- Journal Details
- Format
- Journal
- eISSN
- 2353-8589
- First Published
- 30 May 2013
- Publication timeframe
- 4 times per year
- Languages
- English
In Poland, 18 amphibian species live in Poland. They represent two orders, namely, salamanders –
Protection status of amphibians in Poland
| Commonfrog | PP | |
| Moor frog | SP | |
| Pool frog | PP | |
| Marsh frog | PP | |
| Edible frog | PP | |
| Agile frog | SP | NT |
| Common toad | PP | |
| European green toad | SP | |
| Natterjack toad | SP/A | |
| European common spadefoot | SP | |
| European fire-bellied toad | SP/A | |
| Smooth newt | PP | |
| Northern crested newt | SP/A | NT |
| Alpine newt | PP | |
| Carpathian newt | SP/A | LC |
| European tree frog | SP/A | |
| Yellow-bellied toad | SP/A | |
| Fire salamander | PP |
SP – strict protection, SP/A – strict protection requiring active protection, PP – partial protection, NT – near threatened, LT – least concern
Source: Regulation of the Minister of Environment of 6 October 2014, on the protection of animal species (Journal of Laws No 2014, item 1348), Krzysztofiak L., Krzysztofiak A., 2016. Active protection of amphibians, the “Man and Nature” Association, Krzywe, p. 68, IUCN 2020.
Amphibians are among the most endangered vertebrate species worldwide. At the European level, nearly 23% of the amphibians have been recognised as endangered, of which 2.4% as critically endangered, 7.2% as endangered and 13.3% as vulnerable. A similar situation is observed throughout the EU-27 (22.0% endangered, including 2.4% critically endangered, 6.1% endangered and 13.4% vulnerable). In general, almost a quarter of amphibians are regarded as endangered on the European continent. Further, 16.9% of the amphibians are regarded as near threatened. By way of contrast, 19.4% of the reptiles, 15.2% of the mammals and 13% of the European birds are endangered [Temple, H.J., Cox, N.A., 2009].
As regards amphibians, the greatest threat is the loss of habitats, which affects a total of 76 species. Contaminants are the second major threat that affects 62 species. They are followed by invasive alien species, which pose a threat to almost half of the European amphibian species. These invasive species include predators, such as the salmonids, and pathogens, such as a fungal disease chytridiomycosis, which is associated with a reduction in the amphibian population numbers, and the extinction of amphibians in many parts of the world
Another serious threat is the uptake of water resources (particularly for agricultural purposes), which changes the hydrology of surface waters of the habitats inhabited by amphibians [Mathwin R. et al., 2002]. The fragmentation of habitats, which contributes to the loss of biological diversity worldwide, is also of extreme importance. The fragmentation implies a reduced gene flow, an increase in the inbreeding levels, the loss of diversity in populations, an increased differentiation between populations and the increased risk of extinction and the dispersion (i.e. from the site of birth to the reproduction in other population) [Pabijan M. et al., 2020; Winter M. et al., 2016; Testud G. et al., 2020].
One of the factors contributing to the fragmentation of habitats is the network of roads, particularly the local ones. Amphibians are dependent on the complex landscape structure when moving between breeding and feeding habitats. Roads act as barriers: they increase the imperviousness of habitats and mortality of amphibians. Unfortunately, the mass mortality of amphibians on the roads increases with the development of infrastructure and occurs faster than mitigating measures [Kolenda K. et al., 2019]. Consequently, the fragmentation of habitats results in the fragmentation of population, modification of animals’ behaviours and a reduction in gene flow [Puky M., 2006; Sillero N. et al., 2019; Wittbrodt K., 2011; Sjögren-Gulve P., 2020]. In addition, the roads, due to the need for maintaining them (e.g., sand or salt spreading on icy roads), change and pollute the habitats located in the immediate vicinity, which can have a lasting effect on the biology of organisms, the population dynamics and the distribution of species [Grzybowski M., Glińska-Lewczuk, 2019]. The fragmentation of habitats in the form of road infrastructure development has an adverse effect on:
an amphibian’s individual characteristics within the same species (certain individuals, especially females, mature earlier, while others do it later), ecological and hydrobiological differences, even between neighbouring water bodies in which amphibians mate, differences in meteorological conditions, taking place primarily during the growing periods of individual years (dry, wet, warm and cold growing periods) [Juszczyk W., 1987].
It is believed that it is the climate change that is of significance in the shaping of amphibian population. Ectothermic animals such as amphibians and reptiles are particularly sensitive to the rapidly rising global temperature [Bodensteiner B.L., 2020; Taylor E.N. et al., 2020]. According to Bucciarelli G.M. et al. [2020], although the amphibians have developed life strategies in order to mitigate the adverse consequences of varying precipitation patterns, their ability to adapt to the simultaneous drought and rapid increased in the temperature as well as the greater environmental variability in general, may be insufficient to maintain viable populations, given the rate and intensity of these changes. A study by Cohen J. M. et al. [2018] demonstrated that global warming may have consequences for the amphibians adapted to relatively cold conditions, which are most vulnerable to the interactions between an increase in the average temperature and the emerging infectious diseases. Yiming LI Y et al. [2012] express a different opinion, as they claim that there is little evidence of climate change being lethal to amphibians. These authors believe that the information on thermal tolerance of amphibians, their thermal preferences and the actual temperature and humidity ranges in which amphibians live is too limited.
