornbill (Aceros waldeni)
• Yellow-crested Cockatoo (Cacatua sulphurea)
• Zino's Petrel (Pterodroma madeira)

Endangered reptiles

• Blunt-nosed Leopard Lizard (Gambelia silus)
• Burmese Star Tortoise (Geochelone platynota)
• Californian Walking Bird (Augusto squamish)
• Coachella Valley Fringe-toed Lizard (Uma inornata)
• Cuban Crocodile (Crocodylus rhombifer)
• Flat Back Turtle (Natator depressa)
• Grand Skink (Oligosoma grande)
• Green Sea Turtle (Chelonia mydas)
• Hawksbill Turtle (Eretmochelys imbricata)
• Island Night Lizard (Xantusia riversiana)
• Kemp's Ridley (Lepidochelys kempii)
• Komodo Dragon (Varanus komodoensis)
• Leatherback Sea Turtle (Dermochelys coriacea)
• Loggerhead Sea Turtle (Caretta caretta)
• Mesoamerican River Turtle (Dermatemys mawii)
• Mona Ground Iguana (Cyclura stejnegeri)
• Monito Gecko (Sphaerodactylus micropithecus)
• Olive Ridley (Lepidochelys olivacea)
• Otago Skink (Oligosoma otagense)
• San Francisco garter snake (Thamnophis sirtalis tetrataenia)
• Smith's Dwarf Chameleon (Bradypodion taeniabronchum)
• St. Croix Ground Lizard (Ameiva polops)

Endangered amphibians

• Arroyo toad (Bufo californicus (=microscaphus))
• Australian Lace-lid (Nyctimystes dayi)
• Barton Springs Salamander (Eurycea sosorum)
• Baw Baw Frog (Philoria frosti)
• California Tiger Salamander (Ambystoma californiense)
• Desert Slender Salamander (Batrachoseps aridus)
• Fleischmann's Glass Frog (Hyalinobatrachium fleischmanni)
• Houston toad (Bufo houstonensis)
• Italian Spade-footed Toad (Pelobates fuscus insubricus)
• Mississippi Gopher Frog (Rana capito sevosa)
• Mountain Yellow-legged Frog (Rana muscosa)
• Palmate Newt (Triturus helvetica)
• Santa Cruz Long-toed Salamander (Ambystoma macrodactylum croceum)
• Shenandoah Salamander (Plethodon shenandoah)
• Sonoran Tiger Salamander (Ambystoma tigrinum stebbinsi)
• Spotted Tree Frog (Litoria Spenceri)
• Texas Blind Salamander (Eurycea rathbuni)
• Wallum Sedge Frog (Litoria olongburensis)
• Wyoming Toad ( Bufo baxteri (=hemiophrys))

Endangered fish

• Asian arowana (Scleropages formosus)
• Bonytail (Gila elegans)
• Chinese paddlefish (Psephurus gladius)
• Coelacanth (Coelacanthiformes)
• Colorado pikeminnow (Ptychocheilus lucius)
• Cui-ui (Chasmistes cujus)
• Dwarf Pygmy Goby (Pandaka pygmae)
• Gambusia eurystoma, native to Mexico, due to very limited habitat
• Humpback chub (Gila cypha)
• June sucker (Chasmistes liorus)
• Moapa dace (Moapa coriacea)
• Nassau grouper (Epinephelus striatus)
• Virgin River chub (Gila seminuda)

Endangered arthropods

• Alabama cave shrimp (Palaemonias alabamae)
• Delhi Sands flower-loving fly (Rhaphiomidas terminatus abdominalis), due to severely limited range of habitat and development
• Kentucky cave shrimp (Palaemonias ganteri)
• San Bruno elfin butterfly (Incisalia mossii bayensis), due to limited range of habitat and development encroachment
• Spruce-fir moss spider (Microhexura montivaga)
• Tasmanian giant freshwater crayfish (Astacopsis gouldi)
• Tooth cave spider (Neoleptoneta myopica)
• White-clawed crayfish (Austropotamobius pallipes)

Endangered mollusks

• Iowa Pleistocene Snail (Discus macclintocki)

Endangered plants

About 6% of the 300,000 identified species are endangered due to overcollection or destruction of habitat, among other causes. Pollinator decline is also a factor for some species. The following is a very small fraction of the endangered plants:

