Presented during the 17h Annual Sahelo-Saharan Interest Group Meeting organized by the NGO Sahara Conservation Fund in Senegal, from 4 to 6 May 2017. The Sahara Conservation Fund (SCF) gathers every year about a hundred people who are interested in the field of Sahelo-Saharan species conservation.

1. 17th Annual Sahelo-Saharan Interest Group Meeting
2 days of talks on biodiversity conservation in the Sahara and in the Sahel
Research on Conservation of Sea Cows in the Sahel
Lucy KEITH-DIAGNE, Executive Director - African Aquatic Conservation Fund
May 4– 6, 2017

2. Sea Cows in the Sahel: Research and
Conservation on the African Manatee
(Trichechus senegalensis) in the Senegal and
Niger River Basins
Lucy Keith-Diagne, PhD
Photo courtesy of SAED, Senegal

3. African Manatee General Facts
§ First specimen for science collected by Michel Adanson in
the Senegal River, 1752. Described by Link, 1795.
§ Average length is 249 cm, estimated weight 440 –
880 lbs. (200 - 400 kg).
§ Life span is at least 39 years
§ Most closely related to W. Indian manatees but smaller
§ Most life history parameters are unknown (age of maturity,
calving interval, home range size, etc.)

4. African Manatee Species Overview
§ Hunting and fisheries bycatch are the biggest
threats, followed by dams, human development,
and habitat destruction
§ Protected by national laws in all range countries
§ IUCN Red List classification: Vulnerable
§ Appendix I species under CITES and CMS
§ Live in a wide range of different ecosystems across
their 21 country range

5. `
Map courtesy of Ellen McIlhinny and Ellen HinesBase map courtesy of Ellen McIllhinney
Existing major dams
Major dams under
construction

6. § Began in Gabon in 2006
§ Country-wide distribution surveys and threat
assessments
§ Genetics: population level analysis
§ Feeding Ecology: analysis of manatee food sources
and habitat use
§ Age determination study
§ Manatee rescues (orphans, injured)
§ Training programs
§ Educational outreach
§ Alternative livelihood programs
§ Lead network with collaborators in 19 countries
African Manatee Project Overview

7. Genetics Research Questions
§ How many different distinct populations are there across the
species range?
§ What is the genetic diversity of the species across its range?
§ Are populations isolated by dams in trouble?
§ What impact is hunting having on populations?
§ Evolution in relation to other manatee species
Results will be used for conservation actions-
working to save the most endangered populations

8. Southern
regional clade
Niger
River
Northern
regional clade
Mitochondrial DNA
Control Region
West Indian manatee

9. Base map courtesy of Ellen McIlhinny
n=20
n=18 n=2
n=1
n=1
n=1
n=10n=2
n=2 n=2
Current North-South
population boundary
Haplotype
Number
of Seqs Color
TS-CR01 12
TS-CR02 2
TS-CR03 2
TS-CR04 2
TS-CR05 1
TS-CR06 1
TS-CR07 8
TS-CR08 3
TS-CR09 1
TS-CR10 2
TS-CR11 1
TS-CR12 2
TS-CR13 2
TS-CR14 2
TS-CR15 1
TS-CR16 3
Y01 Guinea-Bissau 1
Y02 Guinea Bissau 1
Y02 Senegal
coast* 2
Y03 Ghana 1
Y03 Cote D'Ivoire* 1
Y03 Gabon* 8
Y04 Chad 1
Y04 Niger* 1
Y05 Niger 1
n=4
Control Region Haplotypes

10. Control Region Haplotypes

11. Control Region Haplotypes- Niger River

12. Results: Control Region Divergence Dating
Tree created by S. Chen and R. Hodel

13. § First satellite tracking study of the African manatee
§ 5 manatees rescued Jan. 14-15, 2009 (3 males, 2 females)
§ Morphometrics, genetics samples, and ID photos collected
§ 3 manatees satellite tagged (2 males, 1 female)
§ Transported 6.4 km to the release site by tractor with trailer
Senegal River Tracking study
Navel Dam

14. § Tracking periods lasted
between 86-325 days.
§ Tagged manatees used over
308 km of the Senegal River,
north and the south of the
release location.
§ Each manatee had very
different movement patterns,
but all three made directed
trips to specific locations.
§ The female was confirmed
returning to a flooded area at
Kanel at the end of the dry
season.
§ The Navel dam grates were
removed, and no manatees
were subsequently trapped
Results
Mboumba
Bababé
Kaédi
Matam
Kanel
Bakel
Bokiladji

15. Feeding Ecology
§ African manatees live in a wide range of habitats from Sahel to
rainforest, so their diet is expected to vary between ecosystems
§ African manatees are difficult to study in the wild
§ Local people report that African manatees eat mollusks and fish
throughout their range
§ When we understand what food resources manatees need, we
will know which habitats to protect
© Tomas Diagne
3 manatee noses, Navel, Senegal
Catfish eaten by manatees, Patouwel,
Senegal

16. Stable Isotope
Results-
Senegal River
Food species
GLG, Recent GLG, Historic
Internal,
Recent
Internal,
Historic
A. dahomeyensis (mussel) 0.06 0.09 0.08 0.09
C. aegyptiaca (mussel) 0.06 0.09 0.09 0.09
M. rostrata (mussel) 0.06 0.09 0.09 0.09
Mollusk total proportion 0.19 0.26 0.25 0.27
A. macrolepidotus (silverfish) 0.08 0.09 0.10 0.09
C. anguillaris (catfish) 0.07 0.08 0.09 0.09
Synodontis sp. (catfish) 0.09 0.09 0.10 0.09
Fish total proportion 0.24 0.26 0.29 0.27
C. natans 0.14 0.12 0.11 0.11
Echinochloa sp. 3 0.15 0.12 0.12 0.12
Echinochloa sp. 4 0.16 0.12 0.12 0.12
Najas sp. 0.12 0.12 0.11 0.11
Plant total proportion 0.57 0.48 0.46 0.46
Manatees
n = 7
Recent, n = 5
Historic, n = 2

17. Educational Outreach
§ Over 50 programs conducted last
year in Senegal, Gabon, Mali, Nigeria,
and Cameroon
§ 5000 people reached annually
§ Materials developed for use in
multiple countries
§Art contests
§Gabon: murals, effectiveness study

18. African Manatee Regional Network
§ Over 90 African biologists from 19
countries trained since 2008
§ Basic field equipment provided to
researchers in 11 countries
§ Manatee fieldwork has increased in at
least 10 countries
§ Increased knowledge about the species
now directs conservation actions
Nigeria Cameroon 2014
Benin
© Tomas Diagne
© Aristide Kamla© Edem Eniang

19. Thanks to
MANY
African
colleagues

20. Acknowledgements:

21. Thank
You!!
africanaquaticconservation.org