Welke reptielen en amfibieën zijn in Nederland bedreigd?
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Cave splayfoot salamander (Chiropterotriton mosaueri) http://wdfw.wa.gov/ais/search.php?id=3&orderby=CommonName%20ASC ) Amphibians – Salamanders/Newts Species Image Species Name Common Name Ambystoma rosaceum Family Classification Ambystomatidae Prohibited Desmognathus ochrophaeus Allegheny Mountain Dusky salamander Plethodontidae Prohibited Echinotriton andersoni Anderson’s Salamander Salamandridae Prohibited Hynobius lichenatus Aomori salamander Hynobiidae Prohibited Aneides lugubris Arboreal salamander Plethodontidae Prohibited Triturus vittatus ophryticus Banded newt Salamandridae Prohibited Notophthalmus meridionalis Salamandridae Prohibited Black Spotted newt Desmognathus quadramaculatus Black-bellied salamander Plethodontidae Prohibited Desmognathus orestes Blue Ridge Dusky salamander Plethodontidae Prohibited Gyrinophilus porphyriticus Blue-Ridge Spring danielsi salamander Plethodontidae Prohibited Eurycea wilderae Blue-Ridge Two-lined salamander Plethodontidae Prohibited Ambystoma laterale Blue-spotted salamander Ambystomatidae Prohibited Triturus boscai Bosca’s newt Salamandridae Prohibited Hynobius boulengeri Boulenger’s Oriental salamander Hynobiidae Prohibited Dicamptodon ensatus California Giant salamander Dicamptodontidae Prohibited Batrachoseps attenuatus California Slender salamander Plethodontidae Prohibited Ambystoma californiense California Tiger salamander Ambystomatidae Prohibited Triturus montandoni Carpathian newt Salamandridae Prohibited Eurycea lucifuga Cave salamander Plethodontidae Prohibited Andrias davidianus Chinese Giant salamander Cryptobranchidae Prohibited Hynobius chinensis Chinese salamander Hynobiidae Prohibited Paramesotriton chinensis Chinese Warty newt Salamandridae Prohibited Hynobius nebulosus Clouded salamander Hynobiidae Prohibited Aneides ferreus Clouded salamander Plethodontidae Prohibited Triturus dobrogicus Danube Crested newt Salamandridae Prohibited Plethodon elongatus Del Norte salamander Plethodontidae Prohibited Batrachoseps aridus Desert Slender salamander Plethodontidae Prohibited Hynobius dunni Dunn’s Oriental salamander Hynobiidae Prohibited Plethodon dunni Dunn’s salamander Plethodontidae Prohibited Eurycea quadridigitata Dwarf salamander Plethodontidae Prohibited Salamandrella keyserlingii Dybowski’s salamander Hynobiidae Prohibited Siren intermedia intermedia Eastern Lesser siren Sirenidae Prohibited Pseudotriton montanus montanus Eastern Mud salamander Plethodontidae Prohibited Notophthalmus viridescens Eastern newt Salamandridae Prohibited Plethodon cinereus Eastern Red-backed salamander Plethodontidae Prohibited Hemidactylium scutatum Four-toed salamander Plethodontidae Prohibited Hydromantes ambrosii French Cave salamander Plethodontidae Prohibited Hydromantes genei Gene’s Cave salamander Plethodontidae Prohibited Chioglossa lusitanica Gold Striped salamander Salamandridae Prohibited Batrachuperus gorganensis Gorgan salamander Hynobiidae Prohibited Triturus cristatus Great Crested newt Salamandridae Prohibited Siren lacertina Greater siren Sirenidae Prohibited Aneides aeneus Green salamander Plethodontidae Prohibited Necturus beyeri Gulf Coast Waterdog Proteidae Prohibited Batrachoseps diabolicus Hell Hollow Slender salamander Plethodontidae Prohibited Cryptobranchus alleganiensis Hellbender Cryptobranchidae Prohibited Paramesotriton hongkongensis Hong Kong Warty newt Salamandridae Prohibited Hynobius kimurae Hynobiidae Hynobiidae Prohibited Dicamptodon aterrimus Idaho giant salamander Dicamptodontidae Prohibited Desmognathus imitator Imitator salamander Plethodontidae Prohibited Hydromantes imperialis Imperial Cave salamander Plethodontidae Prohibited Batrachoseps campi Inyo Mountains salamander Plethodontidae Prohibited Hydromantes italicus Italian Cave salamander Plethodontidae Prohibited Triturus carnifex Italian Crested newt Salamandridae Prohibited Triturus italicus Italian newt Salamandridae Prohibited Onychodactylus japonicus Japanese Clawed salamander Hynobiidae Prohibited Plethodon jordani Jordan’s salamander Plethodontidae Prohibited Neurergus microspilotus Kurdistan newt Salamandridae Prohibited Neurergus crocatus Lake Urmia newt Salamandridae Prohibited Plethodon larselli Larch Mountain salamander Plethodontidae Prohibited Hydromantes brunus Limestone salamander Plethodontidae Prohibited Onychodactylus fischeri Long-Tailed Clawed salamander Hynobiidae Prohibited Neurergus kaiseri Luristan newt Salamandridae Prohibited Triturus marmoratus marmoratus Marbeled newt Salamandridae Prohibited Ambystoma opacum Marbled salamander Ambystomatidae Prohibited Plethodon mississippi Mississippi Slimy salamander Plethodontidae Prohibited Hydromantes platycephalus Mount Lyell salamander Plethodontidae Prohibited Hynobius retardatus Noboribetsu salamander Hynobiidae Prohibited Hynobius leechii Northeastern China Hynobiid salamander Hynobiidae Prohibited Desmognathus fuscus fuscus Northern Dusky salamander Plethodontidae Prohibited Pseudobranchus striatus striatus Northern Dwarf siren Sirenidae Prohibited Pseudotriton ruber ruber Northern Red salamander Plethodontidae Prohibited Plethodon glutinosus Northern Slimy salamander Plethodontidae Prohibited Eurycea bislineata Northern Two-lined salamander Plethodontidae Prohibited Plethodon dorsalis Northern Zigzag salamander Plethodontidae Prohibited Desmognathus ocoee Ocoee salamander Plethodontidae Prohibited Hynobius okiensis Oki salamander Hynobiidae Prohibited Proteus anguinus Olm Proteidae