After spending our first two days setting up the newly renovated lab and recovering from jet lag we sprung into action, making a number of trips out to Station 1, processing water samples and setting up experiments in the lab.
There is an intense bloom of what we think is Gymnodinium going on in the nearshore and at Station 1: as soon as the ice cover is broken yellowish-brown water with a characteristic “fishy” dinoflagellate smell gushes up. Yesterday secchi depth (a measure of water clarity) at Station 1 was only 7 meters, unusually low for open Baikal, and chlorophyll values measured with our YSI sonde got as high as 8.5 µg/L! Aside from Gymnodinium we see plenty of the diatoms Aulacoseira and Synedra in phytoplankton net tows.
Paul has been working with the water we collected at Station 1, filtering samples for meta-genomic and nutrient analyses, and isolating algae from phytoplankton net tows. In the meantime Kirill and I have set up a temperature tolerance experiment with Epischura baikalensis, the dominant Baikal zooplankter. Preliminary results show that winter Epischura is surprisingly tolerant of high temperatures. In fact, so far, there seems to be almost no difference between summer and winter Epischura in their ability to tolerate warm temperatures! Today we started an experiment to measure the feeding rate of Epischura. Epischura is a notoriously picky eater, so hopefully the method we’ve been developing this winter with American copepods will work for Epischura.
If the warm weather (very relatively speaking) holds for the next couple days we plan to begin our spatial survey of the distribution of algae under the thick and clear ice of Lake Baikal. It will be very interesting to see how winter algae respond to variation in snow cover, ice thickness and water depth.