Why do salmon come here?
Every year, salmon make their long migration from their hunting grounds in the southern Baltic Sea, often up the Finnish coast, to find their way back to their home rivers and spawning grounds to reproduce. The migration in the rivers starts already in the spring and continues throughout the summer until the spawning season in the fall.
In Fällfors, 28 kilometers upstream in the Byske River from the sea, Skellefteå municipality has a fish counter to follow the migration of salmon and trout for monitoring purposes.
Want to see what's swimming in the river?
Follow the link "Fish counter" to see the camera in Fällfors, Byskeälven. The camera is only in operation when nature allows, often from the end of June-October. Before winter, the camera is taken up for cleaning and winter storage.
In the old fishway on the south side of the river, a fish counter is installed during the season to count fish passing upstream and downstream. This counter is of the so-called optical type and consists of a scanning unit, control unit and photo tunnel.
The counter is mounted at an opening in a concrete wall through which the migrating fish must pass. Through a funnel-like grid, the fish are guided into the counter and through the scanner unit, which consists of two plates sitting opposite each other where passing objects are registered by infrared light. When something passes the scanner plates, the light beams are refracted and the direction, size, shape and speed of the object are recorded in the counter's control unit along with the date and time of passage. In addition to recording passing objects, the counter also measures the temperature of the water every three hours.
After the scanner unit is the photo tunnel where a camera is placed. When a fish passes the counter, a short video sequence is recorded. The videos provide good opportunities to study the individual fish in detail. The video sequences not only allow fish to be identified to species with great certainty but also to be studied in detail such as sex, degree of spawning maturity, state of health and external marks such as a cut adipose fin (indicating that the fish is farmed) or possible damage from fishing gear or predators.
There is also a fish counter of the same type in the northern fishway, but this does not have a camera, so it is not possible to distinguish species or other characteristics.
Please note that the fish count data presented online during the season is preliminary and uninterpreted data. Some adjustments may be made after end-of-season review.
Salmon Observatory
The Salmon Observatory is located in Fällfors by the Byske River. The salmon observatory is an underground room where you can look out through large windows into one of the fishways. With a bit of luck, you can see salmon and trout passing through on their way up to the spawning grounds. Through monitors on the walls, you can also see them passing through the southern fishway that is directly adjacent on the other side of the river. The salmon observatory opens in June and closes at the end of September. It is free to visit the salmon observatory.
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