Prohibited Batrachuperus mustersi Paghman Mountain salamander Hynobiidae Prohibited Triturus helveticus helveticus Palmate newt Salamandridae Prohibited Batrachuperus persicus Persia Mountain salamander Hynobiidae Prohibited Plethodon petraeus Pigeon Mountain salamander Plethodontidae Prohibited Desmognathus wrighti Pygmy salamander Plethodontidae Prohibited Euproctus asper Pyrenean Brook salamander Salamandridae Prohibited Taricha rivularis Red-bellied newt Salamandridae Prohibited Batrachoseps gabrieli San Gabriel Mountains Slender salamander Plethodontidae Prohibited Speleomantes imperialis Scented Cave salamander Plethodontidae Prohibited Desmognathus monticola Seal salamander Plethodontidae Prohibited Pachyhynobius shangchengensis Shangcheng Stout salamander Hynobiidae Prohibited Hydromantes shastae Shasta salamander Plethodontidae Prohibited Pseudohynobius shuichengensis Shiucheng salamander Hynobiidae Prohibited Ranodon sibiricus Siberian salamander Hynobiidae Prohibited Taricha torosa Sierra newt Salamandridae Prohibited Triturus vulgaris lantzi Smooth newt Salamandridae Prohibited Triturus karelinii Salamandridae Prohibited Plethodontidae Prohibited Plethodon richmondi Southern Ravine salamander Plethodontidae Prohibited Eurycea cirrigera Southern Two-lined salamander Plethodontidae Prohibited Aneides flavipunctatus Speckled Black salamander Plethodontidae Prohibited Salamandrina terdigitata Spectacled salamander Salamandridae Prohibited Paramesotriton caudopunctatus Spot-Tailed Warty newt Salamandridae Prohibited Pachytriton labiatus Spotless Paddle Tail newt Salamandridae Prohibited Pachytriton brevipes Spotted Paddle Tail newt Salamandridae Prohibited Neurergus strauchii strauchii Strauch’s Spotted newt Salamandridae Prohibited Salamandridae Prohibited Hydromantes supramontis Supramont Cave salamander Plethodontidae Prohibited Batrachuperus taibaiensis Taibai Stream salamander Prohibited Southern Crested newt Desmognathus auriculatus Southern Dusky salamander Notophthalmus perstriatus Striped newt Hynobiidae Paramesotriton deloustali Tam Dao Warty newt Salamandridae Prohibited Eurycea guttolineata Three-lined salamander Plethodontidae Prohibited Amphiuma tridactylum Three-toed Amphiuma Amphiumidae Prohibited Ambystoma tigrinum Tiger salamander Ambystomatidae Prohibited Pseudohynobius tsinpaensis Tsinpa salamander Hynobiidae Prohibited Plethodon hoffmani Valley And Ridge salamander Plethodontidae Prohibited Plethodon vandykei Van Dyke’s salamander Plethodontidae Prohibited Aneides vagrans Wandering salamander Plethodontidae Prohibited Plethodon wehrlei Wehrle’s salamander Plethodontidae Prohibited Plethodon welleri Weller’s salamander Plethodontidae Prohibited Batrachuperus pinchonii Western Chinese Mountain salamander Hynobiidae Prohibited Plethodon vehiculum Western Red-backed salamander Plethodontidae Prohibited Plethodon cylindraceus White-spotted Slimy salamander Plethodontidae Prohibited Liua shihi Wushan salamander Hynobiidae Prohibited Pseudohynobius flavomaculatus Yellow-spotted salamander Hynobiidae Prohibited Plethodon yonahlossee Yonahlossee salamander Plethodontidae Prohibited Ook hier kan je op de foto’s klikken Andrias Naish2.jpg While the name currently in use for Asian giant salamanders (and their fossil relatives) is Andrias, the equally old Megalobatrachus has also been used a lot. Both were created by the same author (J. J. v. Tschudi), in the same year (1837), in the same published work, but Andrias was traditionally restricted to fossils and Megalobatrachus was traditionally restricted to the living species. Westphal (1958) argued that both should be synonymised, with Andrias taking priority. Some authors have regarded Andrias giant salamanders and hellbenders as part of the same genus (in part because they’ve regarded Andrias as paraphyletic with respect to Cryptobranchus), and have therefore used the name Cryptobranchus Leuckart, 1821 for the whole lot (Naylor 1981). More recent work has found both Andrias and Cryptobranchus to be monophyletic; fossils indicate that they had diverged by the Paleocene. reconstruction of a Californian giant salamander Rodgers suggested that, if the stories were true, they might be based on sightings of large Dicamptodon (Pacific giant salamanders), though individuals larger than just 30 cm would be exceptional [the above reconstruction of a Californian giant salamander - look at the scale! - is by Harry Trumbore and comes from Coleman & Huyghe (2003). Yeah, too many fingers]. A. japonicus skull A. japonicus An entirely different ‘mystery giant salamander’ has been reported from Hong Kong where one was captured in the Botanical Gardens, Mid Levels, Hong Kong Island in 1922. This specimen was taken to London Zoo where it lived for many years; photos of it can be seen in zoo guide books published during the 1930s. In 1924, Edward G. Boulenger described it as representing the distinct species Megalobatrachus sligoi: it was supposedly distinct from the others on account of its smoother skin and flatter head (Boulenger 1924). It’s been stated that additional specimens were later captured, though the details on these are extremely hazy. It’s generally accepted today that Sligo’s salamander is synonymous with A. davidianus, though I’ve been unable to discover whether the individual(s) concerned were possible natives or the result of introduction (let me know if you have more information); the species is missing from field guides to the Hong Kong herpetofauna (e.g., Karsen et al. 1986) (thanks to Jon Downes, CFZ, for pers. comms.) [A. japonicus