• African violet (Saintpaulia ionantha), due to forest clearance
• Baishanzu fir (Abies beshanzuensis) of southeast China, three trees known on an isolated mountain summit
• Baker's larkspur (Delphinium bakeri) of California, due to very limited habitat
• Chilean wine palm (Jubaea chilensis), due to land clearance
• Dawn Redwood (Metasequoia glyptostroboides), thought to be extinct until 1941, when a small stand was discovered in China
• Hickman's potentilla (Potentilla hickmanii), thought to be extinct until rediscovery in early 1990s.
• Kaka Beak (Clianthus puniceus) of New Zealand, due to introduced grazers and competing plants
• King of the Paphs Orchid (Paphiopedilum rothschildianum) of Asia, due to overcollection
• Louisiana Quillwort, (Isoetes louisianensis) of Louisiana, due to very limited habitat
• Madonna lily (Lilium candidum) of Europe, due to overcollection
• Muiri tree (Prunus africanus) of Kenya and neighboring countries, because of harvesting excessively and by improper methods
• Pinus squamata of southwest China, about 20 trees known
• Saguaro cactus (Carnegia gigantea) of North America, due to overcollection, slow maturing, and slow breeding
• Saharan Cypress (Cupressus dupreziana) of North Africa, due to small population and desertification
• Santa Cruz Tarweed (Holocarpa macradenia), of California, due to limited range of habitat and encroachment by man
• Tennessee coneflower (Echinacea tennesseensis) and Pyne's ground plum (Astragalus bibullatus) of the Nashville Basin of Tennessee, due to limited cedar glade habitat and its destruction by urbanization.
• Venus Flytrap (Dionaea muscipula) of North America, due to land clearance and overcollection.
• Wollemi pine (Wollemia nobilis) of Australia, also known as the 'Dinosaur Tree'. Wollemia fossils have been found in Australia, Antarctica and New Zealand. The plant was thought to be extinct until two trees were discovered in 1994. Research into the horticultural development of the Wollemi pine is being conducted at Mount Annan Botanic Garden. The plants are now available and commercially propagated.

Controversy

Some endangered species laws are controversial. Typical areas of controversy include: criteria for placing a species on the endangered species list, and criteria for removing a species from the list once its population has recovered; whether restrictions on land development constitute a "taking" of land by the government; the related question of whether private landowners should be compensated for the loss of use of their land; and obtaining reasonable exceptions to protection laws.

Being listed as an endangered species can backfire, since it could make a species more desirable for collectors and poachers [4]. However, this is usually a spurious argument by those favoring loose protection laws.

Another argument against listing species is the use of the "shoot, shovel, and shut up"[5] method of clearing endangered species from an area of land. Due to the fact that landowners currently may perceive a diminution in value for their land after finding an endangered animal on it, some owners have opted to silently kill and bury the animals, thus removing the problem from their land, but at the same time further reducing the population of an endangered species. It has also been noted that the effectivenes of the Endangered Species Act (ESA), which coined the term "endangered species", has been questioned. Only 15 species have been de-listed to date, and many of those species recovered from the stoppage of practices not related to the ESA, such as the use of DDT.

See also

• Biodiversity
• Conservation status
• Red and Blue-listed
• Convention on Biological Diversity
• Convention on the International Trade in Endangered Species of Wild Flora and Fauna (CITES)
• Extinct birds
• Endangered Species Act
• International Convention for the Regulation of Whaling
• List of endangered animal species
• List of extinct animals
• List of extinct and endangered animals of the British Isles
• Rare species
• Red Data Book of the Russian Federation
• Snail darter controversy
• Timeline of environmental events
• Ecological Economics

References

External links

• "The Sixth Extinction"
• U.S. Fish & Wildlife Service. Threatened and Endangered Species System (TESS).
• Endangered Species & Wetlands Report Independent print and online newsletter covering the ESA, wetlands and regulatory takings.
• Endangered species by continent
• Sundarbans Tiger Project Research and Conservation of tigers in the largest remaining mangrove forest in the world.
• Everything you wanted to know about endangered species — Provided by New Scientist.
• "Science counts species on brink". (Nov 17, 2004). BBC News.
• Endangered Native Carnivores in the Southern Rockies
• "Biodiversity and Conservation: A Hypertext Book by Peter J. Bryant
• Read Congressional Research Service (CRS) Reports regarding Endangered Species
• Endangered Species Information
• CBC Digital Archives – Endangered Species in Canada
• Bagheera website on endangered species
• "Who Will Save Our Animals? - Earth's Disappearing Wildlife", from Awake! magazine