The examples provided above have resulted in eight out of 18 species having been awarded the UI (unfavourable-inadequate) status in the European Union. These species include: European common spadefoot Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora, OJ L 206, 22.7.1992, pp. 7–50, IUCN (2020).
In Poland, all amphibian species are subject to legal protection, of which three species are under strict protection, while for six species, active protection was proposed (Table 1).
The unfavourable situation in the context of changes in populations of individual amphibian species necessitates taking remedial measures such as the development of programmes for construction/reconstruction of water bodies, which increase the diversity of plants and invertebrates as well as amphibians, programmes for Eurasian beaver reintroduction and the construction of road-crossing tunnels for amphibians in the road infrastructure [Downie J.R. et al., 2019; Klimaszewski K. et al., 2015; Dalbeck L. et al., 2020].
It is very important to create natural buffers between wetlands and the surrounding areas, which will consequently have a positive effect on water quality and biological diversity. Buffer zones are contact zones between aquatic and terrestrial ecosystems, which help regulate the ecological functions of both systems. As regards the amphibians, an effective buffer zone should be approximately 50 m wide [Lind L. et al., 2019; Guzy J.C. et al., 2019].
However, the research conducted in Canada, the United States and Italy showed that the guidelines concerning the protection of true frogs
The aim of monitoring was to determine the dynamics of changes in population numbers of amphibians
Figure 1
The location of field research
Source: Own research
The reserve was established on 22 April 1983 by Order of the Minister of Forestry and Wood Industry. The main aim of the reserve’s protection is to protect forest, aquatic and peat bog biocenoses associated with the Upper Krutynia River Valley and the Lake Krutyńskie and the natural landscape features. The reserve has a landscape park character, and its area is 271.01 ha. The reserve protects the Lake Krutyńskie and the upper section of the Krutynia River, which flows out from the lake, and the leafy and mixed forests located by the river banks [Wittbrodt K., et al., 2020]. Order of the Minister of Forestry and Wood Industry of 22 April 1983 on the recognition as nature reserves [M.P. of 1983, No 16, item 91]. Order of the Regional Director for Environmental Protection in Olsztyn of 7 May 2019 on the “Krutynia Górna” Nature Reserve [Journal of Laws of Warmińsko-MazurskieVoivodeship of 2019, item 2375].
In the years 2011–2019, at the turn of February and March, barriers were placed on both sides of a 200-m-long section of the district road 1773N adjacent to the reserve, in order to prevent amphibians from crossing the road (Fig. 2). Along the barrier, from the inside, plastic traps were embedded in the ground (8 on each side). The traps had holes in them so that no water accumulated in them during rainfalls; moreover, branches were placed in them to allow insects and small-sized mammals to escape from the trap [
Figure 2
Average annual values of the temperature, total precipitation and the climatic water balance during the spring period (from March to May) in the Masurian Landscape Park in the years 2011–2019. (P – precipitation, ETP – potential evapotranspiration, S – climatic waterbalance, T – the average annual air temperature)
Source: Own research
Depending on the air temperature and humidity, the monitoring was conducted 2–3 times a day. The temperature was measured, and the weather conditions were determined. The monitoring personnel checked the traps located on one side of the road, identified the species composition and counted the trapped individuals and then transferred them to the other side of the road. The barriers were removed in the first half of May, when amphibians finish their migration to breeding sites.
Each year, before commencing the monitoring, the Regional Director for Environmental Protection in Olsztyn was applied to for permission to trap the protected species individuals.
During the period under study, the average spring period temperatures were 8.1°C and were higher by 0.9°C than the multi-annual average temperatures of 1981–2010 [Dragańska et al., 2019]. The average temperature values for individual months of the spring period were also considerably higher than in the years 1981–2010. The difference was 0.8°C in March and May, and 1.0°C in April. The total precipitation in the spring (from March to May) was 122.2 mm and did not deviate from the multi-annual norm of 126.9 mm (Fig. 2). The total precipitation values in individual months, that is, in March, April and May, also fell within the standard limits, which, for the multi-annual period of 1981–2010, amounted to 34.7, 32.1 and 60.1 mm, respectively [Dragańska et al., 2019].
In the situation of a significant rise in the air temperature, and in the absence of a clear trend in precipitation changes, the climatic water balance, which is determined as a difference between the precipitation and the evapotranspiration, was used for the assessment of the shaping of humidity conditions for the particular area [Ziarnicka-Wojtaszek A., 2015; Radzka E., 2014]. The comparison of the losses of water used for evaporation and the total precipitation allows the humidity habitat conditions to be diagnosed. The value of this indicator during the spring period in individual years of the study ranged from −3.0 mm in 2012 to −100.4 mm in 2018. Occasionally, situations were noted where the KBW values in individual months of the analysed period were positive. This means that the situation as regards the humidity conditions of the habitats under study was not favourable (Fig. 2).
