Global and European regional assessment: Least Concern (LC)
EU 27 regional assessment: Least Concern (LC)

This European endemic species is assessed as Least Concern both globally and for the EU27 member states in view of its wide distribution, tolerance of a broad range of habitats, presumed large population, and because it is unlikely to be declining fast enough for listing in a threatened category.

This species is found throughout much of Europe, ranging from the French Atlantic coastline eastwards to the Ukrainian Carpathians, Romania, and Bulgaria and widely distributed in the Balkans, south to Greece (Pindos in northern Greece, western Central Greece and in north Peloponnese; E.-A. Toli, Greece national Red List). Isolated subpopulations are present northern Poland (Gdansk), southern Italy and northern Spain, but it is absent from Portugal. The distribution map is based largely on Denoël et al. (2001). The species occurs from sea level to around 2,500 m asl (Switzerland and French Alps).

It has been introduced in other parts of Europe, outside of its native range, e.g. in the United Kingdom and in the Sierra de Guadarrama (Madrid Province, central Spain), and has also been introduced to New Zealand (Arntzen et al. 2016).

The species is generally common in suitable habitat. The species is considered to be rare in Hungary and Bulgaria; threatened in Austria and Denmark; vulnerable in Spain (Ichthyosaura alpestris cyreni) and endangered in Ukraine (S. Litvinchuk, pers.comm.). Local declines have been observed in Italy, Albania and Montenegro, due to fish introductions, however, it is still observed in good numbers (F. Ficetola and R. Manenti pers. comm. September 2019; R. Duguet and S.N. Litvinchuk pers. comm. October 2022). Broad-scale declines have been shown in Montenegro (Denoël et al., 2019). Ichthyosaura alpestris inexpectata, endemic to a restricted range of southern Italy, is seriously threatened by the recent introduction of allochthonous fishes (since 2017 carps and since 2019 mosquitofishes) in two of the five sites of presence, and for this reason this subspecies is considered Endangered at national level (I. Bernabò, S. Tripepi, A. Romano pers. comm. October 2022).

This is a mostly aquatic species that is generally found close to water. It is widespread in both alpine and lowland habitats including wet, shaded coniferous, mixed and deciduous forests, sub-alpine meadows and pastureland. It can be found in slightly modified habitats, although it is less common in large cultivated fields. The species breeds, and larval development takes place, in stagnant waters (except large lakes) including shallow ponds, temporary pools, lakes, bogs, ditches, drinking troughs, ruts and sometimes slow-moving streams. Adults can shift ponds during the breeding season (Kopecky et al. 2010). Particularly, they leave fished ponds to join fish free ponds when available at close proximity (Winandy et al. 2017). The generation length can vary between 2–10 years depending on the locality. The species life expectancy might be up to 20 years, but is on average around 7–13 years (Miaud et al. 2000). Several dozens to hundreds of eggs are deposited per female each year. Paedomorphic subpopulations occur almost exclusively in southern Europe (in mountain lakes of Slovenia, Bosnia, Montenegro, Italy and France).

This species is vulnerable to fish introduction and breeding habitat destruction (drainage of wetlands and aquatic pollution) throughout its range (Denoël and Ficetola 2008). Following fish introductions, most populations rapidly become extinct (particularly alternative paedomorphic populations); some taxa (if taxonomy justified) have disappeared following fish introductions (e.g., Ichthyosaura alpestris lacustris (Denoël et al. 2005, 2009, 2019). Forestry activities and traffic by tourists are threatening breeding populations using track pools on forestry roads (Harmos and Magos 2021). In the Balkan countries, an additional threat is the development of “run-of-river” mini-hydroelectric power stations (Crnobrnja-Isailović et al. 2021). In some areas it is collected in excess for use in education and science (this has led to the extinction of the species from some Ukrainian localities). It is also collected in small numbers for the commercial pet trade (especially I. a. inexpectatus of Calabria). Subpopulations in the Peloponnese and southeastern continental Greece are facing severe habitat loss.

Batrachochytrium salamandrivorans (Bsal) is an emerging fungal pathogen affecting amphibians and is closely related to B. dendrobatidis ( Bd), which has had a devastating impact on amphibian populations around the world. Both pathogens cause the infectious disease chytridiomycosis, and both are believed to have originated in Asia (for Bsal: Martel et al. 2014, for Bd: O'Hanlon et al. 2018). While Bd can cause disease in frogs, salamanders and caecilians, Bsal has only been reported to cause disease in salamanders and newts, although the pathogen has been detected in some frog species (Martel et al. 2013). Bd has spread globally, but at present Bsal is only known in Asia and has been introduced to Europe, most likely through the pet trade in salamanders (Martel et al. 2014, Nguyen et al. 2017). Currently in Europe, Bsal has been detected in the wild in the Netherlands, Belgium, Germany (e.g. Thein et al. 2020) and Spain (Martel et al. 2020), and has been shown to be highly pathogenic to most urodelan taxa in Europe (Martel et al. 2014). Laboratory trials for susceptibility to Bsal have demonstrated that this species is moderately susceptible to infection, however, mortality rate varied by dosage with high dosages resulting in high mortality and low dosages with low mortality (Gilbert et al. 2020, F. Pasmans and A. Martel pers. comm. June 2021). Thus, it may be a threat to this species but further research is required to determine the full effects.

Alpine newt is also susceptible to Ranavirus infection (Balsiero et al. 2009) and Amphibiocystidium-infection was detected in laboratory conditions in Switzerland (Oevermann et al. 2007).

In some areas there is over-collection of the species for use in education and science (this has led to the extinction of the species from some Ukrainian localities). It is also collected in small numbers for the commercial pet trade (especially Ichthyosaura alpestris inexpectatus of Calabria). It is presumed that all of these individuals are taken from the wild. Some subspecies are more impacted than others (Denoël et al. 2005, 2009).

Conservation Actions In-Place
This species is present in many protected areas, and strictly protected or protected by national legislation over much of its range. It is listed on Appendix III of the Bern Convention. The species is recorded in a number of national and sub national Red Data Books and Lists. It is considered Vulnerable in Czech Republic (Chobot and Nemec 2017), Slovenia (Anonymous 2010), Hungary (Halpern et al. 2019), Romania (Botnariuc and Tatole 2005), Bulgaria (Golemanski ed. 2011) and Greece (Legakis and Maragou eds. 2009), Near Threaten in Austria (Gollmann, 2007), Data Deficient in Albania (Anonymous 2013). New breeding sites for the species have been created in parts of its range (e.g., Hungary KEHOP-4.1.0-15-2016-00058). In parts of this species range, mitigation measures to reduce road kill have been established.

Conservation Needed
Conservation measures needed include the end of introduction of stocking with fish fry and removal of predatory fishes in mountain lakes and ponds, reduction of overgrazing in mountain pastures, and the restoration of traditional livestock troughs which can serve as breeding sites. The preservation of satellite pools is essential around fish lakes to maintain the species (Denoël et al. 2016).

There is an urgent need to conserve the unique paedomorphic mountain isolates of Ichthyosaura alpestris (Denoël et al. 2005, 2009, 2019) For instance, all paedomorphic endemics from Montenegrin mountain lakes have now disappeared (Denoël et al. 2019).

The preservation of satellite pools is essential around fish lakes to maintain the species (Denoël et al. 2016). There is also an urgent need for a EU (European Union) wide coordinated approach and implementation of the Bsal Action Plan by Gilbert et al. (2020), which was commissioned by the European Commission.

Research Needed
Further research is required on the full effects of Bsal and other emerging pathogens on this species.