Table 18. Number of species of fauna and macroalgae at Butre Taxa
No. of species Percentage
Fauna Gastropods
7 43.75 Bivalves
2 12.50 Crustacean
7 43.75 Total
16 100.00
Macroalgae Chlorophyta
5 35.71 Phaeophyta
4 28.57 Rhodophyta
5 35.71 Total
14 100.00
Figure 25. Mouth of Butre estuary depicting populations of Brachydontes sp. and Ostrea tulipa
3.11.3 Critical Features and Conservation Significance
The existing traditional conservation measures should be strengthened to help protect biodiversity of the area. This can be achieved by educating community to raise awareness on
values of habitat and biodiversity of the area thereby providing understanding for enforcement of traditional conservation measures.
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4 COMPARATIVE ASSESSMENT OF KEY CRITICAL HABITATS AND RECOMMENDATIONS FOR MANAGEMENT
4.1
Overview of ecosystems of the Western Regions
This chapter presents a comparative discussion of the critical habitats assessed based on the different indicators measured. This is to categorize the habitats in terms of the quality and
healthiness of the systems. Where rankings are presented, they are based purely on the quality of the habitats drawing on existing scientific concepts. Section 4.1.2., however, provides a detailed
description of findings from terrestrial faunal survey covering seven out of ten studied habitats. The essence of these comparative analyses was to help derive recommendations for future
management.
4.1.1 Water quality
In terms of water quality indicators, levels of dissolved oxygen DO, and biochemical oxygen demand BOD, nutrients e.g nitrates and phosphates, temperature, total dissolved solids, and
trace metals are crucial. Water quality standards may be set for these water indicators depending on the purpose for which the water is required. For instance, a water body with BOD of less than
2 mg l
-1
is generally regarded as unpolluted, while one with a BOD of more than 10 mg l
-1
is considered as grossly polluted Clark, 2003. Although BOD level of up to 7 mg l
-1
may be considered acceptable for drinking water Clark, 2003, the overall suitability of water for
consumption may depend on many other factors such as levels of bacteria, nitrates and other chemical contaminants.
Among the water bodies studied, Belibangara and Amansuri main were purely freshwater while the others were saline. Thus, Belibangara and Amansuri- main serve as sources of drinking water
for the local inhabitants. For water to be considered fit for human consumption, it should have no fecal coliform units or zero CFU100 ml WHO, 1987. The detection of total and fecal coliform
levels of 504 and 163 CFU100 ml respectively for Belibangara and 428 and 194 CFU100 ml respectively for Amansuri-main therefore suggests fecal pollution. In the light of the observed
levels of fecal coliform in these two water bodies, consumption of these waters could pose as human health risk, especially if general sanitary conditions deteriorates. At Belibangara, the
residents bath in the freshwater lagoon, while at Amansuri- main, it was obvious that domestic waste water and human excreta could be easily discharged into the water body without treatment.
Wild and domestic animals seeking water can also contaminate these two water bodies through direct defecation and urination. These two water bodies are therefore not suitable for drinking
without treatment. The levels of trace metals such as Zn, Cu, Fe, Hg and As detected in the selected water bodies exceeded their acceptable limits for aquatic life and could therefore impact
negatively on aquatic life.
The Ankobra estuary had high turbidity and high levels of toxic elements such as Hg and As. High turbidity indicates the presence of suspended organic materials which promotes the growth
of microorganisms WRC, 1993. It recorded the highest heterotrophic bacteria counts of 1540 CFU100 ml indicating the generally poor biological quality of the estuary. Although the total
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and fecal coliform counts were within limits, this water body is not recommended for recreation, swimming or bathing due to the current state of pollution.
Domunli is saline and colonised by the green algae Enteromorpha clathrata. Not surprisingly, it recorded the highest level of chlorophyll-a. Levels of BOD and bacteriological load were within
acceptable limits and could be useful for tourism if the issue of Enteromorpha bloom is dealt with permanently. By far, Amansuri outlet, Butre and Kpani-Nyila are among the best lagoons
for recreation, especially swimming. This is because the water quality indicators are generally within acceptable limits with zero fecal 100 ml being recorded for Kpani-Nyila.
4.1.2 Biodiversity
