3. Watermelon snow in the field and under the microscope
During the 2016 field season we received over 50 reports of pink snow sightings in the backcountry of southwestern B.C. Some of these backcountry travellers submitted photos with their reports and a few brought us samples of the snow. First the sites, then the cells.
Sometimes the snow is only faintly pink. Other times, it is intensely red, as shown in the photo to the left. This “watermelon snow” is not only the colour of watermelon, but can also smell like watermelon.
How do algae colonize the snow every spring? Do they swim up from underlying substrate? Are they deposited by the wind? Do they fall as the nuclei of snow crystals? What conditions trigger the bloom? There may be many different answers to these questions.
Looking at samples of pink snow under the microscope revealed another level of beauty and raised many more questions.
From samples like those shown above, we have been able to isolate individual cells and encourage them to divide to generate a lab strain that we call “an isolate.” In a future post, I will show pictures of some of our new isolates of local snow algae and I will write about what we hope to learn from these cultures.
The images of field samples reveal the presence of not only algae, but also fungi, ciliates, and bacteria. It is likely that archaea and viruses are also present. How to these communities of diverse organisms work together to survive and thrive on snow and ice?
Follow the BC Snow Algae project at Snow Algae Reports.