Since about 1950, the populations of many species of amphibians (caecilians, frogs, toads, salamanders and newts) throughout the world have declined markedly; some species have become extinct. In many instances, these declines are attributable to adverse human influences acting locally, habitat degradation as a result of deforestation or draining of wetlands, urban encroachment, and pollution. Jump to: navigation, search 1950 was a common year starting on Sunday (link will take you to calendar). ... For other uses, see Amphibian (disambiguation). ... Families Rhinatrematidae Ichthyophiidae Uraeotyphlidae Scolecomorphidae Caeciliidae The Caecilians are an order (Gymnophiona or Apoda) of amphibians which resemble worms or snakes. ... Jump to: navigation, search Anton Ward is a frog (rebet) Genera Afrana Amietia Amnirana Amolops Aubria Batrachylodes Ceratobatrachus Chaparana Conraua Discodeles Euphlyctis Fejervarya Hildebrandtia Hoplobatrachus Huia Indirana Ingerana Lankanectes Lanzarana Limnonectes Meristogenys Micrixalus Minervarya Nannophrys Nanorana Nyctibatrachus Occidozyga Paa Palmatorappia Platymantis Pseudoamolops Pterorana Ptychadena Pyxicephalus Rana Sphaerotheca Staurois Strongylopus Tomopterna... Genera Ansonia Atelopus Bufo Capensibufo Crepidophryne Dendrophryniscus Didynamipus Frostius Laurentophryne Leptophryne Melanophryniscus Mertensophryne Nectophryne Nectophrynoides Nimbaphrynoides Oreophrynella Osornophryne Pedostibes Pelophryne Peltophryne Pseudobufo Rhamphophryne Werneria Wolterstorffina The true toads are amphibians in the Bufonidae family. ... Jump to: navigation, search Suborders Cryptobranchoidea Salamandroidea Sirenoidea Salamander is the common name applied to approximately 500 amphibian vertebrates with slender bodies, short legs, and long tails (order Caudata or Urodela). ... Jump to: navigation, search This article is about the animal called newt. ... Jump to: navigation, search In biology and ecology, extinction is the ceasing of existence of a species or group of taxons. ... Jump to: navigation, search Deforestation is the conversion of forested areas to non-forest. ... A subtropical wetland in Florida, USA, with an endangered American Crocodile. ... Jump to: navigation, search Pollution is the release of harmful environmental contaminants, or the substances so released. ...

In 1988, however, herpetologists from many parts of the world reported declines in amphibian populations in protected, apparently pristine habitats, such as national parks and nature reserves, where such local effects could not be implicated. This led to the suggestion that there may be one or more global factors that are adversely affecting amphibians. Possible candidates for such influences are climatic and atmospheric changes (for example, increased UV-B radiation), widespread pollution (e.g. acid rain), infectious disease and parasitic infestation. Jump to: navigation, search 1988 (MCMLXXXVIII) is a leap year starting on a Friday of the Gregorian calendar. ... Herpetology is the branch of zoology concerned with the study of reptiles and amphibians, including their classification, ecology, behavior, physiology, anatomy, and paleontology. ... Habitat (from the Latin for it inhabits) is the place where a particular species lives and grows. ... This article is about national parks. ... Jump to: navigation, search Layers of Atmosphere (NOAA) Earths atmosphere is the layer of gases surrounding the planet Earth and retained by the Earths gravity. ... Jump to: navigation, search Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ... Jump to: navigation, search Acid rain is defined as any type of precipitation with a pH of below 5. ... Jump to: navigation, search In medicine, infectious disease or communicable disease is disease caused by a biological agent (e. ... Jump to: navigation, search A parasite is an organism that lives in or on the living tissue of a host organism at the expense of that host. ...

Other factors include the introduction of non-indigenous predators and competitors. Purple flowers of the highly invasive Pattersons Curse infest the Warrumbungle National Park in New South Wales, Australia. ... Jump to: navigation, search This snapping turtle is trying to make a meal of a Canada goose, but the goose is too wary. ...

