The fish-monitoring device we ordered from Oulu-based Simsonar Oy was positioned in the main bed of the Loukinen river in mid-August. Installation of this device is one of the steps we are taking to monitor the migration of fish in the stream in line with the requirements of our new environmental permit. Such monitoring measures were requested also by local residents and Kittilä’s environmental authority during the permit process.
The UVC system developed by Simsonar Oy is based on ultrasound technology. It is similar to the technology used in boats’ sonar. While a ship’s sonar system sweeps the area with a single beam, the fish-monitoring device generates an image from segments produced from 96 beams, which open at specific angles both horizontally and vertically. This enables the system to create a clearer image of the fish swimming past the device across the width of the river.
The device offers information on the number, size, and speed of the fish while also recording the detection time and the distance between the fish and the device. Though the system cannot be used to identify individual fish species, it has been established that migrating fish tend to swim straight past such a device while local ones crisscross the river in search of food.
The ultrasound “pings” transmitted by the system do not harm the fish or restrict the waterway’s use for other purposes. All the energy required by the system is generated via a solar panel and a fuel cell, for a silent, odorless, and environmentally friendly solution.
Once a day, the system automatically generates a report on the observations, which will be verified at the end of the monitoring season. These automatic reports can be used for day-to-day comparisons. The first-monitoring period ends in early winter when the river freezes. After this, a verified report on the fish in the river can be created.