Recent changes to the biogeochemistry of Muchalat Inlet, B.C., and the implications for HABs

Senior thesis written for Oceanography 445

[author abstract] The western coast of Vancouver Island, B.C. experienced anomalous events in the late spring and early summer of 2014. A persistent warm sea surface temperature anomaly reached the fjords, as did a massive “flushing” event, replenishing deep fjord basins with oxygenated water (Bond et al. 2014, Rick Keil personal communication). During this same period, a Harmful Algal Bloom (HAB) hit Muchalat Inlet, resulting in a large fish kill (Judd 2014). This study assessed the possibility that the recent HAB was instigated by toxin-producing phytoflagellate cysts that germinated due to the anomalous change in bottom-water conditions...This study concludes that recently deposited sediments exhibit a favorable environment for cyst germination. Based on these preliminary results, it seems plausible that toxin-producing cysts, which were capable of germinating under anomalously warm and oxic conditions, generated the 2014 HAB.

University of Washington School of Oceanography