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Seth Mensah Abobi


+49 421 23800-160



ZMT, room 3006

Seth Mensah Abobi
Institution: Leib­niz Cen­ter for Trop­ical Mar­ine Eco­logy (ZMT), Bre­men
Other webpage(s): Seth's ZMT web page


PhD project:

Fish­er­ies As­sess­ment and Trophic Mod­el­ling of Tono, Bontanga and Golinga Reser­voirs in North­ern Ghana

Tono, Bontanga and Golinga reser­voirs are among the top five largest reser­voirs in the North­ern Ghana. These reser­voirs are used for ir­rig­a­tional farm­ing and fish­ing. They are es­sen­tial food se­cur­ity and live­li­hood re­source for the rural ma­jor­ity poor in their catch­ment areas.

Reser­voir con­struc­tion has gained strong at­ten­tion in Ghana as Gov­ern­ment and polit­ical parties have re­peatedly ex­pressed plans to re­vamp ex­ist­ing reser­voirs and con­struct new ones. The po­ten­tial con­tri­bu­tion of the reser­voirs to in­land fish pro­duc­tion is huge, grant­ing that the reser­voirs are tech­nic­ally and pur­pose­fully de­signed and con­struc­ted to provide sig­ni­fic­ant fish pro­duc­tion and grant­ing that the fish­er­ies which sub­sequently de­velop are sus­tain­ably man­aged. However, the ac­tual be­ne­fit de­rived from most of the ex­ist­ing reser­voirs in terms of fish pro­duc­tion is in­sig­ni­fic­ant and the reas­ons are mul­ti­fa­ceted, en­com­passing is­sues such as un­pro­duct­ive reser­voir designs, bad fish­ing prac­tices, plan­ning and policy, re­search and de­vel­op­ment, man­age­ment and ex­ploit­a­tion, fin­ance and hu­man re­source, among oth­ers.

The Tono, Bontanga and Golinga reser­voirs have dif­fer­ent phys­ical fea­tures and the main ob­ject­ive of this PhD pro­ject is to understand how differences in reservoir morphometry (total size, surface area/volume ratio), water budget (inflow, precipitation/evaporation ratio) and physicochemical conditions influence the development of ecosystem structures and fisheries productivity.
The PhD pro­ject has three main areas of fo­cus namely:

  1. Elucidating difference in fisheries productivity of Tono, Bontanga and Golinga reservoirs: Relating age, morphometric and hydrochemical features of the reservoirs to their productivity
  2. Fisheries assessment of target species of Tono, Bontanga and Golinga reservoirs: Elaborating management advice for Auchenoglanis occidentalis, Oreochromis niloticus, Sarotherodon galilaeus, and Tilapia zillii
  3. Comparative analysis of biodiversity, food web structure and fisheries productivity of Tono, Bontanga and Golinga reservoirs: Assessing differences in ecosystem attributes among the reservoirs

My PhD pro­ject fo­cuses on de­fin­ing a range of phys­ical at­trib­utes and de­vel­op­mental con­di­tions un­der which man-made reser­voirs can provide and sus­tain sig­ni­fic­ant fish­er­ies pro­duc­tion. Moreover, fish­er­ies man­age­ment in reser­voirs re­quires al­tern­at­ive sus­tain­able man­age­ment scen­arios which are de­riv­able from eco­sys­tem mod­el­ling, for ex­ample, us­ing eco­sys­tem mod­el­ling soft­ware ECO­PATH with ECO­SIM. As ob­served for other fish­er­ies eco­sys­tems, sus­tain­able ex­ploit­a­tion of the Tono, Bontanga and Golinga reser­voirs is ne­ces­sary if the fish­er­ies are to make any sig­ni­fic­ant con­tinu­ous im­pacts on the so­cio-eco­nomic life of the rural com­munit­ies around the reser­voirs. Sub­sequently, the study will elab­or­ate man­age­ment ad­vice for sus­tain­able ex­ploit­a­tion of the reser­voirs fish­ery.

Thesis committee:

Prof. Dr. Matthias Wolff University of Bremen and Leibniz Center for Tropical Marine Ecology (ZMT)
Dr. Werner Ekau Leibniz Center for Tropical Marine Ecology (ZMT)
Prof. Dr. Achim Schlüter Jacobs University and Leibniz Center for Tropical Marine Ecology (ZMT)


GLOMAR Research Theme C