In the years 2011–2019, in the area selected for the study, a total of 30,563 individuals (Fig. 3) that represented six families and 13 domestic amphibian species were trapped. Among these, the true frogs (
Figure 3
Amphibian population numbers in the years 2011–2019
Source: Own research
Amphibian population numbers in terms of affiliation to individual families
| True frogs ( | 22,253 | 84.9%. |
| True toads ( | 3,208 | 12.2% |
| True salamanders and newts | 649 | 2.5% |
| European spadefoot toads ( | 92 | 0.3% |
| Firebelly toads | 17 | 0.1% |
| Tree frogs | 4 | 0.02% |
Source: Own research
Population numbers for individual amphibian species in the years 2011–2019
| 684 | 2,730 | 1,458 | 3,620 | 2,631 | 2,871 | 466 | 1,011 | 204 | |
| - | 81 | 2 | 124 | 468 | 554 | 200 | 1,368 | 3,026 | |
| - | 2 | 17 | 48 | 330 | 49 | 50 | - | 230 | |
| - | - | - | - | 17 | - | 31 | - | - | |
| 449 | 520 | 640 | 890 | 219 | 134 | 135 | 454 | 305 | |
| 535 | 649 | 374 | 342 | 380 | 263 | 259 | 401 | 299 | |
| - | - | - | - | - | - | - | 4 | 1 | |
| 1 | - | - | - | - | - | - | - | - | |
| 1 | 5 | 11 | 6 | 17 | 4 | 21 | 27 | 7 | |
| - | - | 3 | 2 | 2 | - | 5 | 5 | 1 | |
| 17 | 31 | 17 | 48 | 108 | 358 | 17 | 39 | 147 | |
| 16 | 6 | - | 23 | 8 | 34 | 47 | |||
| 1 | 2 | - | - | - | - | 1 | - | - | |
Source: Own research
Having analysed the number of amphibians in individual years, it was concluded that most of them occurred in 2014 (5,080), that is, in the year following the record-braking droughts of 2012 and 2013 (Fig. 2), while the least of them occurred in the years 2017 (1,193) and in 2011 (1,688). Over a period of nine years, the dominant species in the area concerned was the common frog
The species that only occasionally occurred in the part of the Masurian Landscape Park under study included: the natterjack toad (
The results of amphibian monitoring carried out in the years 2011–2019 in the Masurian Landscape Park, in the vicinity of the “Krutynia Górna” Nature Reserve, showed the occurrence of 13 out of the 18 domestic amphibian species, including the Northern crested newt
Figure 1
Figure 2
Figure 3
Population numbers for individual amphibian species in the years 2011–2019
| 684 | 2,730 | 1,458 | 3,620 | 2,631 | 2,871 | 466 | 1,011 | 204 | |
| - | 81 | 2 | 124 | 468 | 554 | 200 | 1,368 | 3,026 | |
| - | 2 | 17 | 48 | 330 | 49 | 50 | - | 230 | |
| - | - | - | - | 17 | - | 31 | - | - | |
| 449 | 520 | 640 | 890 | 219 | 134 | 135 | 454 | 305 | |
| 535 | 649 | 374 | 342 | 380 | 263 | 259 | 401 | 299 | |
| - | - | - | - | - | - | - | 4 | 1 | |
| 1 | - | - | - | - | - | - | - | - | |
| 1 | 5 | 11 | 6 | 17 | 4 | 21 | 27 | 7 | |
| - | - | 3 | 2 | 2 | - | 5 | 5 | 1 | |
| 17 | 31 | 17 | 48 | 108 | 358 | 17 | 39 | 147 | |
| 16 | 6 | - | 23 | 8 | 34 | 47 | |||
| 1 | 2 | - | - | - | - | 1 | - | - | |
Protection status of amphibians in Poland
| Commonfrog | PP | |
| Moor frog | SP | |
| Pool frog | PP | |
| Marsh frog | PP | |
| Edible frog | PP | |
| Agile frog | SP | NT |
| Common toad | PP | |
| European green toad | SP | |
| Natterjack toad | SP/A | |
| European common spadefoot | SP | |
| European fire-bellied toad | SP/A | |
| Smooth newt | PP | |
| Northern crested newt | SP/A | NT |
| Alpine newt | PP | |
| Carpathian newt | SP/A | LC |
| European tree frog | SP/A | |
| Yellow-bellied toad | SP/A | |
| Fire salamander | PP |
Amphibian population numbers in terms of affiliation to individual families
| True frogs ( | 22,253 | 84.9%. |
| True toads ( | 3,208 | 12.2% |
| True salamanders and newts | 649 | 2.5% |
| European spadefoot toads ( | 92 | 0.3% |
| Firebelly toads | 17 | 0.1% |
| Tree frogs | 4 | 0.02% |