cast net and set nets are deployed using planked canoes that have a dual purpose of transportation and fishing. Ten of these crafts were counted at the landing site during the survey period.
3.2.4.2 Experimental Fishing Experimental fishing using two cast nets by two fishers for one hour each, in the early hours of
the morning yielded a total catch of 18 individual fishes from three families and four genera Table 4. Chrysicthys nigrodigitatus was the dominant species. One of the fishermen had
samples of all the genera, while the other had samples of only Sarotherodon and Chrysicthys sp. On average, the total weight of fish caught per fisherman in one hour was 653 g, at a cost of
Three Ghana Cedis fifty pesewas GH¢3.50 per fisherman per hour.
Table 4. Results of experimental fishing at Belibangara
Family Species
TN ASL cm
AW g
Cichlidae Sarotherodon melanotheron
4 15.8
178.8 Tilapia zillii
4 10.1
38.8 Bagridae
Chrysicthys nigrodigitatus 8
13.9 53.9
Mormyridae Mormyrus rume
2 7.9
12.5
TN = Total number; ASL=Average Standard Length; AW = Average Weight
3.2.5 Fish Composition
The inhabitants noted that in the past years, the lagoon hosted rich variety of fish species that occurred in great abundance. Some of the fish species mentioned as being caught in the past
were: Tilapia zillii, Sarotherodon melanotheron, Polypterus endlicheri, Mormyrus rume, Hepsetus odoe, H. niloticus, Citharinus spp., Schilbe mystus, Alestes spp., Clarias spp.,
Chrysicthys spp., and Channa obscura. The dominant species, according to them, in the past and in recent times, were fishes from the tilapia and catfish families. However, there has been a
general decline in species richness caught in the recent years, although abundance is relatively higher during the rainy season compared to the dry season when the lagoon reduced in size.
Inhabitants attributed the observed decline in fish catch and diversity mainly to excessive human pressure due to population increase and the use of small mesh sizes of nets.
3.2.6 Critical Features and Conservation Significance
The Belibangara Lagoon is important as a fresh water resource for the surrounding community for their domestic use. Various human activities washing, bathing near and in the lagoon, in
addition to decaying vegetation, has possibly influenced the high levels of nutrients recorded. This also contributes to siltation and the growth of aquatic vegetation, which may lead to the low
aquatic biodiversity observed. The distinct location of the lagoon near the country’s western border with Cote d’Ivoire, and it being a unique freshwater lagoon, provides satisfactory
justification for protection.
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3.3
Domunli
The Domunli Lagoon is an open lagoon which stretches over an area of 1560 km
2
. It is located in the Jomoro District of the Western Region Appendix 2, adjacent to Old Kabensuazo. The
Domunli wetland, although relatively small, has an intact and beautiful and healthy mangrove forest and estuary Figure 3. It is inhabited by monkeys, crocodiles, marine turtles and birds.
The wetland hosts significant numbers of Tilapia spp. due to minimal fishing in the lagoon. This is due to abundant mats of Enteromorpha clathrata which destroy the fishing nets and
discourages large scale fishing by the community members.
Figure 3. Domunli Lagoon with fringing mangroves and coconut trees 3.3.1 Water quality
A bloom of the green algae Enteromorpha clatharata, previously identified as E. flexuosa personal communication with Francis Seku was observed in the lagoon during the study period.
This observation was supported by high mean concentration of chlorophyll-a recorded Appendix 9. According to the community members, the bloom was brought in from the
adjacent marine environment through inflows into the lagoon.
High concentration of phosphate measured in the lagoon could possibly sustain the algal bloom. Although the sources of the phosphate into the lagoon are unclear, run-offs from the surrounding
agricultural fields and from dump sites observed along the fringes of the lagoon could be contributing factors. According to the inhabitants, there are no toilets in the village and most
people defecate in holes that are dug along on the beach, which are later covered. In addition,
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high BOD levels indicate excessive amounts of dissolved organic matter DOM in the lagoon possibly from decomposing E. Clatharata, aquatic vegetation and organic waste discharges from
the surrounding communities. Levels of Cu, Zn and Fe recorded here were also below WHO acceptable standards Appendix 9.
3.3.2 Biodiversity
