|Reference Category||Book chapters|
|DOI / URL||link|
|Title (Primary)||A review of anomalies in natural populations of amphibians and their potential causes|
|Title (Secondary)||Studies on anomalies in natural populations of amphibians = Untersuchungen zu Anomalien in natürlichen Populationen von Amphibien|
|Author||Henle, K.; Dubois, A.; Vershinin, V.L.;|
|Publisher||Henle, K.; Dubois, A.;|
|Volume||25 (Suppl. zu Salamandra)|
|POF III (all)||T12;|
|Keywords||Amphibia; anomalies; hotspots; colour anomalies; disease; edema; individual effects; morphological anomalies; parasites; pollution; population effects; predators; radioactivity; skeletal anomalies; trends; tumours;|
|UFZ wide themes||RU1;|
|UFZ inventory||Leipzig, Bibliothek, Hauptlesesaal, 00521048, 17-0740 DK: 597.6 Stu|
|Abstract||Amphibian anomalies have been a source of curiosity for centuries and the literature on this topic is enormous. We provide a comprehensive overview of the anomalies that have been observed in natural populations of amphibians and discuss their suspected and demonstrated causes. We review the evidence for different sensitivity of species to acquire anomalies and the individual and population level consequences of anomalies as well as their conservation implications. We then go on to review the evidence for an increase in the prevalence of anomalies in natural populations of amphibians over recent decades. Finally, we provide recommendations for future studies and argue that in spite of knowledge gaps, we have sufficient information to reduce the anthropogenic contribution to the plights of amphibians for the sake of amphibian conservation and ecosystem and human health.
For our review we traced any publication on anomalies in natural populations of amphibians starting from our
extensive literature collections. We compiled the published data in a database, treating each species from a particular location as a separate case. Likewise, we entered each population as a separate case, if population specific data were provided for at least one population. In such cases, we ignored additional data provided for lumped populations that included this population.
The earliest documents of amphibian anomalies are provided by the fossil record. Excluding fossils, we compiled data for 3517 natural populations from 98 countries for which anomalies have been reported. These belong to 6, 117 and 386 living species of Gymnophiona, Urodela and Anura, respectively. The oldest definite report of non-fossil anomalies dates back to 1554 and was a toad with malformed limbs. Since the 1860s publications on the topic have appeared almost every year and rapidly increased. Three major increments in the annual number of publications are noticeable, the first occurring after the Second World War, the second in the mid–1970s and the most recent one in 1996 (the year after which malformation hotspots were widely publicized in the USA).
Most published cases involve only one or two individuals (57% of 3034 cases with data). More than 1000 individuals were only affected in 11 cases (9 cases from single populations). Likewise, the vast majority (81% of 3238 cases with data) involved only one or two types of anomalies. Only six cases (four of them being single populations) comprise more than 15 types of anomalies. The highest number (32) was found in a population of the green toad (Bufotes viridis) in Roßwag, Germany.
Abnormal individuals have been reported on all continents, with the vast majority of reports from Europe and
North America. The same applies to hotspots of anomalies. Hotspots differ strongly in the pattern of anomalies. Besides limb anomalies, tumours, edema, colour anomalies (especially albinism) and malformation of mouthparts in larvae were detected with high prevalences at hotspots. Only one hotspot (a population of B. viridis at Roßwag, Germany) showed a high prevalence of various skeletal anomalies, as well as several types of colour anomalies and edema and tumours. The different patterns of anomalies at different hotspots can only be explained by different causative factors or combinations thereof. Opinions on them vary among scientists and their relative importance differs from continent to continent but include chemical pollution, radioactivity, infection by the trematode Ribeiroia ondatrae and other parasites, predator attacks, diseases and various combinations of these factors.
|Persistent UFZ Identifier||https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=19687|
|Henle, K., Dubois, A., Vershinin, V.L. (2017):
A review of anomalies in natural populations of amphibians and their potential causes
In: Henle, K., Dubois, A. (eds.)
Studies on anomalies in natural populations of amphibians = Untersuchungen zu Anomalien in natürlichen Populationen von Amphibien
Mertensiella 25 (Suppl. zu Salamandra)
Deutsche Gesellschaft für Herpetologie und Terrarienkunde (DGHT), Mannheim, p. 57 - 164