skeleton is shown } Naish9.jpg 1887 illustration of a Japanese giant salamander from wikipedia]. Scheuchzer's zondvloedmens fossil Andrias salamanders, the most famous of them all is A. scheuchzeri from the Upper Miocene of Oeningen, Germany [shown here, by Haplochromis, from wikipedia]. The holotype skeleton discovered in or prior to 1725 - was first assumed to be that of a man killed in the biblical flood. Naish6.jpg Zdeněk Burian's reconstruction of A. scheuchzeri is shown here. As always, it looks great, but it's not accurate: Andrias salamanders are strictly aquatic]. Naish8.jpg During the breeding season, Andrias salamanders species build long, horizontal mud burrows (as much as 1.5 m long) below the water line. The males that do this - dubbed ‘den-masters’ by Kawamichi & Ueda (1998) - are the longest and heaviest individuals in their habitats. They lay in wait in the burrows, emerging to attack other males that come into the territory. Some males quickly flee, but others stay and fight, and many individuals (as many as 17, perhaps more) may congregate outside the burrow and aim to get inside and mate with visiting females. I knocked up the terrible cartoon below to illustrate a few salient features of Andrias breeding behaviour. Table Mountain ghost frog (Heleophryne rosei). The family to which the Table Mountain ghost frog belongs represents the most ancient members of the Neobatrachia suborder (the modern frogs and toads) having diverged from their closest ancestors over 160 million years ago. Found only on Table Mountain in South Africa this species occupies an area that is just 7-8 km sq and lives in forest and fynbos heathland using streams to breed in. Morphological features such as a squat, compressed body and highly webbed feet that make it a strong swimmer means this species well adapted to the rocky mountain streams in which it lives. Tadpoles have sucking mouthparts that allow them to hold onto rock faces when feeding and climbing. This rare and elusive species is listed as Critically Endangered on the IUCN Red List and faces a number of threats such as the spread of non-native vegetation that can block streams, frequent fires, heavy ecotourism, the construction of dams along waterways and the fungal disease chytridiomycosis. Currently, the whole of the range in which this species is found is protected by the Table Mountain National Park but maintenance of its remaining habitat is essential. This may be possible by collaborating with the local forestry services to manage a buffer zone of native plants around the streams that this species uses. It is also essential that policy continues to mandate that dams permit a continuous flow of downstream water to ensure streams are not lost. D_nigriventer1.jpg Hula painted frog (Discoglossus nigriventer): an ancient frog that has not been seen since 1955. Its habitat in the Hula wetlands was drained in the 1950s in an attempt to eradicate malaria and develop agriculture land uses Rheobatrachus-silus04.jpg Southern gastric brooding frog (Rheobatrachus silus): females of this extraordinary frog cared for their developing young within their own stomachs by shutting down all digestive processes and fasting for up to 7 weeks. This species has not been seen since 1979. Leiopelma-hochstetteri.jpg Hochstetter’s frog (L. hochstetteri). Leiopelma-hochstetteri--(Nu.jpg Archey’s frog (Leiopelma archeyi) The Purple frog (Nasikabatrachus sahyadrensis) La Hotte Glanded Frog Ventriloqual Frog Mozart's Frog Macaya Burrowing Frog Macaya Burrowing Frog Macaya Burrowing Frog Macaya Burrowing Frog Macaya Breast-Spot Frog Macaya Breast-Spot Frog Macaya Breast-Spot Frog Hispaniola Crowned Frog Haitian Cloud Forest Add Facebox < prev #22 of 23 next > marmer-salamander.JPG foto koen Vermimmen Juveniel mannetje Slideshow Esclottes France 2006 Mole salamanders.JPG http://evodisku.multiply.com/journal/item/321/LateraleLGT_Horizontale_genoverdrachtHGT http://www.vernalpool.org/inf_mol.htm Herpetologists have long debated about the taxonomic status of blue-spotted and jefferson salamanders. Both are now recognized as their own species, although it is thought that they evolved into two species when populations of a common ancestral species were separated by glaciers during the last Ice Age. After the glaciers melted, the two species came into contact again and interbred, producing hybrids with three or four sets of chromosomes ("triploid" or "tetraploid", as opposed to organisms with two pairs of chromosomes referred to as "diploid"). These hybrids are difficult to tell apart from jefferson and blue spotted salamanders, without performing genetic analyses. Blue spotted salamanders are generally blue-black and sprinkled with small blue spots, while Jefferson salamanders tend to be more brown with fewer blue or gray spots on the body. In contrast, both the yellow spotted and marbled salamanders are easy to identify. Spotted salamanders are distinguished by two dorsal rows of big yellow spots. Marbled salamanders have bands of white, grey, or silver on their backs. Spring migrations of mole salamanders are a fascinating and awe-inspiring event, for both children and adults alike. These migrations, however, can put salamanders in danger. During migration, salamanders may have to cross roads which have been made through wetlands or forests and can be run over by unsuspecting motorists. In addition, the small, ephemeral pools in which they breed might be regarded as "insignificant puddles" and filled in by developers or homeowners. You can help mole salamanders by being alert for migrations across roads when driving on rainy nights in early spring. Massachusetts also has a certification program run by the Natural Heritage and Endangered Species Program, which alerts the state to the existence of a vernal pool and provides information which may be used by the state to prevent irresponsible development in and around ponds which mole salamanders use for breeding. References Degraaf, R. M., and D. D. Rudis. 