Pollution

Pollutants are causing frog deformities such as multiple limbs, stunted growth or misplaced eyes. Researcher and naturalist Gary Fellers has been tracking the deformation and decline of the frog population in Yosemite National Park in California. He attributed these occurrences directly to "pesticides wafting over the Sierra Nevada mountains from...farms in California's Central Valley". ("What's Killing the Frogs?” Newsweek May 13, 2003, pg 46). Pollutants are substances which directly or indirectly damage us and my kids daddy or the environment. ... Jump to: navigation, search Yosemite National Park (pronounced Yo-SEM-it-tee, IPA ) is a U.S. national park largely in Mariposa County, and Tuolumne County, California, United States. ... Jump to: navigation, search State nickname: The Golden State Other U.S. States Capital Sacramento Largest city Los Angeles Governor Arnold Schwarzenegger (R) Senators Dianne Feinstein (D) Barbara Boxer (D) Official language(s) English Area 410,000 km² (3rd)  - Land 404,298 km²  - Water 20,047 km² (4. ... Jump to: navigation, search An airplane spreading pesticide. ... Jump to: navigation, search The Sierra Nevada is a mountain range that is almost entirely in eastern California. ... Jump to: navigation, search The Newsweek logo Newsweek is a weekly news magazine published in New York City and distributed throughout the United States and internationally. ... Jump to: navigation, search 2003 (MMIII) is a common year starting on Wednesday of the Gregorian calendar. ...

Pollutants have varying effects on frogs. Some alter the central nervous system; others like atrazine cause a disruption in the production and secretion of hormones (UC Berkeley biologist Tyrone Hayes). Jump to: navigation, search A diagram showing the CNS. The central nervous system (CNS) represents the largest part of the nervous system. ... 2-chloro-4-(ethylamine)-6-(isopropylamine)-s-triazine, or Atrazine, is a s-triazine-ring herbicide that is used globally to stop pre and post emergence broadleaf and grassy weeds in major crops. ... The University of California, Berkeley (also known as Cal, UC Berkeley, UCB, or simply Berkeley) is a prestigious, public, coeducational university situated in the foothills of Berkeley, California to the east of San Francisco Bay, overlooking the Golden Gate and its bridge. ...

Recent evidence points to ozone as a possible contributing factor to the worldwide decline of amphibians (Dohm, M.R., et al. 2005. "Effects of ozone exposure on nonspecific phagocytic capacity of pulmonary macrophages from an amphibian, Bufo marinus." Environmental Toxicology and Chemistry 24 (January):205–210). Jump to: navigation, search Ozone (O3) is an allotrope of oxygen, the molecule consisting of three oxygen atoms instead of the more stable diatomic O2. ... Macrophages (Greek: big eaters) are cells found in tissues that are responsible for phagocytosis of pathogens, dead cells and cellular debris. ... Binomial name Bufo marinus Linnaeus, 1758 The Giant Neotropical Toad (Bufo marinus) is native to the Americas from southern Texas to northern Argentina. ...

A 2004 study by researcher Rick Relyea at the University of Pittsburgh found that populations of tadpoles declined greatly when exposed to the commonly used herbicide Roundup as well as the insecticides malathion and carbaryl. Another study in 2005 by the same researcher found that Roundup was also lethal to terrestrial frogs and toads. Specifically implicated is the surfactant POEA, a component of Roundup which is not itself a pesticide. Jump to: navigation, search The University of Pittsburgh is a state-related, doctoral/research university in Pittsburgh, Pennsylvania. ... Ten-day-old tadpoles A tadpole (also known as a pollywog) is a larval frog, toad, salamander, or newt. ... Jump to: navigation, search Image:Http://www. ... Roundup is the brand name of a family of herbicides produced by the American chemical manufacturer Monsanto. ... Jump to: navigation, search Insecticide application by crop spraying An insecticide is a pesticide whose purpose is to kill or to prevent the multiplication of insects. ... Malathion is a organophosphate parasympathomimetic which binds irreversibly to cholinesterase. ... Carbaryl is a chemical in the carbamate family used chiefly as an insecticide. ... Jump to: navigation, search Surfactants, also known as wetting agents, lower the surface tension of a liquid, allowing easier spreading, and the interfacial tension between two liquids. ...

Climate change

Large stands of ecosystem such as rainforests are being destroyed at a phenomenal rate decreasing available habitat. Also pollutants indirectly affect frogs by way of ozone depletion causing sun burn damage to the delicate moist skins of frogs, and further affecting their immune systems. Jump to: navigation, search In ecology, an ecosystem is a naturally occurring assemblage of organisms (plant, animal and other living organisms—also referred to as a biotic community or biocoenosis) living together with their environment (or biotope), functioning as a loose unit. ... Jump to: navigation, search Rainforest on Fatu-Hiva, Marquesas Islands A rainforest is a forested biome with high annual rainfall due to the Intertropical convergence zone. ... Jump to: navigation, search Image of the largest Antarctic ozone hole ever recorded in September 2000. ... Jump to: navigation, search The immune system is the system of specialised cells and organs that protect an organism from outside biological influences. ...

