Changing Planet

New Research Buoy Installed on Lake Tanganyika

A new research buoy is lowered into Lake Tanganyika. (Photo by Bill Perry.)

An international research team partnering with a local fisheries research institute installed a research buoy in Tanzanian waters on Lake Tanganyika earlier this month. It is the first of its kind on the African continent, marking a major milestone in both local and global research to understand the role and response of lakes to climate change.

Installing a research buoy on Lake Tanganyika was the dream of Ismael Kimirei, director of the Tanzania Fisheries Research Institute (TAFIRI) research center in Kigoma, Tanzania, along with his research partner, Catherine O’Reilly, an associate professor at Illinois State University. O’Reilly has conducted research on climate change impacts on the lake and also recently led a Global Lake Temperature Collaboration study that shows how climate change is rapidly warming the world’s lakes. I spoke with O’Reilly via Skype while she was in Tanzania earlier this month and caught up with Kimirei via Zoom chat yesterday where he described the launch of the buoy on Lake Tanganyika as “the best day of my life so far.”

[Warming Lakes: Climate Change Threatens the Ecological Stability of Lake Tanganyika]

O’Reilly first began working with Kimirei when he was a graduate student at University of Dar es Salaam in Tanzania in the mid-2000s. As members of the Global Lake Ecological Observatory Network (GLEON), they began collaborating several years ago with Peter Staehr, a senior researcher at Aarhus University in Denmark. Staehr secured funding for a research buoy on Lake Tanganyika from DANIDA, Denmark’s foreign assistance program and now leads the CLEAT project, a collaboration among Aarhus University and TAFIRI, established in 1980 with one of four centers based in Kigoma, as well as the University of Dar es Salaam, Illinois State University, and Enavigo Consult in Denmark. O’Reilly participates in the project with additional funding from NASA.

Photo: CLEAT project on Lake Tanganyika. Credit: Bill Perry.
Catherine O’Reilly, Ismael Kimirei (second from right) and Peter Staehr review plans for positioning the anchors for the Lake Tanganyika CLEAT 01 research buoy with TAFIRI staff and the ship’s crew. (Photo by Bill Perry.)

The buoy was donated by the Danish Maritime Authority and comes from their inventory of ones that are rugged enough to withstand wintering over in Baltic Sea ice. Without access to a buoy tender, the research team found that positioning the buoy on one of the world’s deepest lakes in a developing African nation just south of the equator proved to be a challenge, to say the least.

Just moving and then loading the 400 kilogram (880 pound) buoy, its 400 kilogram (880 pound) counter weight, and two 500 kilogram (1,100 pound) anchors – each with 10 meters (33 feet) of chain requiring two strong people to move – was a major undertaking. The Tanganyika buoy, named “Cleat 01,” had to be moved by truck from its shipping container at the TAFIRI office in Kigoma to the port 1.5 kilometers (1 mile) away and then lifted into the water, tasks that required calling in a special crane, then a forklift, and involved lots of other creative problem-solving.

Photo: Deploying the CLEAT 01 research buoy in Lake Tanganyika. Credit: Bill Perry.
Lifting the CLEAT 01 research buoy and its anchors required calling in a special crane to the Kigoma port on Lake Tanganyika. (Photo by Bill Perry.)

For a relatively quiet fishing village on the shores of Lake Tanganyika, the installation of such a high tech piece of research equipment was a big deal. Two ships were involved, TAFIRI’s r/v Echo and the m/v Maman Benita, a commercial freighter, each with different roles. Many people showed up to watch the researchers work side-by-side with the crews of the Echo and Maman Benita while they maneuvered the heavy equipment into position. Once secured to the larger of the two ships, the buoy was towed to its new home. Communication between the two ships proved difficult at sea, complicating the installation, but at least the weather cooperated.

Photo: Installing the CLEAT 01 research buoy on Lake Tanganyika. Credit: Bill Perry.
The buoy was towed from Kigoma port to its current position on Lake Tanganyika. (Photo by Bill Perry.)

One of the most challenging tasks was putting the anchors in place, according to O’Reilly. “In retrospect, we know how we would do it now, but it was stressful at the time because we were just shooting in the dark to find the right location,” she said. The anchors needed to be in water that was deep enough for automated sensors to capture the larger scale dynamics of the lake, including the deep upwellings important for maintaining fishery health. The anchors couldn’t be placed in water that was too deep or they would run the risk of running out of cable to attach to the buoy.

“It all worked out,” said O’Reilly. The CLEAT 01 buoy ended up in 370 meters (1,214 feet) of water about 3 kilometers (2 miles) from the ‘Mzungu’ Beach and about 8 kilometers (5 miles) from the Kigoma port. The automated sensors attached to the buoy are now gathering weather and water quality data every minute, including water temperature and dissolved oxygen profiles to a depth of over 150 meters (500 feet) and 100 meters (330 feet) respectively.