1986. New England wildlife: habitat, natural history, and distribution. General Technical Report NE-108, Northeastern Forest Experiment Station. 491 pp. Hunter, M. J., J. Albright, and J. Arbuckle (editors). 1992. The amphibians and reptiles of Maine. Maine Agricultural Experiment Station Bulletin 838. 188 pp. Kenney, L. P. 1995. Wicked big puddles: a guide to the study and certification of vernal pool. Vernal Pool Association. 58 pp. plus appendices. Pfingsten, R. A., and F. L. Downs (editors). 1989. Salamanders of Ohio. Ohio Biological Survey Bulletin New Series Vol. 7 No. 2. 315 pp. Tyning, T. F. 1990. Amphibians and reptiles. Little, Brown, and Company, Boston. 400 pp. *Spotted salamander *Blue-spotted salamander *Jefferson salamander *Marbled salamander (click on thumbnails) Pandemie van de chytridiomycosis Zorgwekkend was de laatste jaren al de raadselachtige massale bijensterfte. Ook vleermuizen geven met kolonies tegelijk de geest; onder de nachtfladderaars houdt een schimmel genadeloos huis. Nu kan men biologisch-puristisch betogen dat het uitsterven van dieren sinds de oerknal de natuurlijkste zaak van de wereld is. Triceratops, iguanodon, protarchaeopteryx, sabeltandtijger – allemaal gingen ze evolutionair af door de zijdeur. Met het significante verschil dat de mens daarmee niets van doen had. Vrijwel iedere ziekte en plaag waarmee we in het derde millennium worden geconfronteerd is echter in sterke mate een uitvloeisel van hoe de mens met milieu en natuur omgaat. Broeikasverhaal, ontbossing, chemisch afval, antibiotica in veevoeders, monocultuur, industrële overbevissing, plasticberg, bio-industrie – het zijn slechts enkele bewijsstukken voor de these dat de homo sapiens de grootste gesel is van Planeet Aarde. Dat de chytriden zich zo voortvarend verspreiden onder amfibieën in vrijwel alle delen van de wereld, heeft wellicht te maken met het feit dat de mens zich tegenwoordig zo eenvoudig naar alle uithoeken verplaatst. Kwetsbare dieren en organismen, zelfs die levend in een afgelegen en bedrieglijk veilige biotoop, hebben geen verweer tegen de geluidloos geïmporteerde massamoordenaars op microgrootte. Het is te hopen dat de amfibieënschimmel tot staan wordt gebracht. Zonder dat gerustellend gekwaak wordt die vijver nooit meer hetzelfde. http://en.wikipedia.org/wiki/Chytridiomycosis http://tropicalis.berkeley.edu/home/husbandry/disease.html http://www.fourwinds10.com/siterun_data/environment/plants_and_animals/news.php?q=1218941303 Amphibian chytridiomycosis Amphibian chytridiomycosis is the infection of amphibian skin cells by the microscopic fungus (Batrachochytrium dendrobatidis). Batrachochytrium dendrobatidis. Two jar-shaped zoosporangium, or thalli (A), and zoospores inside are clearly visible. The discharge tubule is also visible where the flagellated zoospores are released from the thallus (B). Photograph courtesy of A. Pessier, University of Illinois Zoological Pathology Program, Loyola University Medical Center. http://www.fourwinds10.com/siterun_data/environment/plants_and_animals/news.php?q=1218941303 “Amphibians are an ancient organism, which has survived past extinctions, and is telling us that something is wrong right now (on Earth). The question is whether we humans will listen before it's too late.” - Vance Vredenburg, Ph.D., Biology, San Francisco State Already steeply in decline, the critically endangered yellow-legged frogs died at Sixty Lake Basin in California in August 2006. Their killer is the Chytrid fungus (Chytridiomycosis) which has devastated amphibian populations from California to Panama to Brazil to Australia over the past decade. Image courtesy David Wake, Ph.D. and Vance Vredenburg, Ph.D., co-authors of August 12, 2008, report in the Proceedings of the National Academy of Sciences. August 15, 2008 Berkeley, California - Frogs, toads, salamanders, newts and caecilians – all amphibians – are among the oldest creatures on Earth. Amphibians have survived the last four of five mass extinctions on this planet. [ Editor's Note: From the August 12, 2008, Proceedings of the National Academy of Sciences, "Are We in the Midst of the Sixth Mass Extinction? A view from the world of amphibians. Authors: David B. Wake, Director of Herpetology, Museum of Vertebrate Zoology, University of California, Berkeley, California; and Vance T. Vredenburg, Prof. of Biology, San Francisco State University, San Francisco, California. See websites below. “Five Mass Extinctions It is generally thought that there have been five great mass extinctions during the history of life on this planet. In each of the five events, there was a profound loss of biodiversity during a relatively short period. 1) The oldest mass extinction occurred at the Ordovician–Silurian boundary (≈ 439 Million Years Ago). Approximately 25% of the families and nearly 60% of the genera of marine organisms were lost. Contributing factors were great fluctuations in sea level, which resulted from extensive glaciations, followed by a period of great global warming. Terrestrial vertebrates had not yet evolved. 