The district fishing association points out the schwabach as the habitat of salmonid waters, where you can also observe rare animals like the kingfisher or the grass snake. The schwabach rises near igensdorf in the district of forchheim. Southeastward it then flies to forth (district erlangen-hochstadt) and from there in a westerly direction to erlangen to mouth right into the regnitz river. The schwabach valley includes the communities of igensdorf, eckental, kleinsendelbach, neunkirchen am brand, dormitz, uttenreuth and buckenhof, and finally erlangen. In total, the schwabach is 32 kilometers long.
The water management authorities have designated the schwabach as salmonid water. A salmonid water is defined as a stream or river in which fish such as trout (salmo trutta) and grayling (thymallus thymallus) live, whose habitat must be preserved by means of care and maintenance by persons trained for this purpose. Furthermore, the waters are classified due to heavy metal contamination. Since the fish mentioned are very sensitive to this pollution, only the least polluted waters can be designated as salmonid waters.
The most important fish
The most important fish in this ecosystem is the brook trout, a predatory fish. Brown trout can grow up to 80 centimeters long and 18 years old. But usually the trout are between 35 and 45 centimeters coarse. The dark back protects them from predators such as the heron from above, as they are camouflaged above dark ground. During the day, it usually hides in the shadows of the banks with its head turned against the oxygen-rich, shallow current. It feeds mainly on small insects and insect larvae living in the water, but also on small fish, crustaceans and snails.
Faithful to the location
As a fish that is loyal to its habitat, the brown trout always returns to the same spot and defends its territory against other trout. Only for reproduction the trout swims back to its birthplace in the cold gravelly upper reaches of the creek. However, the construction of mills has cut off this path. Cross-barriers like the weir at the head clinic in erlangen are usually insurmountable hurdles for the brook trout.
Accordingly, the stream habitat must be stocked by the district fishery association with breeding trout, which have the "smell" of the stream their birth waters are no longer natural "in the nose have, since they saw the light of day in breeding facilities.
Careless breeding trout
Various dangers lurk in the waters for the careless breeding trout, for example from predators not suited to the habitat, such as pike and perch, which have either been introduced into the schwabach through spawning on duck pens or have escaped from one of the breeding ponds in the upper region. Cormorants, which eat up to 1.5 kilograms of fish (about three trout) a day, also pose a serious risk.
In the yolk sac stage
For these reasons, the erlangen district fishing club, under the guidance of water conservation officer nikolaus schadt and chief water warden achim poesdorf, decided to stock young trout at the yolk sac stage. At this early age the trout are still given the necessary information about the birth waters. Furthermore, they quickly learn to hide in the current from current pressure and predators.
By the youth leaders eric blank, karsten hull and jochen maier the topic was discussed in the youth group. In the run-up to the event, the waters in the upper reaches were first sighted for favorable water sections without deep pools, which offer fish robbers a favorable hiding place.
Breeding from the seabed
After a long search, the right trout could be ordered in aufseb (bayreuth district).
The freshly hatched trout in the yolk sac stage were transported to the schwabach in oxygen-supplied traps. First, the temperature of the water was compared with the temperature in the tanks and buckets were filled with fresh water from the schwabach river. Then two youngsters at a time were given trout buckets by nikolaus schadt, in order to stock them as quickly as possible in the previously selected, usually difficult to access places. Immediately the small trout disappeared in the gravelly water sections between the stones in order to hide themselves.
This was repeated on several water sections up to 400 meters long.
70 percent survived
A total of about 4000 young trout were stocked by six juveniles with the help of six adults. According to results from similar stockings, it can be assumed that up to 70 percent of the young trout will survive. With a lot of new knowledge and curiosity about how the trout will fare in the next few years, the event in kleinsendelbach ended after four hours.
In order to create a healthy age structure in the brook trout population, it is planned to carry out such stockings again and again in the coming years. The stocking of the schwabach in the urban area and upper reaches with crayfish in 1998 and 2002, also under the direction of nico schadt, has been proven to have already led to a very good result according to the fishery association.