THE COMPLEMENTARY EFFECTS OF USING BOTH eDNA METABARCODING AND UNDERWATER VIDEO FOR MARINE FISH DIVERSITY MONITORING

Student: 
Sam Desmet
Room: 
room 1
session: 
Session 8, July 2, 16:00-18:00

With anthropogenic impacts threatening fisheries stocks and ecosystems, the need for effective fish diversity monitoring has never been higher. eDNA metabarcoding has proven to be a very sensitive and powerful tool for detecting the presence of species but comes with the limitation of not being able to provide population quality information. Remote Underwater Video on the other hand can provide information on relative abundances and behaviour of species, yet is prone to missing rare species and can have biases towards more mobile and distinctive species. As each method seems to cover the others weakness, the complementary benefits of using both methods in tandem were researched. The combination of both methods resulted in almost three times as many species detected than each method separately. The species overlap between the two methods was also quite low, which further shows their complementary benefits. Target marker selection during the metabarcoding workflow also seemed to majorly impact the species which could be detected using eDNA, as did the dilution which was necessary due to inhibition. With some refinements this method could be the ideal tool for routine fish diversity monitoring.