Saturday, October 17, 2009

Senegal: Delta Saloum

Last week I spent three days in the northern part of the Saloum Delta, a huge mangrove estuary in central Senegal. It s a beautiful area with salt flats filled with flamingoes, savannah with giant baobab trees, countless mangrove channels and lots of fishing boats. I had a chance to talk to many fishermen about manatees there and to distribute informational posters, which they eagerly took. People were very curious to learn more about a creature they consider spiritual and mysterious. Manatees are still hunted in this area, although they are rare now and only one or two are caught per year.

Interestingly, most of the manatee carcass data that Buddy Powell was able to collect for the species in the 1980's and 90's came from this area. There is a marine protected area in the south of the Delta, but I wasn't able to get there this time. I hope to do more work here in the future.

My internet connection time is limited at the moment, so here are a few pictures to give an idea of the place and what I did there:

Fishermen in Ndangane check out manatee informational posters in French to learn more about the species. They told me that only certain families are manatee hunters and that it is believed these people can communicate with the manatees. They also told me about a number of freshwater springs in the area where manatees come to drink.
Young boys with posters and stickers. Although the manatee is hunted here, it is also revered and there's a general sense of fascination about them. People say they are no longer hunted in the protected area because they know they will get in trouble. It's a start to protection!
Beautiful, brightly colored fishing boats at Ndangane
The view at the place where we stayed- gorgeous!
There are numerous intiatives to re-plant mangroves in the area- some efforts are led by NGOs while others are led directly by the people and their communities. This photo shows 2 species (the ones on top of the sandbar are a different species from the one in the water, I need to get correct species names!). It is great to see environmental initiatives going strong here, hopefully that will lead to awareness and protection for many species. We were able to go to one of the freshwater springs by boat but it was late in the day and I couldn't jump in and check it out. It is hard to see, but it's situated between the two sandbars in the photo below. Manatees generally come at night, and I am sure this is related to hunting pressure.
Flamingoes at sunset on the mudflat
I also met with village elders at Ndangane who had interesting perspectives on hunting techniques
At the end of the trip I met a very cool guy named Doudou at Joal (left). He has worked on fisheries bycatch issues previously and had reports of manatee carcasses going back many years. Here he shows me a manatee bone he took from a carcass in 2004 (that's his wife in the middle). As we drove along we came upon this sign purely by chance! Of course we searched for and found the place and met the owner, Anne-Catherine, who is a neat lady. After working in the pharmacutical industry for many years she decided to start an ecotourism venture that includes both environmental and cultural awareness. Eventually she hopes to open a hotel there, but for now there is a nice restaurant, a library and a beautiful lodge overlooking the water. We had a great conversation about manatees and I hope to plan future work together. This manatee trap was at Source Aux Lamantins and shows how hunters set traps in mangroves where manatees feed. They sit on top of the trap at night and when the manatee bumps the trap, they harpoon it. Luckily this one is no longer in use, it's only for educational purposes.
This morning I arrived in Accra, Ghana, and tomorrow I head out to the Afram Arm of Lake Volta to co-teach a manatee research and conservation workshop for African biologists. We have 8 participants from 8 different countries and I'll write lots more about it when I return to internet in 2 weeks!

Saturday, October 10, 2009

Senegal: Diama Dam On our way back to Dakar we stopped at the Diama Dam, built in 1984 near St. Louis at the mouth of the Senegal River. This dam now traps manatees in the river and although they have well over 600 km of river to use, as well as Lac de Guiers and much more area during the rainy season when the river floods the plains, these manatees are isolated here with no way to leave or breed with other manatee populations. In the dry season, food plants can be scarce, and although there doesn't seem to be much targeted hunting, manatees do get caught in fishing nets and drown fairly frequently. And of course they get caught behind smaller dams near Matam and Kanel. At the southeastern end of the river they are hemmed in by a hydroelectric dam in Mali. So there are many challenges for this population.
The dam in Mali provides power far into the interior of Senegal; these power lines near Kanel are over 200 km away from the dam.

But there's good news too. There is very good habitat in Lac de Guiers (a huge man-made lake which provides the drinking water for all of Dakar and water for farm irrigation for hundreds of miles surrounding the lake) with lots of the manatees favorite food plants. Dams keep the water in Lac de Guiers high year round and the manatees have learned they no longer need to migrate back to the river during the dry season.
Lots of water lilies and grasses in Lac de Guiers

And as I mentioned in my previous post, they have lots of food on the flood plain during the rainy season. From what I've seen so far, I think the Senegal River supports a fairly healthy manatee population, and I'm happy that many people, government agencies and private organizations here are interested to conserve them.

Downstream and seaward of the Diama Dam is the Senegal River delta, and it is unknown if manatees still use this area as well. It will be interesting to try to find out!
Water flowing out of the Diama Dam towards the ocean.

