During week 24, colleagues from the Institute of Coastal Research and Institute of Freshwater Research met at Drottningholm to dissect eels together. The purpose of the meeting was to share experiences and go through the various steps in individual sampling and ensure that sampling is done in the same way regardless of who performs the dissection.
- In our work to evaluate and develop the monitoring program for eels, we noticed in 2023 that the individual sampling differed quite a lot depending on whether the eels were dissected by staff from the Institute of Coastal Research and the Institute of Freshwater Research. We therefore started work on coordinating the sampling in 2023 - a work that has resulted in the dissection meeting here at "Sölab", says Philip Jacobson, researcher at the unit for migratory fish at SLU Aqua.
During the dissection meeting, both yellow and white eels were dissected to jointly calibrate and synchronize the dissection of eels.
- It is important that we dissect the eels in the same way, regardless of which of our labs the eels are dissected at. We want to be able to use all the eels we sample in our analyses, Philip continues.
The greatest need for calibration was the measurement of eel eyes and fins which, in relation to eel length and weight, are used to calculate the eel's development phase. In addition, the method for counting the number of swim bladder parasites (Anguillicoloides crassus) and for how somatic weight should be sampled was also standardized.
- In 2023, we have also worked so that we can store the same type of individual data in the KUL and Sötebasen databases. The next step is to develop a department-wide dissection manual that shows how we dissect eels at SLU Aqua. The dissection manual is an important part of our ongoing work to quality assure and document what we do in the monitoring program for eels, Philip concludes.
Joint dissection of eels. Photo: Philip Jacobson.
SLU Aqua annually collects eel at sea, from the west, south and east coasts of Sweden, as well as from most lakes and rivers within the framework of DCF. If you have any questions about SLU Aqua's monitoring program for eel, do not hesitate to contact Josefin Sundin, Philip Jacobson or Per Holliland.
Josefin Sundin, Researcher
Department of Aquatic Resources, Institute of Freshwater Research, SLU
josefin.sundin@slu.se, +46 10 478 42 24
Per Holliland, Environmental Monitoring and Assessment Analyst
Department of Aquatic Resources, Institute of Coastal Research, SLU
per.holliland@slu.se, +46 10-478 41 33