What is acoustic telemetry?
Tools of the trade
Acoustic telemetry is a tool commonly used to study movements, behavior, migration and survival of aquatic animals. Acoustic transmitters emit an ultrasonic ping that is decoded by receivers when the tag is in range. Knowing the location of the receivers can allow us to infer the position of the animal because the receivers record the date and time of the detection, along with other information such as the temperature, speed, or depth that the detection came from. We capture animals with approval from local authorities and animal welfare institutions and insert tags following training and guidelines for best practices, some of which we have helped to develop for the field. Animals are robust to this surgery and give good data about where, when, and how they move.
Network of receivers
The Bergen Telemetry Network is an array of acoustic receivers in and around the fjords of Bergen in Western Norway. The area is an ecologically important zone for Atlantic salmon and sea trout and the network overlaps with the UNESCO cultural site in the Osterfjord. Our receivers are TBR800, TBR 700 and 700L models from Thelma Biotelemetry. The receivers are often moored to concrete anchors that hold them in place for detecting fish. Some of these anchors are serviced by snorkeling. Fish are tagged with acoustic transmitters and their detections in marine, fjord, estuary, river, and lake habitats allow us to recreate their movements and understand how they interact with their environment. Our research program specifically investigates how fish are affected by stressors such as climate change, disease, hydropower, and urbanization and leverages this acoustic array to understand the ecology of trout, salmon, wrasse, and potentially more species in the future.
We do not simply tag and track animals haphazardly, but take time to consider the questions and consult with local stakeholders, managers, and industries about what the knowledge needs are. Our team includes world leaders in aquatic experts and future leaders in the field from the University of Bergen and we report on our findings in peer reviewed scientific journals to share the knowledge that we generate with the world. Our articles are available on Google Scholar and are linked here as well. The telemetry data are archived on the Ocean Tracking Network database for future generations to use and reveal how aquatic ecosystems may change in the future as tracking efforts go on.
Our research leverages the availability of the receivers in the Bergen Telemetry Network to track fish and other animals and provide advice to industry and management about how to best manage the resources and solve pressing problems as fish and other species are increasingly imperiled by human activities.