Standards GS 175 of zero tolerance for coliform bacteria. This suggests that the consumption of the water without treatment could pose serious health threats to the community who depend on
the lagoon for drinking water.
3.2.2 Biodiversity
3.2.2.1 Macrobenthic fauna The macrobenthic fauna composition within the lagoon comprised of only three taxonomic
groups – Isopods, Polychaetes and ‘Other’ taxa Table 3. Isopods were solely represented by Excirolana latipes, polychaetes by Capitella capitata, whilst chironomids constituted the ‘Other’
taxa.
Table 3. Abundance of major macrobenthic faunal groups in Belibangara lagoon
Taxa Abundance
Percent Abundance
Isopods 10
71.4 Polychaetes
2 14.3
Others 2
14.3 Total
14 100
3.2.3 Avifauna
Shorebirds’ populations at Belibangara was relatively low, with only two species recorded one bird each of Actophilornis africanus Africa jackana and Milvus migrans Black kite. This
could possibly due to unreliable source of food items for these birds due to unexposed substrate as a result of high water level. Exposure of wetland substrate could lead to rapid exposure of
fresh patches of unexploited feeding areas which would consequently attract foraging birds. Foraging waterbirds are uncertain about their chances of success on arrival at a patch and
therefore sample their environment to get information on the presence of food so as to ‘make decisions’. Since the decision on whether to keep on feeding or leave a patch depends largely on
prey encounter rates. It is therefore reasonable to assume that the low numbers of birds is related to low encounter rate of prey items e.g. invertebrates possibly due to organic pollution as
indicated by high levels of nitrate. The observation is expected due to high residence time and low flushing rate of pollutants since the water body is an enclosed system.
3.2.4 Fisheries
3.2.4.1 Fishing Effort Fishing was the most popular profession or pastime among male adults in the community, who
fished in the lagoon all year round. This made the fishing effort on the lagoon very high. The natives stated that there were about 50 commercialsubsistence set nets in the Newtown
community. However, almost every family had at least one cast net which it uses to fish mainly for subsistence in support of protein needs. Because drag nets are non-selective and perceived as
destructive by natives, a traditional management practice has banned its use in the lagoon. The
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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
