Ocean Research Yields New Tools to Protect Lakes

Last summer, Senior Research Scientist Peter Countway and his family took a vacation to New Hampshire. He stopped by a friend’s house on Lake Winnipesaukee, walked onto the dock — and immediately recognized that potentially toxic cyanobacteria were blooming in the lake.

A dedicated scientist even while on vacation, Countway donned snorkeling gear and jumped in to collect a sample and shoot a video of the copious Gloeotrichia colonies discoloring the water.

Later that day, he uploaded the video to YouTube. Within 48 hours, the state had issued a precautionary warning about the bloom in Lake Winnipesaukee. Over the next six months, the local town began discussions about how to mitigate future blooms.

"Capturing a video provided the compelling evidence that was needed to get a conversation started about ways blooms could be prevented or mitigated,” Countway said. "The peak bloom of Gloeotrichia only lasts a few days, so it's easy to miss and hard to address.”

Gloeotrichia form dense colonies — they can contain as many as five thousand cells — that look like miniature dandelions gone to seed. Traditionally, a scientist trying to assess the magnitude of a bloom must undertake the arduous task of counting individual colonies in a water sample. However, the number of cells in these colonies can vary widely, and the result is not exact.

Inspired by the need for a more quantitative approach, Countway collaborated with Colby College professors Denise Bruesewitz and Whitney King and several of their students. The group developed a molecular method to estimate the number of Gloeotrichia cells in a water sample. Bruesewitz and King run a long-term monitoring program in the Belgrade Lakes in central Maine, working with students to comprehensively sample these lakes and test for harmful species. The researchers have used their new approach to confirm the presence of Gloeotrichia in several lakes, and they believe that this technique could improve efforts to monitor harmful algae and bacteria in many freshwater ecosystems.

"This technique is so sensitive that it allows us to detect even small numbers of cells, which would let resource managers see a bloom coming and take necessary precautions,” Countway said. "People living near lakes take water quality seriously, and we think this method could help reduce the impact of cyanobacterial blooms on their lives.”

Certain cyanobacteria including Gloeotrichia produce potent neurotoxins, some of which also promote tumor formation. Even in Lake Winnipesaukee, Countway detected low levels of several toxins. More research is needed to confirm the source of these toxins as well as the levels at which they may become harmful. This information will help lakefront residents and resource managers make decisions about how to maintain good water quality.

This summer, Countway plans to begin screening additional lake samples for cyanobacterial toxins and the organisms that produce them. He will take advantage of Bigelow Laboratory’s high-precision toxin testing capabilities, and he also hopes to use immunology-based methods that can provide a quick check for the presence of toxins. In addition to measuring these compounds, Countway plans to use molecular methods including the new test for Gloeotrichia to identify the particular species of cyanobacteria that are contributing to toxin production in a number of lakes.

"Bigelow has a reputation for studying phytoplankton and cyanobacteria in the ocean, and the experience and technology we’ve developed is equally applicable to lakes and rivers,” Countway said. "This is an opportunity to build on the Laboratory’s expertise in marine algal toxins to solve another pressing water quality issue that could be impacting the health and activities of many people.”

In the future, Countway wants to expand this testing capacity even further by equipping citizen scientists to monitor water quality using genetic techniques. He hopes to train volunteer members of lake monitoring networks to collect and analyze samples using a portable, smartphone-enabled device that can detect the DNA from harmful cyanobacteria.

He is currently testing a device manufactured by Biomeme Inc. for this purpose. A citizen scientist using this device could go from collecting a water sample to looking at results in about an hour, which could revolutionize the way blooms are detected.

Countway envisions a distributed network of citizen scientists passing data to researchers and water resource managers, providing the nearly real-time snapshots of cyanobacterial populations that are needed to stay abreast of quickly-changing conditions. He also hopes to use the Biomeme device to ground-truth drone-based aerial surveys of regional lakes in collaboration with researchers at multiple New England colleges. This will allow the scientists to compare high-resolution imagery of blooms with the dominant types of cyanobacteria in lake water — potentially enabling managers to monitor blooms over much greater spatial scales than is currently possible.

"This technology can empower people to help protect the health of their lakes and communities,” Countway said. "People want to know what's going on in their backyards, and this approach could help them find out.”