Friday, October 09, 2009

Senegal: To Kanel and Back
Our trip last week got off to a rough start. The first day we left Dakar at 6am and our rented car and driver (many rented cars here come with a driver) drove us 3 hours north of Dakar to the colonial era town of St. Louis. We had breakfast there and afterward expected to continue on the long trip to Matam. However, at this point it became clear there was a misunderstanding. The driver had been told we only wanted to go as far as St. Louis. Many calls ensued between the driver and the owner of the car, and after a heated discussion it became apparent we had no choice but to return to Dakar, because the car’s owner did not want us taking the car further into the desert. So we then spent another 3 ½ hours driving all the way back to Dakar, then there was a heated discussion with the owner who did not want to refund any of the money we paid for 5 days of rental, and finally the search for another car. At that point it was too late to begin the long trip again, so we tried again the next day.
The second attempt was a successful, if hot and dusty, 13 hour trip to Matam in eastern Senegal. On the way we got the first of three flat tires during the trip- the paved road is basically a series of giant pot-holes much of the way, and cars weave between them, coming at each other and missing by inches, driving off the paved road onto the dirt road that borders and continuing at high speed. Every car carries 2 or 3 spare tires. Huge herds of goats, sheep and cows graze everywhere and often stand in the road, we had to nudge the car through them countless times every hour. It was amazing to see how the desert tansformed with the rains; what had been a few scrubby trees in the red sand last January were now lush trees in a sea of grasses, crops of sorghum and melons, with the flood plain of the Senegal River clearly in view (the actual river is normally out of sight from the road). Dashboard view: Koran and prayer beads, dust, small towns, lots of goats and donkey carts!

Once we reached Matam, an air-conditioned room and a cold shower was an absolute slice of heaven. We were also treated to wonderful meals and hospitality by Commandant Seck and his family- he oversees the dams and irrigation for the Matam area and has been extremely interested to help manatees from getting trapped by the dams. He was the person who donated use of a tractor and trailer last January so we could tasnsport the stranded manatees back to the main Senegal River.
For each of the next 3 days we started out at 5am and drove another hour south from Matam to the town of Kanel. Between Matam and Kanel the river had expanded from its channel into an enormous flood plain, approximately 35 km long and 12 km wide. This is only one of many areas along the length of the river that has flooded and covered huge areas with water, flooding trees and allowing catfish and manatees to swim where cows graze in the dry season. For the manatees it becomes a wonderful feeding area, with tall grasses and water lilies stick up through the water. For us it was incredible to see the transformation, but daunting to try to find one tagged manatee in miles of water with only a non-motorized canoe!
Sunrise at Kanel
Egrets fly near flooded trees. The blobs at the top of the tree are weaverbird colony nests.

We went out with three guys from Kanel who in previous years helped rescue stranded manatees when the water dried up. They had seen several mating herds the week before and took us to those places, but unfortunately hours of scanning the water in the scorching sun didn’t turn up any manatees. At the same time we listened for the tagged manatee, who was supposed to be in the area, but we didn’t hear the VHF signal. It was still really interesting to see the area though and to realize the importance of the flooding in the manatee's feeding life cycle.
Heading out in a tippy canoe with all our gear, the air still and hot
Tomas shows the guys how to use the VHF receiver.
Scanning, scanning, scanning...
People from the village were swimming and washing their animals in the flooded plain

On the first evening we went to the Navel Dam, the place where were rescued and tagged manatees last January. It was astounding to see the difference in the water levels:
This is the Navel Dam in November 2008 near the height of the dry season (photo courtesy of P. Fernandez de Larrinoa)
This is the Navel Dam last week, with water level 9 meters higher
This was the Navel manatee rescue site last January. Note the cliff edge in the foreground.
This is a photo taken at the same site last week, with water almost to the top of the cliff.

I brought along the VHF receiver to the dam, because the tagged manatee could be anywhere and the receiver only works at a range of about 3 km. After listening to static for awhile, suddenly we heard the signal! It was incredible luck considering the size of the flooded area. The signal was faint, meaning the manatee was not close by, and came intermittently, meaning she was probably traveling, so the tag was only coming to the surface of the water every few minutes. We listened for 45 minutes before it got dark. It was frustrating not to be able to get closer to see her, but there are no roads along the river's edge and we didn't have a boat to search by water.
Tomas took this photo just as I heard the signal... surprise and happiness!

We tried listening for the signal the following two evenings at Navel, but we didn't hear it again. I hoped she was heading south and that maybe we would hear the signal from the Kanel side during our boat surveys, but the area was too huge and our ability to cover it too limited. However, it was still great to hear the tag at all, to know she's still in the general vicinity of Matam and that the VHF portion of the tag is working.
While in Matam we had nice meetings with many of the people who are interested to help the manatees: Eaux et Forets (Water and Forestry), the Matam and Navel Fisheries Commissioners. After 3 days we started back to Dakar, making a few stops along the way, which I'll write more about next.