2) The next great extinction was in the Late Devonian (≈364 Mya), when 22% of marine families and 57% of marine genera, including nearly all jawless fishes, disappeared. Global cooling after bolide impacts may have been responsible because warm water taxa were most strongly affected. Amphibians, the first terrestrial vertebrates, evolved in the Late Devonian, and they survived this extinction event. 3) The Permian–Triassic extinction (≈ 251 Mya) was by far the worst of the five mass extinctions; 95% of all species (marine as well as terrestrial) were lost, including 53% of marine families, 84% of marine genera, and 70% of land plants, insects, and vertebrates. Causes are debated, but the leading candidate is flood volcanism emanating from the Siberian Traps, which led to profound climate change. Volcanism may have been initiated by a bolide impact, which led to loss of oxygen in the sea. The atmosphere at that time was severely hypoxic, which likely acted synergistically with other factors. Most terrestrial vertebrates perished, but among the few that survived were early representatives of the three orders of amphibians that survive to this day. 4) The End Triassic extinction (≈199–214 Mya) was associated with the opening of the Atlantic Ocean by sea floor spreading related to massive lava floods that caused significant global warming. Marine organisms were most strongly affected (22% of marine families and 53% of marine genera were lost), but terrestrial organisms also experienced much extinction. Again, representatives of the three living orders of amphibians survived. 5) The most recent mass extinction was at the Cretaceous–Tertiary boundary (≈65 Mya); 16% of families, 47% of genera of marine organisms, and 18% of vertebrate families were lost. Most notable was the disappearance of nonavian dinosaurs. Causes continue to be debated. Leading candidates include diverse climatic changes (e.g., temperature increases in deep seas) resulting from volcanic floods in India (Deccan Traps) and consequences of a giant asteroid impact in the Gulf of Mexico. Not only did all three orders of amphibians again escape extinction, but many, if not all, families and even a number of extant amphibian genera survived. 6) A Sixth Extinction? The possibility that a sixth mass extinction spasm is upon us has received much attention. Substantial evidence suggests that an extinction event is underway.” ] Since the 1990s, amphibians have been dying out around the world in increasing numbers. In fact, 2008 was declared the Year of the Frog by the Amphibian Ark organization dedicated to saving amphibians. One of the culprits behind the alarming amphibian die-off is called the chytrid (KYE-trid) fungus. Surprisingly, it was not identified by scientists until 1998, only ten years ago. By 2008, after ten years of intense study, no one yet understands how the chytrid fungus is killing frogs, toads, salamanders and other amphibians. Another mystery is how does the fungus spread so fast? Scientists have documented year-by-year waves of amphibian die-offs moving over vast geographic distances. Once the chytrid fungus is in a new region, most of the amphibians are killed in only a year’s time. In the August 12, 2008, Proceedings of the National Academy of Sciences, a zoologist and biologist presented data about the question: Is Earth now in a 6th mass extinction that could see thousands of species on land, in water and air die off forever, as happened 65 million years ago when it is hypothesized that an asteroid slammed into the Gulf of Mexico and wiped out the dinosaurs along with 70% of all earth life in the fifth mass extinction event? Scientists are concerned that a growing data base of die-offs means the answer is yes and that the increasing decline of amphibians is the alarm bell. This time, human civilization is equivalent to the destructive asteroid. Our human territories continue to expand, which shrinks the natural wild habitats. Human industries are warming the planet, forcing animals and plants to move with temperature changes into new territories. Changing ecosystems provoke insects, bacteria, viruses, algae and fungi to also change their tactics in living off other earth creatures. Further, our massive commercial food industries are filling soils and plants with a wide range of pesticides that scientists know can be especially hard on amphibians that breathe through their skin. One of the NAS Proceedings authors is Prof. Vance Vredenburg, Asst. Professor of Biology at San Francisco State University. He says that because amphibians are such ancient earth animals that survived previous mass extinctions, we humans should all be alarmed that “something is wrong in our world. We humans might be doing OK right now, but the amphibians are doing poorly.” The question is - will humans pay serious attention to the amphibian warning before it’s too late for all life? Prof. Vredenburg’s co-author is David Wake, Curator of Herpetology in the Museum of Vertebrate Zoology at the University of California-Berkeley. This week I talked with him about data from the 2004 first global assessment of all species in the world. That study concluded there are about 6,000 species of amphibians. Of those, one-third were on the brink of extinction and another 40% are threatened with extinction. And for reasons unknown, the chytrid fungus is the leading killer of amphibians. Interview: David Wake, Ph.D., Curator of Herpetology, Museum of Vertebrate Zoology, University of California-Berkeley: “By 2005 to 2006, the results were in and the chytrid fungus has had a profound impact on populations of amphibians, particularly in Central America