Parasites

Researcher Joseph Kiesecker focused research on a rural area of Pennsylvania where trematodes were present in ponds. His research indicated that frogs sheltered from the infiltration of parasites developed normally, while those that were exposed developed deformities. He also monitored the pesticide levels in the same ponds and found a magnification in the rate of parasitism in the polluted ponds suggesting that the presence of the pollutants reduces the frog’s immune response to parasitism. ("Pesticides Mess with Immunity" J. Pickrell Science News. July 13, 2003, p. 20) Jump to: navigation, search State nickname: The Keystone State Other U.S. States Capital Harrisburg Largest city Philadelphia Governor Ed Rendell (D) Senators Arlen Specter (R) Rick Santorum (R) Official languages None Area 119,283 km² (33rd)  - Land 116,074 km²  - Water 3,208 km² (2. ... Orders not necessarily a complete list Azygiida Echinostomida Opisthorchiida Plagiorchiida Strigeata Strigeatida Trematodes are also known as flukes. ... A pond is a body of water smaller than a lake. ... Jump to: navigation, search A parasite is an organism that lives in or on the living tissue of a host organism at the expense of that host. ...

Chytrid fungus

A parasitic fungus belonging to a chytrid family has been killing frogs in Australia, South America, Central and North America. The disease is called chytridiomycosis. The time from infection to death has been found to be 1–2 weeks in experimental tests. Jump to: navigation, search Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Yellow fungus Fungus growing on a tree in Borneo For the fictional character, see Fungus the Bogeyman. ... Orders Chytridiales Spizellomycetales Blastocladiales Monoblepharidales Neocallimasticales Chytridiomycota is a division of the Fungi kingdom and contains only one class, Chytridiomycetes. ... South America South America is a continent crossed by the equator, with most of its area in the Southern Hemisphere. ... Jump to: navigation, search Central America is the region of North America located between the southern border of Mexico and the northwest border of Colombia, in South America. ... Jump to: navigation, search World map showing North America A satellite composite image of North America North America is a continent in the northern hemisphere bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the south by the Caribbean Sea, and on... Chytridiomycosis is an infectious disease that affects amphibians, caused by the chytrid fungus. ...

In 1998, following large-scale frog deaths in Australia and Panama, research teams in both countries came up with identical results— a previously undescribed species of pathogenic fungus, Batrachochytrium dendrobatidis. Subsequent research has established that the fungus has been present in Australia since at least 1978. It now appears that some recent extinctions of Australian frog species were caused by this fungus. Jump to: navigation, search 1998(MCMXCVIII) is a common year starting on Thursday of the Gregorian calendar, and was designated the International Year of the Ocean. ... Jump to: navigation, search 1978 (MCMLXXVIII) was a common year starting on Sunday (the link is to a full 1978 calendar). ...

The fungus may have been exported from Africa, perhaps traveling with the African Clawed Frog, Xenopus laevis, which are sold in pet stores and used in laboratories around the world. // Etymology World map showing Africa (geographically) The name Africa came into Western use through the Romans, who used the name Africa terra — land of the Afri (plural, or Afer singular) — for the northern part of the continent, as the province of Africa with its capital Carthage, corresponding to modern-day... Binomial name Xenopus laevis Daudin, 1802 The African clawed frog (Xenopus laevis, also known as platanna) is a species of South African aquatic frog of the genus Xenopus. ... A pet store or pet shop is a store at which one can purchase supplies for pets and, often, the pets themselves. ...

Exotic species

Non-native predators and competitors are also affecting the viability of frogs in their habitats. The mountain yellow-legged frog which typically inhabits the Sierra Nevada lakes have seen a decline in numbers due to stocking of non-native fish (trout) for recreational fishing. The developing tadpoles and froglets fall prey to the fish in large numbers. This interference in the frog’s three year metamorphosis is causing a decline that is manifest throughout their ecosystem ("On the Rebound." Elizabeth Daerr, National Parks Magazine, January-February 2005, p. 49). Rainbow trout (Oncorhynchus mykiss) Trout is the common name given to a number of species of freshwater fishes belonging to the salmon family, Salmonidae. ... Jump to: navigation, search Fishing is the activity of hunting for fish. ... Metamorphosis has several meanings: Look up Metamorphosis in Wiktionary, the free dictionary For metamorphosis as it applies to animals (biology) see Metamorphosis (biology) In geology, metamorphosis refers to the changes undergone by metamorphic rock due to geological processes. ...

External links

• FrogWeb: Amphibian Declines & Malformations
• AmphibiaWeb
• Reply addressing Monsanto's reaction to findings in the Relyea study implicating Roundup and other pesticides.