How can a small flatfish in Saanich Inlet help us understand the destabilization of an ecosystem in northern Europe? A new publication from VENUS research draws an unlikely connection between two distal coastal seas. Timor Katz is a PhD student at The Hebrew University of Jerusalem working with collaborators in Israel, Canada and the US to examine what happens when the “slender sole” flaps around in Saanich Inlet sediments. When groundfish resuspend sediment into the water during burying or feeding, dissolved silica is released – they measured three times the amount of silica in sediment clouds compared to clear bottom water. The inspired leap made by Timor, however, was to look at what happened elsewhere when groundfish stocks were destroyed by overfishing. In the Baltic Sea, cod – a bottom forager – were nearly eliminated in the mid 1980s. Coincidentally, diatom production diminished by 25%. Katz et al, (in press) propose that the loss of cod greatly reduced the amount of dissolved silica available for diatoms to construct their cell walls. Neither cod nor diatom populations have yet recovered.
This work has several implications, including: i) that ecosystems have complex connections in which perturbations have unpredictable consequences, and ii) research on VENUS in a coastal basin can have broad application in other parts of the world.