Photo: CLEAT 01 research buoy on Lake Tanganyika. Credit: Bill Perry.
The CLEAT 01 research buoy on Lake Tanganyika is the first of its kind on the African continent. (Photo by Bill Perry.)

Bill Perry, associate professor at Illinois State University, was onsite to help install the buoy and made daily posts to his blog with great photos, documenting the historic event. He also worked with Rishi Saripalle, an assistant professor, and Jonathan Mitchell, an undergraduate student, both at ISU, to develop a web app to display the buoy data.

A few days after the sensors were installed, fisherman stopped by the TAFIRI research center in Kigoma to find out the wind speed on the lake because they were worried about an approaching storm. As has been found at other GLEON research sites, the buoy data has usefulness beyond research alone.

The CLEAT 01 buoy is the first lake observatory installed on the African continent as part of GLEON’s rapidly growing global network. It joins hundreds of other research buoys in lakes on seven continents, but its significance was not lost on those in attendance at the launch event in Kigoma. “When I showed the map of GLEON research sites with the addition of Lake Tanganyika at the launch event, the audience spontaneously erupted in cheers and applause,” said Staehr.

Photo: Group photo of the launch event for the Lake Tanganyika research buoy. Credit: Bill Perry.
Dignitaries, local officials and fisherman gathered at TAFIRI Kigoma Research Center to celebrate the launch of the Lake Tanganyika buoy with the research team. (Photo by Bill Perry courtesy of TAFIRI.)

The main goal of the project is to provide enough information for sustainable management of fisheries in the lake, according to O’Reilly. For this reason, the research team has placed a high priority on engaging with the fisherman early in the project, so when the time comes for making future management decisions, this key group will be involved. The high frequency buoy data will be used to calibrate three-dimensional models, also developed as part of the CLEAT project, and help researchers understand lake dynamics and predict how the lake will change under future climate scenarios.

The fisherman were especially proud to be a part of the launch event, according to Kimirei. “Lake Tanganyika’s fisheries are important to local people but changes in climate are disrupting the lake’s ecology,” he said. The research team is hoping that the CLEAT project will help them to better understand the respective roles of fish harvesting and climate change on the health of the fishery.

Photo: showing web app of lake buoy data to local fisherman. Credit: TAFIRI.
TAFIRI staff Huruma Mgana and Emmanuel Sweke show the local fisherman a web app that displays data from the Lake Tanganyika CLEAT 01 buoy. (Photo courtesy of TAFIRI.)

“This is a major milestone for GLEON and demonstrates how effective a grassroots scientific network can be,” said Kathleen C. Weathers, co-chair of GLEON, and G. Evelyn Hutchinson Chair in Ecology at the Cary Institute of Ecosystem Studies in Millbrook, NY. “Thanks to the hard work, creativity and tremendous collaboration among the CLEAT project partners, there is now a research buoy in one of the world’s biggest and oldest lakes, which also happens to be a first for the African continent.”

Another goal of the project is to train the next generation of lake scientists like Kimirei, O’Reilly and Staehr who dream big, have the ability to work as a team, and bring cutting edge science to the developing world.

Lisa Borre is a lake conservationist, writer and avid sailor. She co-founded LakeNet, a world lakes network that was active from 1998-2008. A native of the Great Lakes region, she served as coordinator of the Lake Champlain Basin Program in the 1990s. She is now a Senior Research Specialist at the Cary Institute of Ecosystem Studies and an active member of the Global Lake Ecological Observatory Network (GLEON). She is also co-author of The Black Sea, a sailing guide based on research conducted while circumnavigating the sea with her husband in 2010. 

Lisa Borre is a lake conservationist, writer and avid sailor. A native of the Great Lakes region, she served as coordinator of the Lake Champlain Basin Program in the 1990s and co-founded LakeNet, a world lakes network that was active from 1998-2008. She is now a Senior Research Specialist at the Cary Institute of Ecosystem Studies and an active member of the Global Lake Ecological Observatory Network (GLEON). She is also on the board of directors of the North American Lake Management Society (NALMS), the advisory council of the Lake Champlain Committee, and an associate investigator with the SAFER Project: Sensing the Americas' Freshwater Ecosystem Risk from Climate Change. She writes about global lake topics for National Geographic's Water Currents blog and speaks to local, regional and international groups about the impacts of climate change on lakes. With her husband, she wrote a sailing guide to the Black Sea based on their voyage there in 2010.
  • Betsy

    Inspiring article and photos enhanced the text.

  • cleophace gupta

    we need a big change in order to conserve our lakes

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