This Summer, Help Us Sample Watermelon Snow for Science

Western Washington University's Dr. Robin Kodner is leading a citizen-science effort to better understand and document climate change through studying watermelon snow. Learn how you can get involved!
The Mountaineers The Mountaineers
April 29, 2019
This Summer, Help Us Sample Watermelon Snow for Science

We are excited to partner with Dr. Kodner and her students from Western Washington University for a third year on a citizen science project related to snow algae! This summer, take your alpine adventures to the next level and help us collect samples of summer "watermelon snow" algal blooms. These samples will support studies related to climate change and algal evolutionary biology.

If you participated in this project before, you know how easy it is to contribute, and how fun it is to be a part of this important research!

This isn't the first citizen science effort Mountaineers members have contributed to. In the past, our members have helped monitor invasive weeds and pika populations. Get involved this year, and you can make a difference by providing essential information for this important project.

How to Participate 

Step 1 

Pick up a sample kit at the Seattle Program Center, available starting end of May 2019. You can also sign up to receive a kit on Dr. Kodner's site here

Step 2 

Sample watermelon snow! Watch the video demonstration if you have any questions. 

Step 3

Mail the kit back to the lab. Your sample kit will include a pre-stamped envelope to make this process quick and easy. 

Note: Although sample kits will be made available starting at the end of May, due to snowfall we've received this spring the algal blooms may not show up until the end of June. 

Learn more about the project and field collection in our 2018 Q&A with Dr. Kodner:

Five Questions for Dr. Kodner


The Living Snow Project’s primary goal is to characterize snow microbiome biodiversity and distribution across the Cascades and other regional mountains over time.  We want to understand where snow algae bloom, how they disperse around the landscape, and how their communities evolve over time in response to climate-driven environmental changes. To do this, we need to collect lots (hundreds) of samples across from as many locations as possible over time to document communities from year to year.


So far, we have processed samples from 2013-2018. It looks like we have some new “species” of snow algae in the PNW – the strains we see here are genetically distinct from samples sequenced from Europe, Greenland, Japan, and Antarctica. We also see that each community (the algae + bacteria, fungi, and other amoeba-like things) in a region are different. For example, we have a number of samples from different elevations collected around Glacier Peak, and they contain different sets of algae species.  With more samples, we will be able to understand how random this variability is.


The Mountaineers have such a strong history of getting folks into the mountains and building a community who value education and stewardship. So, I see this as a wonderful opportunity to both educate many people about snow microbiomes and how important they are on a landscape scale and also engage them in the process of doing science. My goals for studying snow microbe communities are ambitious and I cannot do this kind of research without the help of our alpine recreation community. Ultimately, I want participants to feel like we are all part of a big team working to study our precious alpine snow and glaciers. 


Volunteers who sign up will get a collection kit. Each kit has two sample collection tubes, two gloves, and some plastic sealing film. We want people to bring the kits out with them on their adventures, and grab a sample of pink snow if they see it. The tubes have a DNA preservative in it (non-toxic) and people can scoop pink snow into the tube with the cap while wearing a glove. We typically want the brightest pink snow, so we ask people to look around and sample a spot that looks bright and clean. If there are lots of snow algae where the collector is hiking or climbing, we want them to just pick a convenient (or scenic) spot.

We are also creating a phone app this year where people can upload their sample tube number and GIS coordinates while taking the sample.  They can also share pictures of the sample in the app. In addition, we would love to have people share photos of the people doing the collecting and post them to social media use the hashtag #livingsnow and/or a hashtag of the watermelon and the snowflake icons (we show this on our website and Instagram account @living_snow_project) and tag @living_snow_project. This is a fun way for all everyone to see the cool places people are sampling. I think it will be fun to have a big regional community of people collecting.


No! Kits are small and light. As a climber myself - I know how important it is to keep them small, light, and easy to use. Just ask my climbing partners how many times I have asked them to wait for me on a glacier at 5 am while I'm scooping snow into a tube! To make them happy I have figured out how to make the process easy. It only takes 5 minutes with two sets of hands and a few minutes more with only one set of hands.

If you do not have a smartphone, you can just collect the sample without recording it on the app and carefully record all information on the sample tube.  We made a video that shows you how to scoop snow using the lid of the cap.  

Is it true that eating watermelon snow will make you sick? 

There is lore that watermelon snow will make you sick. I personally haven’t eaten any – but I know too much about microbes to want to eat it! My climbing partners tease me because I am the only one who doesn’t like drinking straight out of a glacial stream. I always say, “There are so many flagellates in there!” and they say, “yummmmm, flagella!”.  Back to the question – the algae themselves are not toxic and shouldn’t make you sick. There are many other fungi, bacteria, amoebas, and other tiny creatures that could give you some intestinal issues. A group of scientists at the University of Nevada Medical School published a study in 1997 comparing stool samples of people who ate pink snow, and those who ate white snow, and they did not find any differences.

Why does watermelon snow smell like …. Melon? 

I don't think anyone knows actually! There are not any published studies that I now of that have tried to characterize the compounds that smell like watermelon. Our observations suggest that it’s more common in slushy snow because we have smelled it sometimes, and not other times. These algae produce all kids of organic compounds that help them live in cold high light environments, so I bet it has something to do with that.

If watermelon snow is contributing to glacial recession, should we think about getting rid of watermelon snow altogether?

No! Watermelon snow is an integral part of snowy ecosystems. They are the primary producers of their habitat, so if we were to try to eradicate snow algae, all the other critters, like snow worms and snow insects would suffer. I think the better question is to ask are we spreading snow algae around when we walk or ski over  it and then continue up to an algae-free part of a glacier. I think we may be able to learn if that is happening from the data we collect through The Living Snow Project. If we learn that people are an important factor in spreading snow algae, then in the future we may consider cleaning our boots and skis after tromping though pink snow, especially when visiting sensitive glaciers. I wouldn’t worry about it now though. Let’s see what the data shows.