and the mountains of California and in the tropical mountains of Australia. HOW DOES THE CHYTRID FUNGUS KILL? Left: Chytrid fungus infection shows in the pink underbelly of green tree frog. Right: Great barred frog has a severe Chytrid fungus infection that is causing its skin to peel off. Images by Australia National Parks and Wildlife Service. We don’t know exactly. That’s the question I always ask in scientific meetings. What is the immediate cause of death? There are hypotheses. The chytrid fungus is a rather simple organism – genetically complex – but simple in structure that invades the superficial surface of the skin of amphibians. The chytrid fungus lives on keratin. When we feel our skin, that’s what we are feeling. [Keratins are the main constituent of structures that grow from the skin.] Keratin is the outermost surface. So, the chytrid fungus eats this keratin stuff that was not considered nutritious for organisms, but the chytrid fungus favors keratin. Above: Chytrid fungus cells about to release more spores. Below: Electron micrograph of chytrid fungus on frog skin. Photomicrographs by Lee Berger, Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO). When an amphibian gets a massive infection of the chytrid fungus, it probably interferes with the amphibian's respiration because even those creatures with excellent lungs actually have most of the gaseous exchange across their moist skins. So, they suffocate in their own skin. I can’t prove that, but it’s a general consensus of researchers. BECAUSE AMPHIBIANS BREATHE THROUGH THEIR SKIN. They do. They get 90%, or in some cases 100%, of their respiration through their skin. There are many frogs and salamanders that are even lungless. So, the lungs are not necessary at all for amphibian respiration. Amphibians depend upon their highly vascularized, moist skins for respiration. Chytrid Fungus “Jumps Boundaries and Causes Havoc” PROF. VREDENBURG, YOUR COLLEAGUE ON THIS RESEARCH, WAS QUOTED IN SCIENCE DAILY AS SAYING, ‘IT’S IMPORTANT FOR PEOPLE TO UNDERSTAND WHAT’S INFECTING AND KILLING THESE FROGS. THIS DISEASE IS A REMARKABLE EXAMPLE OF A PATHOGEN JUMPING BOUNDARIES AND CAUSING HAVOC. COULD YOU EXPLAIN THAT? Yes, because we don’t really know how this pathogen moves around. First, we don’t know where it came from. It just emerged. It’s a phylogenetically very isolated taxon. It has no close relative, so we can’t look at any close relatives and ask: how do they live? What do they live on? The chytrid fungus is very isolated. But it has been traced back to the 1940s in the clawed frog of Africa. The leading hypothesis about its spread is that people started spreading the clawed frog around. [ Editor’s Note: Wikipedia - Phylogenetics means relative to birth and is the study of evolutionary relatedness among various groups of organisms. Taxonomy, the classification of organisms according to similarity, has been richly informed by phylogenetics, but remains methodologically and logically distinct. A taxon (plural taxa), or taxonomic unit, is a name designating an organism or a group of organisms.] Clawed Frog - Origin of Chytrid Fungus? African clawed frog (Xenopus laevis), also known as platanna. Image © by John Elkington. [ Editor’s Note: The genus Xenopus is aquatic and the only frog with clawed toes. The African clawed frog has a flat body with a relatively small head. Its skin is smooth, with dorsal surfaces usually colored in mottled hues of olive-brown or gray with darker marks and ventral surfaces a creamy white color. This frog has no tongue, no teeth, no eyelids, and no external eardrums. Its forelimbs have four unwebbed fingers and its hind limbs have five long, webbed toes with dark claws on the three outer toes. The genus is found throughout much of Europe, North America, South America and Africa. When African clawed frogs are imported into non-native countries, they have the capacity to wreck entire ecosystems by eating native wildlife such as fish and turtles that have no natural defense against these creatures. In 2007, these frogs invaded a pond in San Francisco, where much debate exists on how to terminate these creatures and keep them from spreading. It is unknown if these frogs entered the San Francisco ecosystem through intentional release or escape into the wild. Because these frogs are immune to the fungi Batrachochytrium dendrobatidis (a chytridomycota) and B. dendrobatidis has been traced back to the habitat of Xenopus laevis in Africa, many scholars believe it is the source of the worldwide amphibian die-off caused by the chytrid fungus. ] David Wake, Ph.D.: “I remember this well when clawed frogs were the main organisms used for human pregnancy tests. What happened was that you would take urine from a possibly pregnant woman. You would inject the urine into a clawed frog and if the frog laid eggs, the woman was pregnant. That was the way it was done! So, these frogs, which are aquatic, lived in aquariums in doctor’s offices all around the world and the frogs were moved around. Then, these frogs were heavily used as model organisms. They became THE amphibian for the model organism. That meant the clawed frog was heavily used in laboratories. People released them into streams and ponds when they were done with them. That should not have happened, but now there are established populations of clawed frogs in southern California, for example. So we know this was happening. But now what we would like to know is that once the chytrid fungus was in the clawed frogs, somehow the fungus jumped the boundaries. They jumped from one