Ten Days in Senegal

On February 9th we headed east from Dakar towards Matam, a town on the Senegal River. This is where we rescued manatees trapped behind a dam in January 2009, and it's the place where manatees migrate in the rainy season onto a huge floodplain to feed on submerged grasses and plants in this otherwise extremely dry region.  It's a 12-hour drive through dust and many small villages to get to this part of the world, so this time we split the drive up by spending a night at Lac de Guiers and arrived in Matam on the 10th.

Our first task in Matam was to recover and clean three manatee skeletons that were buried to decompose last November.  Unfortunately these three manatees likely died while trying to exit the Navel dam as the waters receded after the rainy season last fall. Unfortunately, grates on the dam doors were not lifted, so they probably drowned as they were trapped. Some interested kids watched Tomas and I cleaning skulls. We hope at least the bones of this rare species will be useful for science and educational purposes in Senegal.

We checked the rest of the bones, but found that due to the extremely dry soil (it hasn't rained here since August) they haven't finished decomposing. So we collected a few more, but we'll have to wait for the rest.

Next we checked the water level at the Navel tributary. The dam doors are now closed and this water is being used for crops, but there are still some manatees trapped inside (no one knows how many since this tributary, full of ruddy-colored water, that runs for miles). We scouted for them but didn't see any, and I also listened for the radio-tagged manatee (the only one still tagged from January 2009), but I didn't hear her signal at this location.

The water is slowly receding, but it's still a lot higher than it was in January 2009. Unfortunately for the trapped manatees, the water needs to be lower in order for captures to occur. All the captures are done by hand nets, so the water can't be over people's heads, and we need to limit the manatees to a smaller area to catch them. But I did see several places where plants were in reach of the water, so they may still be able to find food.

Next we traveled about 35 kilometers south down the road to the town of Kanel, another part of the huge floodplain. Here the water has always formed large pools (really lakes several miles long) as the tributary dries up. So this is an area where manatees become trapped as well. I learned that the first manatee captures here were in 1964, so the people here have a long history of returning the manatees to the Senegal River. We went out on the Wendou Kanel lake in a boat with a fisherman named Moutar, who took me out tracking last fall. I was happy to see a huge area of flooded grasses and waterlilies (both known manatee food plants) along one side of the lake.

As always, I listened for the tagged manatee. I heard the signal a few times, but it was extremely faint and off to the south. It's very hard to get around this area (there are no roads) and even though we went to the south end of this lake, she could be in a completely different area.

The last site we visited was Patowel, another part of the tribuary cut off from the main Senegal River, approximately 7km long. The water here never completely dries up and it's an important fishing spot for the local people (the fish are refreshed during the rainy season with overflow from the main river). Manatees get trapped in here every year and there are almost no plants during the dry season, so they eat fish from the fishermen's nets. This occurs in other countries as well, and African manatees are reported to eat not only fish but several species of clams throughout Africa, so they are more omnivorous than their Floirida cousins!

Patowel fisherman cast large nets across the entire river, that manatees break through. It's challenging to explain to the fishermen that if they don't want their nets broken, they are going to have to alter their fishing practices and leave an open space for manatees to pass by...they would not welcome hearing this from an outsider, so I discussed this with the local fisheries representative, a very enthisiastic guy who is very interested in finding good solutions for both fishermen and manatees.

At the end of our tip, Tomas and I attended a 2 day multi-agency meeting hosted by Wetlands International in Matam. The meeting brought together all the interested parties in manatee issues on the Senegal River including government agencies (manatees are a protected species under the Water and Forestry Ministry, but the water bodies are overseen by the Senegal River Development Authority, and there are also local fisheries departments), NGOs (Wetlands and Oceanium Dakar, both of whom I collaborate with), and local elders from the various villages. There were also several journalists there.

An engineer with the Senegal River Authority discussed the Navel dam.  I learned a lot at this meeting and it was impressive to see all the interest in finding solutions from all the different attendees.

Last but not least, Tomas had learned of some old photos of manatee captures in Matam, and we tracked them down. They had not been well-preserved, but it was still neat to see them. Oceanium began working on manatee rescues here in 1986.

I always enjoy the trips to eastern Senegal, but it's also good to get back to Dakar and wash off the dust! I'm now planning my next field trip to southern Senegal - stay tuned!

Reporting from West Africa, EcoHealth Alliance research scientist Lucy Keith is working on an extensive collaborative project to study West African manatees.