Science in the Bush: Lake Victoria

With my research permit finally in hand, I booked a flight to Mwanza on the southern shore of Lake Victoria to join up with a graduate student I met at the University of Dar es Salaam that’s doing research complimentary to what I’m hoping to do. All the delays meant that I was able to make it out to the lake just in time for her last two days of data collection. Not what she and I had planned but at least enough for me to scope out the site and make a plan for next time. Mwanza is Tanzania’s 2nd largest city and the setting of a documentary film called Darwin’s Nightmare about the social impacts of the overseas exportation of Lake Victoria’s massive and nonnative Nile Perch and how it provides a cover for the illegal smuggling of weapons into Africa. My expectations for Mwanza were based on this film (which I highly recommend to all you Netflixers out there) and to put it plainly, I was a bit scarred to be venturing there on my own. In Darwin’s Nightmare, Mwanza was a helacious place filled with poverty, prostitutes and homeless street children. My fears weren’t assuaged when I asked Baraka, the student I was meeting, if she could book me a room where she was staying. Her response was “I don’t think it would be good for you to stay where I’m staying. It would be safer for you to stay in town.” Ummm…ok. So I booked myself a room at the Christmas Tree Hotel and hoped for the best. I headed to the airport the next day for my first AirTanzania flight. I’m told they usually run about 5 hours late which would have put me into Mwanza at midnight. Not good. Luckily we boarded on time and the only weird thing was that you had to stop and pickout your bags from the pile of checked bags strewn on the runway and put them on a cart to be loaded on the plane yourself. Apparently the baggage tags that clearly say MWZ for Mwanza are just decorations. Baggage retrieval on the other end was even more sketchy. The plane was a full (and surprisingly nice) 737 which must seat about 200 people. Baggage claim in Mwanza was a tiny room with 3 one meter square openings in the concrete wall which dudes shoved everyone’s bags through. It was pretty much mass chaos. After a few minutes in the baggage mosh pit, I decided a better strategy was to wait by the door and make sure no one was taking off with my bag. When the dust settled (literally), I got my bag and braced myself for Mwanza. Before we reached the city I got my first glimpse of Lake Victoria. I could immediately see why the British named it for their queen. Sparkling blue water as far as the eye can see with a lakeshore of rolling green hills covered by huge, round granite boulders stacked awkwardly on top of each other (kind of like Joshua Tree for those that have been). Then we crossed the bridge and entered the town. My first thought was am I still in Tanzania? Mwanza was perfect. Nicely paved roads with curbs and sidewalks! Brightly painted buildings, traffic circles and everyone calm driving following basic traffic laws, and no litter! This place is a well kept secret.

The next morning I headed down to the research station to go out on the lake. We loaded up gear into a long wooden boat with an outboard engine and cruised down Mwanza Gulf to Baraka’s field site near the mouth of the Isanga River. It was breathtaking- miles of virtually untouched hilly shoreline covered in these awesome rock formations. Unfortunately, I didn’t have my camera because I couldn’t risk getting it wet (which I would have for sure). Baraka is studying how nearshore plants filter and alter the quality of the water entering the lake from the river and the watershed. One of these plants is water hyacinth, which is native to South America and invasive in Lake Victoria. In the late 1990s, this plant, which grows in these huge floating mats, was choking almost all the bays and nearshore areas of the lake causing major problems with on-lake transportation, fishing, water in-takes, etc. It declined through the early 2000s and is now rebounding. My interest is in the affect of these plants on water flow into the lake. We got to the bay into which the river flows to find that a huge, island-sized mat of water hyacinth, papyrus and reeds growing 2 meters tall had floated across and completely blocked the entrance sometime in the last 2 days since Baraka was last there. We cruised to a tiny lakeside village where people probably subsist mostly by fishing and only access to the rest of the world via the lake and hired 3 dudes with machetes. We took them back to the site and they climbed up onto the mat and started hacking away at the plants to make a passage for our boat. Imagine cutting down shrubs with a machete while standing on air mattress that you float on in a swimming pool that’s covered with broken tree branches. When they got a chunk loose, they tied it up and we dragged it away with the boat. It took hours just to cut it down enough so that we could push and pull the boat across the top of the vegetation for 20 feet to the channel of open water on the other side of the mat. It was arduous work and these guys all cut up and soaking wet. We collected the samples, saw a baby crocodile and headed back out through the path to find another island of vegetation was closing up the bay further out. There was only a boat width left for us to pass through and just after we crossed out to the open water we watched this “island” move across and seal off the bay. If we had taken 2 minutes longer, they would have had to hack a path through this island too. Insane. We dropped the guys off at their village and stopped along the way back to research station to buy fresh Nile tilapia from local fisherman who were in some cases out fishing on nothing more than a few tree branches tied together with vines just big enough to sit on and only partially floating in this lake where there are massive Nile crocs. We arrived back at the research station just as the sun was starting to set. It was a great great day!!