species into another. Now, the chytrid fungus seems to be able to move quite long distances and we would really like to know how they do that. Now, why is the chytrid fungus having this profound impact on amphibians? Some people think it’s linked to global climate change. Other people question that. But, it’s undeniable that there is this high correlation between the arrival of the chytrid fungus in the population and the collapse of that amphibian population within a year. WITHIN A YEAR? Within a year. WHAT WOULD THERE BE ABOUT THE AVERAGE GLOBAL TEMPERATURE OF THE EARTH INCREASING THAT WOULD SUDDENLY MAKE A CHYTRID FUNGUS BE ABLE TO KILL SO MANY AMPHIBIANS? The chytrid fungus operates in mountain environments. There are people who have presented the argument that the cloud line is rising. What that means is in these mountain areas, you have clouds at night. That means it is warmer at night than it used to be in the past and it’s cooler by day. This narrower range of temperatures, it is hypothesized, favors the growth of the chytrid fungus. CAN YOU PROJECT INTO THE FUTURE ABOUT WHAT THIS DIE-OFF MEANS FOR THE FUTURE POPULATION OF AMPHIBIANS? Yes, I can in fact, because this has been done by Karen Lips at the Univ. of Southern Illinois. [ See websites below.] She has been working from Costa Rico into Panama. In 1990, I was in the field with her when she was choosing her study site. By 1994, the frogs were beginning to disappear from her study site. She could not figure out why. Karen Lips and Australian scientists almost simultaneously discovered that the chytrid fungus was hitting both Australian frogs and Costa Rican frogs. Really weird! A Panamanian Golden Frog killed by chytrid fungus in central Panama. Source: Saveafrog.org. So, Karen shifted her attention to an area further south. A year later in 1995, that area was hit by chytrid fungus and devastated. Then Karen Lips made a prediction. She hypothesized that there was a wave-affect of this chytrid fungus and it was moving south. She started taking extreme precautions herself by disinfecting her boots before she went into her study site. She laid out study areas further to the south and the east and she predicted the pathogen would arrive there and have a devastating effect. And she was right, absolutely right. Chytrid Fungus Devastated Amphibians in Panama's El Cope National Park El Cope National Park, Panama. Finally, she predicted that the pathogen would reach El Cope National Park in Panama. It did and wiped out the population of amphibians there. At that point, the Amphibian Ark was established. [ See websites below.] Amphibian Ark is an organization associated with the American Zoological Park, sponsored by them, and headed by some highly competent herpetologists who know amphibians extremely well. They went through the extraordinary activity of removing living frogs from the field at the next place down from the devastated Panama site. The scientists moved those still-uninfected amphibians into captive breeding, taking them out of their natural environment and moving them into captive breeding to protect them. This is really an extreme measure because you have to assume you’re going to be successful – and thankfully, I think they are being successful in getting the amphibians to thrive in captivity. But you have to hope that something is going to change in the environment so that it will be safe for them to be returned to their natural home at some point. Possibly, if the environment is free of frogs, there will be nothing for the chytrid fungus to live on and it will die out. That’s the hope, as I understand it. How Does the Chytrid Fungus Spread So Rapidly? HOW DO YOU THINK THE CHYTRID FUNGUS SPREADS SO RAPIDLY? That’s THE question. We do not know how it’s making it. Chytrid seems to go too fast to be explained by adjacency from one frog to the next to the next. Some people think maybe birds are transmitting the chytrid fungus on their legs. But, as far as I know, it’s never been shown that the fungus has infected a bird. The chytrid fungus zoospores are really quite fragile. They dry out easily and they die easily. So, transmission is really the big question in my mind. This was directed at herpetologists themselves – maybe they were transmitting it in mud on their boots. So, this is why all herpetologists going into the field now disinfect their boots. Chytridiomycosis. Ventral skin of upper hind limb of Atelopus varius from western Panama. Two sporangia (spore-containing bodies of Batrachochytrium sp.) containing numerous zoospores are visible within cells of the stratum corneum. Each flask-shaped sporangium has a single characteristic discharge tube (arrows) at the skin surface. Exiting zoospores are visible in the discharge tubes of both sporangia. Source: Daszak P, Berger L, Cunningham A, Hyatt A, Green D, Speare R. Emerging Infectious Diseases and Amphibian Population Declines. 1999 Nov-Dec. BUT YOU SAID THAT THE CHYTRID FUNGUS HAS BEEN DEVASTATING AMPHIBIAN POPULATIONS IN REGIONS AS REMOTE AND SEPARATE AS BRAZIL AND THE CALIFORNIA MOUNTAINS. Yes. The only explanation that has come up that makes any global sense is the transportation of the African clawed frogs around the world. That is purely an hypothesis. There is no strong evidence for that, but that’s all we’ve got. I don’t know how this fungus is getting around. WHY IS IT THAT THE WAY THE CHYTRID FUNGUS IS KILLING AMPHIBIANS IS STILL NOT UNDERSTOOD? Very good question. There are a lot of people working on that. It’s a difficult question. I can tell you that the number of amphibian experimentalists has increased dramatically in the past couple of decades, but we still do not know the answers to those questions. Fungi are really hard things to study. Fungi are tough and difficult to get rid of. Have you ever looked at a magazine and seen all the ads for nail (form of keratin) fungus remedies? There are hundreds of fungi that attack different organisms and we are not able to handle most of them. Why do we have so much trouble with fungi? Because they are complex organisms and we haven’t learned our lessons about fungi yet. There are a lot of things we have to learn. 