The Plankton community RESULTS 1 Spatial information on the wetlands

42 7.4 7.5 7.6 7.7 7.8 7.9 8 8.1 8.2 8.3 8.4 A B C D E F G Stations pH Essei Butuah Whin Figure 14: pH profile of the wetlands

4.3 The Plankton community

Plankton diversity were measured and used as indicators for comparative assessment of the primary productivity of the wetlands to be able to support fish resources. Phytoplankton As shown in Tables 4-6, the phytoplankton identified from the three water bodies includes species of blue-green algae, green algae and diatoms. The blue-green algae found include Anabaena spp., Oscillatoria spp., Chroococcus sp., Microcystis sp. etc., while the green algae were mostly desmids such as Closterium sp. and Scenedesmus sp., unicellular forms eg. Pediastrum sp. and Staurastrum sp. and a few filamentous types 43 such as Spirogyra sp.. The most common diatoms present include species of Navicula , Rhizosolenia , Gyrosigma , Diatoma spp. and Stephanodiscus . Table 4: List of phytoplankton in Essei Lagoon in the Sekondi – Takoradi metropolis PHYTOPLANKTON ABUNDANCE Blue - green algae Oscillatoria spp. ++ Anabaena spp. ++ Lyngbya sp. ++ Spirulina spp. + Microcystis spp. +++ Chroococcus sp. ++ Aphanizomenon sp. + Diatoms Navicula spp. +++ Nitzschia spp. ++ Gyrosigma sp. + Coscinodiscus spp. +++ Stephanodiscus spp. +++ Melosira sp. + Rhizosolenia spp. ++ Diatoma spp. +++ Asterionella sp. + Synedra spp. + Green algae Staurastrum spp. ++ Pediastrum sp. + Spirogyra sp. + Netrium spp. + Microspora sp. + Closterium sp. + Chaetomorpha sp. + + = occurred sparingly + + = moderately abundant +++ = highly abundant 44 Table 5: List of phytoplankton in Butuah Lagoon in the Sekondi – Takoradi metropolis PHYTOPLANKTON ABUNDANCE Blue - green algae Oscillatoria spp. ++ Anabaena spp. +++ Lyngbya sp. +++ Spirulina spp. ++ Calothrix sp. ++ Microcystis spp. +++ Chroococcus sp. +++ Aphanizomenon sp. + Diatoms Navicula spp. ++ Nitzschia spp. + Pleurosigma sp. + Stephanodiscus spp. + Rhizosolenia spp. ++ Diatoma spp. ++ Synedra spp. + Green algae Staurastrum spp. + Netrium spp. + Microspora sp. ++ Scenedesmus sp. + + = occurred sparingly + + = moderately abundant +++ = highly abundant 45 Table 6: List of phytoplankton inWhin Estuary in the Sekondi – Takoradi metropolis PHYTOPLANKTON ABUNDANCE Blue - green algae Oscillatoria spp. + Anabaena spp. ++ Spirulina spp. + Microcystis spp. ++ Chroococcus sp. ++ Diatoms Navicula spp. +++ Nitzschia spp. ++ Gyrosigma sp. + Pleurosigma sp. + Coscinodiscus spp. + Stephanodiscus spp. + Melosira sp. +++ Rhizosolenia spp. ++ Diatoma spp. +++ Asterionella sp. ++ Synedra spp. ++ Cyclotella sp. + Green algae Staurastrum spp. +++ Pediastrum sp. +++ Spirogyra sp. + Netrium spp. ++ Microspora sp. +++ Closterium sp. +++ Scenedesmus sp. ++ Chaetomorpha sp. ++ + = occurred sparingly + + = moderately abundant +++ = highly abundant A total of 25 genera of phytoplankton occurred in the Whin Estuary, 24 in the Essei Lagoon and 19 in Butuah Lagoon Table 10. Generally, more genera of diatoms and 46 green algae occurred in the Whin Estuary than Essei and Butuah, while Butuah had the highest number of genera of blue – green algae. There was a high abundance of blue – green algae than green algae and diatoms in Butuah, and green algae were highly abundant in Whin. The abundance of diatoms was higher in Essei and Whin than Butuah. The list of zooplankton identified from the three water bodies is presented in Tables 6-8. Species of copepods Calanus sp., Sappharina spp., Cyclops spp. , Thermocyclops sp. , and Copepodite sp., rotifers Brachionus sp., Keratella spp., Kellicottia spp., and Trichocera sp. and a cladoceran Bosmina sp. were the zooplankton encountered. A total of 10 zooplankton genera were found in Whin, and 7 in each of Essei and Butuah Lagoon Table 10. A higher number of genera of copepods and rotifers occurred in Whin Estuary than Essei and Butuah, while the 1 cladoceran genus occurred in the three water bodies. Table 7: List zooplankton in the Essei Lagoon in the Sekondi – Takoradi metropolis ZOOPLANKTON ABUNDANCE Copepods Calanus sp. + Cyclops spp. ++ Sappharina sp. + Rotifers Brachionu s sp. + Keratella spp. +++ Kellicottia spp. ++ Cladocerans Bosmina sp. ++ + = occurred sparingly + + = moderately abundant 47 ZOOPLANKTON ABUNDANCE +++ = highly abundant Table 8: List of zooplankton in the Butuah Lagoon in the Sekondi – Takoradi metropolis Zooplankton Abundance Copepods Cyclops spp. ++ Sappharina sp. + Thermocyclops sp. ++ Copepodite sp. + Rotifers Brachionus pp. + Kellicottia spp. +++ Cladocerans Bosmina sp. + + = occurred sparingly + + = moderately abundant +++ = highly abundant Table 9: List of zooplankton in the Whin Estuary in the Sekondi – Takoradi metropolis ZOOPLANKTON ABUNDANCE Copepods Calanus sp. +++ Cyclops spp. + Sappharina sp. + Thermocyclops sp. ++ Copepodite sp. +++ 48 ZOOPLANKTON ABUNDANCE Rotifers Brachionus sp. +++ Keratella spp. + Kellicottia spp. +++ Trichocera sp. ++ Cladocerans Bosmina sp. +++ + = occurred sparingly + + = moderately abundant +++ = highly abundant Table 10: Richness of plankton and zooplankton genera of the three water bodies

4.4 The Benthic macroinvertebrate community