Threats for amphibians

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In areas covered by the project, there occur the following risks, having a negative impact on the species of amphibians and their habitats:

Amphibians mortality on roads

Amphibians seasonal migrations are often of mass character. During a short period of time, thousands of amphibians roam, facing various barriers on their way, including communication routes. Especially important is the period of spring migrations. Most of the amphibians being killed by cars are sexually mature individuals, and thus prepared for breeding, often in the stage of mating in amplexus. Migration periods therefore have a significant impact on the stability of amphibians populations. For some species occurring in small numbers in our country and throughout Europe, even a small reduction in number of individuals is a threat for the population in the given area.

Construction of underground tunnels across the road (action C.1), in areas where there has been the largest amphibian mortality on roads, can help to protect these animals and maintain the proper size of their populations; this risk occurs in all areas of the project and applies to all species of amphibians, especially the Common toad, Common frog, Moor frog, Pool frog and the European common frog.

The disappearance of amphibians breeding places

Amphibians, including fire-bellied toad (Bombina bombina) - code 1188, European common spadefoot (Pelobates fuscus) and Northern crested newt (Triturus cristatus) - code 1166, they all need ponds for breeding. The perfect breeding place for most amphibians are small, shallow, mid-forest and mid-field ponds. Their morphometry and location, however, contribute to their rapid shallowing and overgrowing. As a result, the water in the tanks is maintained only in the spring, acting in a kind of trap for breeding amphibians. Eggs laid in the water in the spring don't have chance for the full development and while the pond is drying, the eggs die in large numbers.

Restoration of vanishing tanks - removal of these excess plants and sediments (Action C.2), will improve the condition of the population of these animals; this risk occurs mainly in the "Ostoja Wigry" and "Romincka Forest" and applies to all species of amphibians, including the fire-bellied toad ( Bombina bombina) - code 1188 and and Northern crested newt (Triturus cristatus) - code 1166.

Amphibians mortality in so called anthropogenic traps

Amphibians are dying not only being run over by cars, but also falling into various types of traps, from which they can not get out. These traps include, among others, road drainage facilities - sewer drains and wells of rain, collectors and separators, unprotected excavations, ponds with steep banks. Such anthropogenic traps are being formed mainly during the various construction works, eg. during construction of roads, power lines or bridges. Developing technical solutions to protect amphibians (and other small vertebrate animals) from falling into the traps (action C.3), which are both temporary (during construction) and permanent (target solution) elements of the technical infrastructure construction, which will help to reduce the mortality of small animals, including amphibians.

No widely available and sufficient information about where amphibians migration routes are crossing with communication routes

Amphibians occurring along the routes often die run over by vehicles, as their migration routes cross with roads. In such places, culverts for amphibians should be built. However, the lack of information about places of this kind makes it impossible to make such decisions. Monitoring such places, including local communities (Action C.4), will increase the number of culverts built for amphibians, and thus reduce the mortality of amphibians on roads. The places selected for the construction of culverts under the roads within this project have been studied in detail by the staff of the Narew National Park, Romincka Forest Landscape Park and the members of "Man and Nature" Association.