The name derives from the valley of the freshwater pearl mussel, which used to be native to riverbed colonies. Today, it is considered almost extinct here as well. Only a few ancient specimens are preserved in a hidden place, which is made known only to scientists because of the danger of negligent destruction.
From 1668 to 1880, the pearl mussels were exclusively used by the prince of the Duchy of Jülich through the use of a pearl shelf. The pearl fisherman Benedikt Ossenbruch, who had been appointed by him, used them economically. For the purpose of sufficient deterrence against secret "wild-fishing", a gallows was erected in 1746 on the still existing "Galgendamm". Whether "pearl robbers" were actually put to death there is not known. After the occupation of the country by Napoleonic troops, the Perlregal was lifted and the mussels of greed and depredation more and more delivered. From 1880, historical sources testify that a Monschau-based manufacturer had carts of pearl-shells transported away, but only scrapped very little yield of black river pearls. A restaurant "At Court" continues to testify locally of the history.
The nutrient-poor meadows of the Bachtal valley were used for centuries to harvest hay until modern, intensified agriculture abandoned the remote fields as uneconomic. Instead, mainly fast-growing spruce trees were planted to still achieve economic benefits. Only the becoming active of homeland and nature conservationists within the German-Belgian nature park High Venn-Eifel brought a turning point. The North Rhine-Westphalia Foundation purchased large tracts of land for nature conservation. In subsidized care programs, farmers resumed the traditional mowing to conserve these meadow biotopes.
Source: Wikipedia
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