Consequently,
Cheseaux-noréaz: staggering decline batracians:
Biodiversity in danger
The staggering decline of the Batracians in Cheseaux-Noréaz – Cheseaux-noréaz: staggering decline batracians
A study reveals that the populations were divided by three in three decades. Furthermore, Are the tunnels supposed to protect their migration inappropriate?
In the space of thirty years, 75% of the common toads have disappeared between Yverdon and Yvonand.
Jean-Paul Guinnard/Tamedia (Archives)
- The common toads populations have dropped 75% in thirty years during spring migration.
- Rieuse frog and agricultural pesticides threaten the populations of amphibians.
- The association of the Grande Cariçaie recommends improving passages to save species.
The cheseaux-noréaz: staggering decline batracians Southern Batracians of Great Cariçaie This is very rare. Consequently, to the point that their workforce has been divided by three in thirty years in the Kesaux-Noréaz area. Meanwhile, “While the migratory populations of frogs. For example, toads were estimated at more than 15,000 individuals in the early 1970s, only a few hundred individuals have been observed in recent years,” notes the association which watches over the nature reserve.
This publishes a study Compiling the counts carried out for three decades. Consequently, when the amphibians have been taken in traps via the three sectors with sixteen tunnels developed under the cantonal strike of strikes between Yverdon-les-Bains and Yvonand (6,500 vehicles per day). Meanwhile, Thus, some 3000 amphibians of all kinds were counted in 1992, against around 1000 in 2024.
“An alarm signal” for amphibian populations
Between the first eleven years of follow -up. the last eleven, during the prenuptial migration which takes place between March and April, the squad of common toads – one of the most widespread species in Switzerland – shows a decline of 75%, that of the red frogs of 66%. “An alarm signal on the poor condition of these populations. ” comments the report, which stresses that “the number of migrant individuals of these two species has passed very close to zero between 2010 and 2015”. Only the different newts have shown a favorable development since 2013.
How could the Batracian populations be so decimated? The association of the Grande Cariçaie lists several negative factors: “The strong presence of the laughing frog in the ponds. the impact of the agricultural zone upstream (fertilizer, pesticides) and the poor functionality of the passages with existing cheseaux-noréaz: staggering decline batracians amphibians.”
The cantonal road between Yverdon and Yvonand is equipped with passages for the Batracians.
Jean-Paul Guinnard/Tamedia (Archives)
Toadlines ill -suited to amphibians
Indeed. if the decline had been initiated for a long time, since in 1983 the number of Batracians was estimated at around 5000 or 6000 individuals, it continued despite the construction of toaducts in the late 80s. The study raises the hypothesis cheseaux-noréaz: staggering decline batracians that these passages are poorly suited. with their tunnels a few tens of centimeters wide when the current norm advocates a meter. The improvement of access slopes to the railroad tracks. the creation of rail passages, on the other hand, seem to have had a positive effect.
In an attempt to stop the decline of the populations of amphibians. Additionally, the Great Cariçaie believes that it is necessary to quickly make the repair and the extension of the passages to amphibians, as well as to the improvement of the permeability of the railways. Field investigations will target points where to strengthen the passage in priority.
“The Vaudois week”
Find most of the news of the canton of Vaud. every Friday in your mailbox.
Other newsletters
Did you find an error? Please report it to us.
Further reading: The access road to the Big Dixence dam will not reopen before mid -August – RTS.CH – Swiss literature: ten French -speaking surveys in search of a national prize – National cohesion: defend languages, before the Swiss no longer understand themselves – No agreement between Switzerland and the United States – A symbol of friendship and partnership.
