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LIFE Connects have clear connections to science and one of our ongoing projects is with Marie Andersson, a student at Lund University. Her master thesis is about the freshwater pearl mussel and the glochidia’s choice of host fish. She performed fieldstudies in Vramsån, one of the lager tributaries to Helge å.

– Vramsån is truly an amazing place, with lovely nature all year around. When I was here during July the river-water crawfoot was in full bloom and damselflies were flying around the river. My favourite thing about Vramsån must be the common kingfisher and it always seems to be around during my visits to the river. Vramsån is not to forget in the winter and with a little luck you can spot the white-throated dipper singing or looking for insects. There is always something to see and experience around Vramsån! says Marie about the river she has studied.

On the question on why she did choose to study the freshwater pearl mussel She answers:

– A part of LIFE CONNECTS intends to improve the freshwater pearl mussel’s status in Vramsån and new parts of the river will be available for fish migration during the project. To maximize the reintroduction of the freshwater pearl mussel it is important to know and research the mussel’s choice of host fish. The larvae of the freshwater pearl mussel, called glochidia, parasitize on the gills of trout or salmon for a part of its life cycle before they can survive on their own burrowed in the river bed. In the summer of 2020, we started a research were both salmon and trout along with pregnant female mussels where placed in boxes at the river bed. After 15 days the fish were examined and the number of mussel larvae on their gills were counted. The number of glochidia per fish varied between 0 and 107. The result also showed that river pearl mussels in Vramsån preferred trout over salmon. The study will also be used to determine where the most suitable spots to reintroduce the freshwater pearl mussel in Vramsån is.


Marie hope that her research can contribute to the LIFE CONNECTS project and to strengthen the mussel population in Vramsån.

– To be part of a big project like LIFE Connects is very exciting and I think it is important that my work and results will be used to save the freshwater pearl mussel in Vramsån by planning suitable actions. The mussels are so important for the ecosystem and filtrate the water for a better water quality. This leads to a better habitat for themselves and also for many other aquatic species, where mussels thrive many other organisms also do! she says.

After the thesis have been published in January Marie hopes to find a job where she can contimuing working with helping aquatic organism and improve aquatic ecosystems.


The LIFE CONNECTS project thank Marie for her persistent and great work! Through her efforts the project can create better living conditions and habitats for the freshwater pearl mussel in Vramsån. Good luck Marie and you are always welcome back to LIFE CONNECTS!