The grayling ...
... beautiful and threatened
thymallus thymallus
... it is considered to be the most colorful local fish, it is the leading fish of the river region of the "grayling region" and fish of the year 2011. But the "flag bearer" has become a rarity in our waters or has completely disappeared. Grayling stand in the middle water, show no escape behavior and do not seek cover like brown trout would. So they are usually the first to fall prey to the invading cormorants.
In most cases, however, water pollution from agriculture and industry, but also the construction of rivers and the associated reduction in shallow water zones, which are indispensable for larvae and juveniles, as well as the warming of the water is a main reason for a decline in stocks.
The grayling Thymallus thymallus due to the large, striking dorsal fin also called the flag bearer belongs to the family of salmonids (salmon-like).
In many places, committed associations are trying to preserve the species in their waters through stocking measures. However, it is scarcely possible to support established tribes with outside stocking. It is more promising to remove parent animals from existing populations that have already undergone a regional adaptation genetically. By breeding these animals it is possible to rebuild a stock "from below". It is a misconception that the use of adult animals is the right way. These can usually not adapt and contribute little, if any, to the natural reproduction of inventory.
The search begins ...
... so it happened that in 2018 we started looking for a source for suitable grayling parents or fertilized eggs. Only a few are dedicated to the breeding of grayling, as a rule, breeders encounter animals that have been imported from Sweden / Denmark, if any statements about their origin are made. Our colleagues from Switzerland recognized the signs of the times and started a breeding program very early on. But after several conversations it was clear that no suitable material could be obtained here either - the Rhine Falls near Neuhausen represent a natural obstacle to hiking and the grayling trunks above and below differ genetically too much to be able to bring them into our waters.