ADVENTURES AT LAKE KIVU

Lake Kivu--Michael

We spent last week at Kivu Lake.  It’s a 2.5 hour drive from Kigali through hilly eastern Rwanda.  Dad had to meet a World Bank team at the beginning of the week at a hotel in Kibuye.  We came early and spent part of the weekend with him before he took off with the team to check on projects elsewhere in Rwanda.

Lake Kivu spreads across 60mi of Rwanda’s eastern border with the Congo.  It 875 sq. mi and over 1500 ft. deep, making it one of the 20 deepest, most voluminous lakes in the world.  Kibuye is one of three main towns on the lake (including Gisenyi, Cyangugu and Kibuye…look them up!).  The town is the main city of Karongi District. Compared with Kigali, Kibuye is very small and relaxed; its schedule centered around fishing. 

Walking around Kibuye and fishing communities we did not get nearly as many stares and cries of “Mazungu!” as we do in Kigali.  Most of the people we met were kind, gracious and helpful.  Two boys who spoke a small amount of English helped us find a boat to explore the islands and some fishermen showed us how they mended their nets.

While we were there we swam, walked, explored islands, boated and relaxed.  We saw millions of bats, learned how fishermen mend their nets, and met the Olympic swimmer of Rwanda and saw swimming cows.  

CO₂ in Kivu

While reading about Rwanda’s geography I learned about a unique buildup of carbon dioxide in the waters of Kivu Lake caused by the nearby chain of  active volcanoes.  Large amounts of CO₂ saturated in the water can cause a limnic eruption when the CO₂ suddenly rushes to the surface of the lake—like the fizzing of a soda can but on a much larger scale.   The CO₂ gas settles in a cloud just above the lake, suffocating the inhabitants around the lake. 

As soda pop is stored in a pressurized bottle or can to keep the Co₂ dissolved, so its the same at the bottom of the lake --water pressure is high and alot carbon can be saturated.  When the carbon becomes supersaturated, a disturbance, like the activity of a volcano, can cause some of the dissolved CO₂ to separate from the water and rise to the surface (like when you pull the tab of a soda can).  The rush of CO₂ brings up a current of water. As the water rises, the pressure drops and more CO₂ separates from the water.  Consequently, the lake erupts as the CO₂ empties from the lake. 

This happened twice in 1960’s in two other lakes in Cameroon.  Because these lakes are deep and volcanic activity is nearby, the CO₂ slowly grew until it was released. It’s only possible in equatorial lake, so you don’t have to worry about Whiskytown or Shasta Lake blowing up (for those of you living in Redding Ca). 

There are over 100 million yds³ or 17 ½ billion gallons of CO₂ submerged in the lake.  Sounds like a lot, but experts say it’s not yet at dangerous levels of concentration. That doesn’t say much with an active range of volcanoes a few miles away which could easily trigger a release of the CO₂.  There are 2 million people living on Kivu’s shore. 

There is also a large amount of methane (85 billion yds³) at the bottom of Kivu; enough to power the US for a month or Rwanda, at its current energy consumption, for 400yrs!  The plan here is for the methane to be extracted from the lake and used to supply most of Rwanda’s electric needs in 2012.  That will replace the expensive wood burning that is currently being used. We were able to see the project site the construction had only just begun . 



Bats

at Napoleon Island        by Daniel!!!

Last week, we went to Lake Kivu, a huge lake, that borders the Congo west of Rwanda.  We met some Rwandan orphans who were part of a co-oporative that had little motorboats to take people around the lake.  So we paid them, and they took us to Napoleon Island (it is shaped like Napoleon’s hat).  When we arrived our guide took us to a forest where there were millions and millions of bats- actually our guide said that there were five or six million bats on that island.  When we were in the forest our guide clapped; so I clapped and clapped some more and hundreds of bats started to fly out of the trees next to me.  One of them decided to have some target practice on Nathan’s back-pack, so it let down a rapid fire of doodoo, and sure enough it hit square on target!!!! 

Bats are blind with eyes that are not useful.  Instead of sight, bats have a sonar system that detects anything around them.     A bat came fluttering to the ground two feet away from me; when I moved, it flew away.  One time our guide threw a rock at a swarm of bats and all of them dodged it, and dodged other bats!         

At times we could get up close and see some little baby bats clinging to their mothers chest as they flew around or hung up-side-down on a limb of a tree, all lined up. 

We saw some bats eating leaves and berries of the trees they were hanging on.  Monkeys are predators of bats, and there were monkeys on other islands, but there are no monkeys on Napoleon Island.  The only other animal that were on that island were cows that swam over from the mainland.                                                                                                                                   

We enjoyed the ride back to the mainland (and the guide let me drive the boat back!)

Lake Kivu Fishing--Nathan

  

Rwanda is a land locked country, so there are limited fishing grounds. Most all the fishing is in Lake Kivu, one of the Great Lakes of Africa (but very small compared to Victoria)

 Looking out the window of our room just on the water’s edge one evening, we watched the fishermen paddle their boats out towards their fishing spots.  Most of the boats were handmade wooden canoes made for 2 or 3 people, but some were very large and had long poles attached to the front and back to keep the nets away from the boat. The fishermen go out for the whole night, taking with them everything they need .  They set up their nets for the night; and lure the fish with a kerosene light or fire.   In the morning after sleeping in the boat, they pull up their nets and haul their catch into the boat.  Every morning we heard and saw them paddling back to shore, chanting the whole way. 

One morning we visited the fishermen where they came to shore to sell their fish.  It surprised us to find a nice building rather than a run down market place. Seemed to be a well funded project.  Ladies were selling fresh fish they bought from the fishermen; there were drying racks to spread out the fish, and there was a grinding machine to grind the dried fish into fish meal. 

Not far away in the same cove we visited some fishermen repairing their canoes and mending their nets.  I watched one wedge cloth into leaky cracks in the boat and another fixing a net with a spindle wound with a kite string type material.  We could not communicate but we could greet them in our simple vocabulary and tell them our names.  In the boat they had some pads to sleep on, repairing equipment, and some nets with cut flip flops for floats. 

And yes we have eaten some of these very fish, rolled in flour and fried in oil.