WWU researcher continues watermelon snow project

BELLINGHAM – Mount Baker and the surrounding North Cascades are known for their white-capped peaks and blue-toned glaciers, but there’s a lesser-known hue also found in the high-elevation snow.

Algae can cast a light pink tint across large swaths of snow or form pinkish-red pockets and pools as the snow melts, making for a colorful display called watermelon snow.

A research project inspired by watermelon snow on Glacier Peak in the North Cascades southeast of Darrington is now in its sixth year, and in that time it has grown substantially.

Western Washington University biology professor Robin Kodner, who is leading “The Living Snow Project,” shared updates about the research Wednesday as part of the university’s annual “Science and the UniverCity” lecture series that is free and open to the public.

“This is a pretty common phenomenon,” Kodner said after a few in the audience raised their hands to indicate having seen watermelon snow.

The challenge in finding watermelon snow is getting to high-elevation areas where snow algae is found. That’s why the project relies heavily on those who recreate in snowy mountain terrain to collect samples when they come across pink snow.

Kodner, students and volunteers collect samples during the spring and summer months, when the algae is present.

Those samples are then processed in a lab at the university’s Shannon Point Marine Center in Anacortes, where students involved with the project extract DNA from the microscopic organisms in the snow and sequence it to identify the variety of species present.

Kodner and students helping with the project also sometimes look at samples through field microscopes while in the mountains. Kodner showed images of some magnified snow algae Wednesday.

Some of the tiny organisms that are invisible to the naked eye look like the red buttons associated with blood cells. Others look like prickly green balls.

Those algae can make snow appear a light pink or deep red.

“There was so much snow algae in this case that we had actual pools, red pools,” Kodner said while showing a photo from a sample site at Glacier Peak.

A growing effort

Since the project began in 2013, the number of volunteers collecting samples has grown from fewer than 10 to 185.

The number of samples has also grown, with five times as many samples collected in 2017 than in the previous four years combined.

Kodner said she set the goal of obtaining 500 samples this year compared to the 210 collected last year.

The reach of the project has also expanded outside of the North Cascades.

With the help of Northwest Avalanche Center volunteers, the project now has data from sites throughout the Cascade Range in Washington and Oregon. The project has also received some samples from Peru.

“We’re ramping up each year,” Kodner said.

Throughout the Cascade Range, samples will be collected until the first new snow falls, which is usually in late September.

Kodner is encouraging hikers, climbers, skiers and others who spend time in the snowy elevations of the North Cascades to join the growing volunteer effort.

“Whenever you can see pink snow, we want samples,” she said.

Sample collection kits are available at locations in Bellingham and Seattle, and can be requested by mail.

When volunteers see pink snow, they scoop a sample into a tube, seal it and mail it to Kodner’s research team. That team has included dozens of university students over the years.

“There’s a whole army of Western students that have participated in this research,” Kodner said.

Kodner was inspired to start the project after discovering snow and pools of water tinted pink and red while on a climbing trip at Glacier Peak.

She said she was captivated by the sight.

Involved at the time in marine research focused on algae and bacteria, Kodner said she became curious about the microscopic organisms responsible for watermelon snow. When she could find no research about the genetics or evolution of the organisms in the North Cascades, she decided to start some research at Western.

Several discoveries

The research has revealed several types of algae found in watermelon snow.

Kodner said samples from the North Cascades have had more types of algae than samples from other areas. It’s common, though, for one type of algae to be most prevalent in each sample, she said

The research has also shown that in Washington’s North Cascades, watermelon snow has three common groupings of algae. At least one of those groupings is also found in areas of Oregon and even Peru.

“What we’re learning is that samples from really far away from each other can be really similar,” Kodner said.

As the DNA of the snow algae has been sequenced in the lab, Kodner said project researchers have also found some unknown species.

“Some of these don’t even have names yet,” she said.

In some of the samples, the researchers have found other microscopic organisms larger than the algae, suggesting they could be creatures that eat snow algae.

Many more questions

How those microscopic organisms and the snow algae fit together in a food web is among the many questions Kodner said she hopes to answer.

Long-term, she said she hopes the research will reveal how climate change will affect the DNA of snow algae, how snow algae could affect snow and glacier melt as the global climate warms, and how snow algae moves from one location to another.

Before those questions can be answered, the researchers need to know what types of algae and bacteria are found in watermelon snow and how they interact – questions they are well on the way to answering, Kodner said.

Meanwhile, researchers in other regions have found that the snow algae that causes watermelon snow can make snow and ice melt faster, including in the Arctic and Alaska, according to studies released in 2016 and 2017.

Kodner said that raises additional questions The Living Snow Project could answer, such as what impact watermelon snow could have on the already melting North Cascades glaciers.

Volunteers have also raised questions Kodner would like to eventually answer, such as whether hikers and skiers could be moving snow algae from one location to another on unwashed boots or skis.

“We should be able to sort of disentangle those impacts because we have so much data,” Kodner said.

To pursue answers to more of those questions, Kodner is making plans to expand the effort to gather data.