03/11/'09 Amfibieën zijn de meest bedreigde diersoorten op aarde. Dat blijkt uit de jongste Rode Lijst van de IUCN (International Union for the Conservation for Nature) in het Zwitserse Gland. In totaal zijn van de 47.677 onderzochte dier- en plantensoorten 17.291 met uitsterven bedreigd. Vooral de amfibieën hebben het zwaar. Bijna een derde van de kikkers, padden en salamanders is met uitsterven bedreigd. Het milieu en een zich steeds verder verspreidende schimmelziekte zijn de belangrijkste oorzaken. KMa index[1]bedreigde amfibieen europa.pdf Welke reptielen en amfibieën zijn in Nederland bedreigd? Het gaat niet goed met de reptielen en amfibieën van ons land. De meeste soorten gaan hard in aantal achteruit. Dat komt vooral doordat de milieuomstandigheden steeds slechter worden. Allerlei terreinen waar vroeger veel amfibieën en reptielen voorkwamen, zijn nu voor hen niet meer geschikt. Boomkikker Rode Lijst Hazelworm Van de 23 in Nederland voorkomende soorten amfibieën en reptielen staan er 15 op de Rode Lijst van 1996. De eerste Rode Lijst was in 1986 verschenen. Toen werden er drie soorten beschouwd als 'zeer ernstig bedreigd', zeven als 'ernstig bedreigd', vijf als 'bedreigd', twee als 'mogelijk bedreigd' en zes als 'niet bedreigd'. Sindsdien is de stand van veel soorten verder achteruitgegaan. Kamsalamander Ringslang In 1996 werden de volgende categorieën onderscheiden: 'Ernstig bedreigd': geelbuikpad ( Bombina variegata ) muurhagedis ( Podarcis muralis ) 'Bedreigd': vuursalamander ( Salamandra salamandra ) knoflookpad ( Pelobates fuscus ) boomkikker ( Hyla arborea ) gladde slang ( Coronella austriaca ) 'Kwetsbaar': kamsalamander ( Triturus cristatus ) vinpootsalamander ( Triturus helveticus ) vroedmeesterpad ( Alytes obstetricans ) poelkikker ( Rana lessonae ) heikikker ( Rana arvalis ) hazelworm ( Anguis fragilis ) zandhagedis ( Lacerta agilis ) ringslang ( Natrix natrix ) adder ( Vipera berus ) De overige acht soorten staan genoteerd als 'thans niet bedreigd' Rode lijst Amfibieën (RAVON) SNA N Van de 16 in ons land voorkomende amfibieën staat er 9 op de rode lijst. De geelbuikvuurpad is zeer entig bedreigd in ons land. De kans dat je hem nog in het wild tegen zult komen is helaas erg klein. Iets minder bedreigd, maar wel zeer zeldzaam zijn de vuursalamander, boomkikker en de knoflookpad te noemen. De kamsalamander, de vinpootsalamander, de poelkikker, de heikikker en de vroedmeesterspad gaan in popolulatie de laatste jaren ook zorgwekkend hard achteruit. STATUS 1996 Vuursalamander bedreigd Salamandra salamandra Kamsalamander kwestbaar Triturus cristatus Vinpootsalamander kwetsbaar Triturus helveticus Vroedmeesterpad kwetsbaar Alytes obstericans Geelbuikvuurpad ernstig bedreigd Bombina variegata Knoflookpad bedreigd Pelobates fuscus Heikikker kwetsbaar Boomkikker bedreigd Hyla arborea Rana arvalis Poelkikker kwetsbaar Rana lessonae Een overzicht van oorzaken voor de achteruitgang: Versnippering Verzuring Vermesting vergrassing Verdroging Wegvangen X X Vuursalamander X Kamsalamander X X X X Vinpootsalamander X X X X Vroedmeesterpad X X Geelbuikvuurpad X X Knoflookpad X X X X Boomkikker X X X X Heikikker X X X X Poelkikker X X X X X X Over de rode lijst... Deze rode lijst is opgesteld volgens een voor Nederland ontwikkelde gestanddaardiseerde methode, afgeleid van de internationaal gehanteerde methode die door de International Union for Conservation of Nature and Natural Resources (IUCN) is ontwikkeld. De rode lijst voor reptielen en amfibieën is uitgegeven door IKC natuurbeheer in Wageningen (rapport nr. 25). Het basisrapport Bedreigde en kwetsbare Reptielen en Amfibieën in Nederland is een uitgave van Stichting RAVON te Nijmegen (RAVON publicatie 1996-2). Naar Rode Lijst Reptielen Naar RAVON.nl Duizenden soorten amfibieën nog niet ontdekt maar reeds met uitsterven bedreigd 18/05/11, Eén van de bedreigde amfibieën: de klauwkikker in dierentuin Artis. © ANP Zeker drieduizend soorten amfibieën zijn nog niet door de mens ontdekt. Het zou gaan om kikkers, padden en salamanders die met uitsterven worden bedreigd, nog voordat ze ooit zijn onderzocht. Onderzoekers melden deze bevindingen in het wetenschappelijke tijdschrift Proceedings of the Royal Society B. De onderzoekers denken dat de nog te ontdekken dieren, waaronder 160 soorten zoogdieren, zich vooral in tropisch regenwoud bevinden. Onder meer rond de Amazone in Zuid-Amerika, op het eiland Nieuw-Guinea bij Indonesië en Australië en in het gebied rond de rivier de Congo in Afrika zouden nog veel soorten te vinden zijn. Kleine dieren De schatting is gebaseerd op de nog niet in kaart gebrachte hectares land en op het aantal dieren dat tijdens eerdere expedities werd ontdekt. De laatste jaren worden geen grote dieren meer ontdekt, maar vooral veel kleine soorten. Onderzoekers bekijken daarom tegenwoordig kleine delen bos heel grondig. Gehoopt wordt dat de tropische wouden snel beter worden beschermd, zodat de nog onbekende dieren niet op korte termijn uitsterven.