In the bloom...almost
Cyanobacterial blooms during the summer are reoccurring phenomena in the Baltic Sea. This summer we have already encountered the two main species responsible the blooms, Aphanizomenon sp. and the toxin producing Nodularia spumigena (see previous posts), but so far not in the abundance that would qualify as a bloom. With the help from our colleagues back at JCVI in La Jolla and the Swedish meteorological institute’s satellite tracking of algae blooms (www.smhi.se) we have been following the development and waiting for the bloom to show up. However, we are approaching the end of our Baltic Sea journey and due to the relatively cold and windy weather blooms have been moderate this year. We had almost given up on the chance of encountering a bloom and due to the clouds the satellite imagery wasn’t much help when…. Finally, a bloom! Well…almost a bloom… On our way to Kalmar, just on the southern tip of the large Öland Island we spotted a lighter streak in the water and when taking a closer look we could see that the water was filled with small whitish aggregates of some sort. In the microscope we could confirm that these aggregates were indeed cyanobacteria and Nodularia spumigena seemed to be dominating the sample. Due to the whitish colour we suspect that the filaments were dying since these types of blooms are typically more yellow in color.
After sampling we continued to Kalmar, where Professor Åke Hagström was waiting for us on the dock together with his son. I was also happy to see my own brother Anders there to greet us. He and his family are in Öland where he is visiting my parents in their summer house. It was great seeing some familiar faces!
The next morning Åke came back together with his colleague Dr. Lasse Rieman for breakfast and a tour of the boat. Jeff and Åke exchanged fascinating experiences from air sampling of microbes and Åke told us about his new appointment as head of the Swedish Institute for the Marine Environment, an exciting initiative aiming to coordinate the efforts of all four Swedish marine research centres, read more about it here.