Citizen Science

Help Solve a Problem on Africa’s Deepest Lake

September 7, 2017

Kakora Ramadhani poses on a fishing boat in the village of Buhingu on the shores of Lake Tanganyika. Photo © Ami Vitale

We have a problem in our project site on Lake Tanganyika in Tanzania.

Mahale Mountains National Park protects 250+ species of fish found nowhere else, including the world’s largest cichlid and Storm’s water cobra. Local fishers know that if they fish near the national park, they catch more fish. The problem is no one knows exactly where the protected waters of the park start.

Officially the line is 1 mile (1.6 km) offshore from the park, but there are no boundary markers because it is extremely difficult to demarcate the no-fishing area.

Problem Details

The national park’s protected waters cover 53,000 acres, and Lake Tanganyika drops to 3,300 feet (1,000 m) deep just offshore of the park in several places. This 400-mile-long lake has ocean-sized storms that can drag a buoy or snap a rope—which is itself a precious commodity in this remote part of Tanzania. What’s more, most fishing happens at night when it is hard to see a marker.

The lack of a clear boundary demarcation has created a lot of conflict between the park and local fishers. If fishers cross into park waters, they can lose their fishing gear or be hit with a fine by park rangers.

Fishermen use a net to pull in dagaa, a kind of sardine in the early morning light on Lake Tanganyika. Photo © Ami Vitale

Our Challenge to You

The Conservancy’s Africa team needs an innovative solution to this problem. To find it, we are applying a method that the business world is using increasingly often: a crowdsourcing competition.

We are encouraging people around the world to send us ideas for solving our demarcation problem. The solution could involve GPS-enabled mobile phones, super-tough buoys like the ones used on the North Sea, or a combination of tech and hardware. We are looking for something simple that we can try.

To engage the right audience of external “solvers,” we have partnered with the crowdsourcing specialists at SensisChallenges. But the challenge is open to anyone, including you!

Help us #DemarcatetheLake

Enter an idea in our challenge. Your idea could help create a lasting solution that can be replicated across many sites—one that benefits both people and nature.

The best ideas will win US $1,000 in prizes, and winners will get the chance to help us implement their ideas and make a difference to thousands of fishers on the world’s second largest lake.

For more, see the challenge website.

Craig Leisher

Craig Leisher is the Director of Monitoring and Evaluations for The Nature Conservancy’s Africa Region, where he leads science-based approaches to measuring people and nature impacts from conservation projects. More from Craig

Join the Discussion

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  1. Three points can be considered here
    – The park officials and fishermen should learn to a mutual understanding by GPS tech mapping as stated. With a proper meeting to study with digital tools.
    – The restricted or boundary area of the lake should be pillared with tall poles or signal tower, on both sides of banks to notice.
    – As the beautiful lake is large in length wise and short in breadth as seen in the map. Strong big sized bamboos should be joint in long and floated across the breadth of lake as to fishermen to avoid the crossing problem.

  2. Two lighthouses on each end of the boundary line,lined up on the line with the one nearest the shore the shorter of the two.

  3. What about a alarm that goes off when the fishermen cross the line. Something on the bouys like a flashing red light when a boat goes by.

  4. Considering that some fishermen cannot afford certain electronics and that storms catch above water buoys, try underwater buoys that emit light. The battery could be charged by water current or solar. Certain batteries are fairly long life and may need biweekly or monthly charge or changing.

  5. Give the fishers gps units that alarm when the boundary is near / hire patrollers.

  6. Find a native crawdad, and divert a certain portion of the water that feeds the lake to providing habitat for the crawdad. Shift the economy from tiny fish to tiny crustaceans…

  7. Good idea will tweet it cannot give permission for all my contacts but super tough illuminous buoys with a beep that indicates where the end of the area maybe useful. REpunk

  8. 1)We can use a pinging system to send location of the boat to the control room of the park and to the boat users. Preferably to their hand held devices. The distance between the disputed area and their last location so that if a fine is levied they can use it as proof to avoid it or claim it by both. 2)Self aligning buoy that can align itself to the distance( pre entered) using gps. So that it will not change. 3) Simple rope with floaters and reflectors attached with anchor can be used. 4) Making floaters high and big so that boats can’t cross over. 5) Installing boats with engine kill switches if they enter the restricted area( gps) and simultaneously send messages to the park authorities along with the location. 6) Incease patrol units. 7) Involve fishermen in park meetings and informing them of the need for protection and conservation.

  9. Use colorful soccer size balls with LED lidhts inside either tethered to each other or to rocks in the bottom

  10. Lasers is your answer, Could you give me a map of area with the demarcated area shown and the scale . Regards Daniel Becker ..