Bloom forming and toxic phytoplankton species in the outer part of Bilbao estuary.
Supervisors: Sergio Seoane, Jone Bilbao (UPV/EHU)
Phytoplankton play a crucial role in global geochemical cycles and provide essential ecosystem services. However, they can also cause significant problems through harmful algal blooms (HABs), which makes their monitoring vital for maintaining aquatic ecosystem health. This study investigates the phytoplankton community in the Port of Bilbao, using an innovative chemotaxonomic tool called PIGMENTUM. Unlike traditional methods that classify phytoplankton based on algal groups, PIGMENTUM categorizes them by pigment groups, avoiding the conflict in diagnostic pigments not having specificity. Complementary microscopy was employed to identify specific HAB-forming species that could be missed by pigment analysis alone. Our findings reveal that the phytoplankton community in the Port of Bilbao is primarily dominated by pigments corresponding to the groups FCA, CbCA, and ACA, with a shift towards HCA and CbCA in the summer. We also identified potentially harmful species such as Pseudo-nitzschia spp., Dinophysis spp., and Heterosigma akashiwo. These species pose a risk of being exported to surrounding waters via ballast water, potentially leading to HAB outbreaks. This research contributes to the understanding of phytoplankton community composition in the Bilbao Estuary and updates the records of HAB-forming species in the region.