My name is Anita Laborde, I graduated as a civil engineer in 2015 and I obtained my MSc degree by January 2016 at the University of Concepción, Chile. My study area is ecohydraulics. I’m particularly interested in understanding and alleviating the impacts of anthropogenically constructed structures in rivers and their effects on the environment. That motivated me to enrol in the PhD program on Environmental Sciences at the University of Concepción. Here my PhD research focuses on the development of sustainable technologies to improve river connectivity.
University of Concepción is part of a scientific exchange project with the title “KEEPFISH: Knowledge Exchange for Efficient Passage of Fish in the Southern Hemisphere”. As part of my PhD and the KEEPFISH project, I am currently doing internships in three northern hemisphere universities, Technical University of Denmark, University of Magdeburg and University of Southampton. I just finished my first internship at the Technical University of Denmark (DTU), and I would like to share with you part of the experience.
My first experience relates to differences in the environments. The rivers in Denmark are generally small, the majority less than 10 m wide and flow rates less than 10 m3 s-1 and relatively species poor. The specific river I worked in was even smaller, less than 4 m wide. In Chile, many rivers are much larger. Fieldwork in Chile is carried out in river widths often around 100 m and higher discharges. The focus in Denmark is on economically important species such as eel, salmon and trout aimed at understanding (and alleviating) limiting factors. These species grow relatively big (adult size of 40 – 100 cm), whereas the focus species in Chile has an adult size of about 15 cm. These differences highlight that the choice of an appropriate study method is very important for successful outcome of a given project.
During my internship, I have learned about multiple technologies available to study fish behaviour. Specifically I gained experience with electrofishing and trapping of trout (wolf trap) as well as various methods of both conventional tagging and tagging with electronic tags (Telemetry). The electrofishing technique and the tools used are the same in both countries, with the difference that the shape of the river facilitates the individual’s localisation. Catching fish in a wolf trap is a very old and very efficient methodology that potentially allows capture of all the fish passing through a specific section of the stream. It was very interesting to see it implemented and running.
About tagging, I learned a lot, especially about using telemetry. The technology is known in Chile, but not widely used as in Denmark. I was involved in a study investigating the effect of a millpond on activity of migratory juvenile trout (smolts) using passive integrated transponder (PIT) technology. The small size of the river enables the deployment of PIT antennae’s both above and below the mill pond detecting passing fish. A number of smolts are electrofished and PIT tagged every year and their subsequent behaviour monitored by the antennas. Smolts have been tagged in 2012 and 2013, when the Millpond was present and again in 2015 and 2016, after a bypass was constructed around the Millpond.
Feel free to contact me with any questions or interest in the experience (firstname.lastname@example.org).
Anita \\ Silkeborg, Denmark
KEEPFISH is funded by the European Commission through the Marie Sklodowska-Curie action, Research Innovation Staff Exchange (RISE-2015-690857-KEEPFISH). For more information about the project see www.coventry.ac.uk/research/research-directories/current-projects/2015/keepfish/.