Yellow-Bellied Toad
- Class: Amphibian
- Order: Anura
- Latin name: Bombina Variegata
- Range: From Central-/Eastern Europe to Mediterranean region
- IUCN Status: LC (Least Concern) / Cites: Not listed
(Above classifications are a 2008 situation).
In the strictest sense of endangerment it perhaps would not qualify for this series (from endangered species), as it is only counted LC in the IUCN list and not disappearing so fast as would mean the classification of seriously threatened. But, fx subspecies Apennine Yellow-bellied Toad (Bombina pachypus), found only in Italy is listed as endangered(EN) because of its fast decline. Further, including Bombina variegata here becomes more justified if examining the situation of amphibians in whole. Findings of the European Red List of Amphibians1 give some hint about the scope of overall decline: in addition to about 15 or more severely endangered - including critically endangered Karpathos Frog(Pelophylax cerigensis) and Montseny Brook Newt(Caloritron arnoldi) - more than half (59 per cent) of the (European) amphibian species populations were in decline and only 36 per cent found in stable state. Main significant threats found (for the amphibians) are; 1st -Habitat loss (mankind caused loss of natural habitat and suitable living area), 2nd -Pollution (including causes related to climate change), 3rd -Invasive alien species (and some hazardous diseases that affect frogs particularly, such as Chytridiomycosis) (p. 11-13 in that IUCN survey mentioned – see the note before). Looks like hard times for frogs, since their general disappearance and declining populations has already been seen happening for some decades, at least.
More conventional and typical reasons for amphibian decline are human caused habitat destruction and urbanization; major ones also include the drying of wet-lands, road construction, water pollution. In addition to those comes the increased land cultivation and agriculturalism, but there's yet several other factors and in general decline is mostly seen a result from various reasons (as often summarised in final conclusive sentences). But, one also finds, among the most significant reasons there is also the overall increase of toxins and use of chemical contaminants(pesticides and some fertilizers, – particularly concerning the amphibians has been the Atrazine, herbicide used about since 1950s, although its more recently been banned in European Union) ; Another, probably more recent, but also mentioned as threat is the raises in UV-B Radiation ; And there's yet more conventional/regular reasons, like the animals being collected for food, pets, etc.
So, on the basis discussed things, our example here Bombina Variegata (Yellow-bellied Toad) fits more than adequately to present here in our series from endangered species. Even though it is a common species and not in immediate danger of extinction, seems quite plausible that future seems to hold plenty of things that could cause it becoming so. Wikipedian heading from the decline in the class/taxa also points out a fact not yet mentioned: due that amphibians have two-part life-stages(ie in brief are generally dependable from both aquatic and terrestrial conditions in during life-cycles), they are more vulnerable to human caused changes for world's biodiversity than some other animals. Whatever the most potential reason, globally alarming thing is the extinction rate, according to conservative estimates about 200 times the past rate(if compared to overall amphibians background extinctions from the past).
But, since we don't want end this post in too depressive comments, we'll finally here also remind ourselves that the amphibians have a long evolutionary history, far longer than man. And, as mentioned before, their reproductivity potential gives yet some reasons to optimism also. As well, there's also much not yet known from them; fx frogs are mentioned returning to the same places(ponds, fx) for breeding each year, which is some kind of mystery too, exact reasons unknown, if not for the frogs themselves - Only that one hopes those ponds to remain there in the future still...
Notes: 1. Temple, H.J. And Cox, N.A. 2009, European Red List of Amphibians. Luxembourg. Office for Official Publications of the European Communities. – The report available from: http://www.iucn.org/about/work/programmes/species/?3204/Europes-amphibians-and-reptiles-under-threat--- → under downloads/European Red List of Amphibians (pdf). (A studies carried by IUCN for European Commission) 2. Pounds, A.J. , 2001. Climate Change and Amphibian Declines. Nature 410; 639-40. [Cited via: Flannery, Tim, 2005. The Weather Makers. The history and Future Impact of Climate Change.] 3. Or, the diseases name may be a synomous to Chytrodimycosis(?), since its also fungus-related and Flannery mentions it as one cause in the annihilation of frog species around the world. Whatever the case, a quick search from Wikipedia didn't give us any direct answer/clarification to that important terminological question...Possibly, the term is such a new one, that it's not in any common use yet(?)... (The free Dictionary by Farlex returns us a definition from Saprolegnia Ferax (not from Saprolgenia Ferax): "A fungus that attacks living fish and tadpoles and spawn causing white fungus disease: a coating of white hyphae on especially peripheral parts (as fins)" (though, as the results from the study mentioned seem to date as far as 2001, and probably more recent research has surfaced since then, but those search results, especially the terms absence of directories and definitions, seem just...unlikely. [?]) ----------
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