As I've mentioned before, Lac de Guiers is a long skinny lake that flows from the Senegal River, whose water levels used to seasonally fluctuate before dams were installed at its northern and southern ends in the 1970's. Lac de Guiers is the drinking water supply for Dakar and is also used for sugar cane fields at the north end of the lake, so now the water is kept high year round, which has changed the system dramatically for both humans and wildlife. Niaga told me that before the lake was dammed, in 1972 he remembers a severe drought that almost dried up the entire lake. Lots of dead manatees were seen and eventually the sugar cane company dug a channel to the southern end of the lake to get water for their fields. Manatees also used the channel to escape back to the Senegal River.
Now that the water is always high, it has flooded areas around the lake that used to be dry. One known impact is that it has reduced the nesting habitat for the endemic Adanson's mud turtle (this is the only place it occurs in Senegal) which my husband Tomas has been studying here for many years. As we drove down the eastern shore of the lake, the first village we stopped at was Temey. Here we saw dead trees at the waterline that died as a result of flooding. It reminded me of dead trees we also saw in Ghana as a result of damming to create Lake Volta. The lake is so wide here you can't see the opposite shore.
Each village we stopped at had a separate area where fishermen live, so we went to those areas to talk about manatees. At one village the chief admitted that they eat manatees when they are incidentally caught in fishing nets, and they had also found a naturally dead carcass near the village a few months ago (unfortunately they said it was not still there). Niaga (below on right) spoke to the villagers about their community-based conservation initiative at Tooc Tocc Reserve and the importance of protecting manatees to the ecosystem. People really responded positively when they heard Niaga because he's from the lake and understands their lives.