Department of Animal Biology and Conservation Science (DABCS)

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    Assessment of Patterns of Climate Variables and Malaria Cases in Two Ecological Zones of Ghana
    (Open Journal of Ecology, 2014) Klutse, N.A.B.; Aboagye-Antwi, F.; Owusu, K.; Ntiamoa-Baidu, Y.
    Climate change is projected to impact human health, particularly incidence of water related and vector borne diseases, such as malaria. A better understanding of the relationship between rainfall patterns and malaria cases is thus required for effective climate change adaptation strategies involving planning and implementation of appropriate disease control interventions. We analyzed climatic data and reported cases of malaria spanning a period of eight years (2001 to 2008) from two ecological zones in Ghana (Ejura and Winneba in the transition and coastal savannah zones respectively) to determine the association between malaria cases, and temperature and rainfall patterns and the potential effects of climate change on malaria epidemiological trends. Monthly peaks of malaria caseloads lagged behind monthly rainfall peaks. Correlation between malaria caseloads and rainfall intensity, and minimum temperature were generally weak at both sites. Lag correlations of up to four months yielded better agreement between the variables, especially at Ejura where a two-month lag between malaria caseloads and rainfall was significantly high but negatively correlated (r = −0.72; p value < 0.05). Mean monthly maximum temperature and monthly malaria caseloads at Ejura showed a strong negative correlation at zero month lag (r = −0.70, p value < 0.05), with a similar, but weaker relationship at Winneba, (r = −0.51). On the other hand, a positive significant correlation (r = 0.68, p value < 0.05) between malaria caseloads and maximum temperature was observed for Ejura at a four-month lag, while Winneba showed a strong correlation (r = 0.70; p value < 0.05) between the parameters at a two-month lag. The results suggest maximum temperature as a better predictor of malaria trends than minimum temperature or precipitation, particularly in the transition zone. Climate change effects on malaria caseloads seem multi-factorial. For effective malaria control, interventions could be synchronized
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    Ticks associated with wild mammals in Ghana
    (Bulletin of Entomological Research, 2005-07) Ntiamoa-Baidu, Y.; Carr-Saunders, C.; Matthews, B.E.; Preston, P.M.; Walker, A.R.
    The host ranges of a collection of 21 tick species found on wild mammals in the savanna, forests and coastal zone of Ghana suggested that most species were adapted to feeding mainly on host species within a single mammalian order, i.e. on artiodactyls (bovids/suids), carnivores, rodents or pholidotes (pangolins). Only a few species were dispersed evenly across a range of orders. Seven out of ten of the most common ticks on forest mammals were significantly associated with a particular host species or a group of closely related host species, which could be viewed as their major host or hosts, but they were also recorded much less frequently on a wide range of host species. Two other species were confined to their major hosts. Only one species appeared to be widely dispersed on forest mammals and to lack a particular major host. The majority of tick species therefore occurred on hosts with very distinctive biological, behavioural and ecological characteristics. The study provided no evidence to support the view that host specificity is an artefact of sampling. Finding that the tick species on Ghanaian wild mammals occurred on particular hosts, as well as in distinct habitats, indicated that tick-host associations are important for tick survival and confirmed the importance of climate and vegetation in tick distribution. © CAB International, 2005.
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    Fisheries of two tropical lagoons in Ghana, West Africa
    (Fisheries Management and Ecology, 2004-11) Dankwa, H.R.; Shenker, J.M.; Lin, J.; Ofori-Danson, P.K.; Ntiamoa-Baidu, Y.
    The fisheries of two coastal lagoons, Keta and Songor, were studied as part of Ghana Coastal Wetlands Management Project (GCWMP) aimed at sustainable exploitation of wetland resources. Fish samples were obtained with seine nets and cast net as well as from local fishermen. Water quality parameters (pH, dissolved oxygen, temperature and turbidity) were similar in the two lagoons, except for salinity, which was significantly different (P < 0.001). Despite their close geographical proximity, the two lagoons supported different fish assemblages with the blackchin tilapia, Sarotherodon melanotheron Rüppell, and the redchin tilapia, Tilapia guineensis (Bleeker), being the most important commercial fishes in both lagoons. The number of individuals for each species in Songor Lagoon were far more abundant, with densities several orders of magnitude higher than in Keta Lagoon. However, both species were significantly larger (P < 0.01) in the latter [15-121 and 25-157 mm standard length (SL)] than in the former lagoon (30-102 and 15-95 mm SL) for S. melanotheron and T. guineensis respectively. Over-fishing, use of small-size mesh nets, limited mixing of marine and fresh water were some of the factors limiting fish production in both lagoons. © 2004 Blackwell Publishing Ltd.
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    An updated list of the ticks of Ghana and an assessment of the distribution of the ticks of Ghanaian wild mammals in different vegetation zones
    (Bulletin of Entomological Research, 2004-07) Ntiamoa-Baidu, Y.; Carr-Saunders, C.; Matthews, B.E.; Preston, P.M.; Walker, A.R.
    Twenty one species of ticks belonging to five genera of the family Ixodidae (Order Acari, sub-order Ixodida) - Amblyomma, Haemaphysalis, Hyalomma, Ixodes and Rhipicephalus (including the sub-genus Rhipicephalus (Boophilus)) - were collected from 1260 mammals, representing 29 species, 14 families and 6 orders, in four vegetation zones in Ghana during the period 1971-1978. Four other species were collected from humans in 1977. In all, eight species appeared to be new records for Ghana: Amblyomma tholloni Neumann; Dermacentor circumguttatus Neumann; Haemaphysalis houyi Nuttall & Warburton; Ixodes loveridgei Arthur; Ixodes oldi Nuttall; Ixodes vanidicus Schultze; Rhipicephalus complanatus Neumann; Rhipicephalus cuspidatus Neumann. The updated list of tick species in Ghana given here includes 41 species of ixodid ticks and four species of argasid ticks. Most species have been found in neighbouring regions of West Africa but 56 of the 121 different combinations of ixodid tick species and host species found in the collection described here have not apparently been reported before. The new combinations recorded here bring the total number of different combinations of ixodid tick species and mammalian host species now reported in Ghana to 151. The tick species found on wild mammals in Ghana mostly differed from those reported from domestic stock by other authors. The data showed that different tick species occurred in different vegetation zones and that most species displayed a pronounced preference for certain groups of related host species. Some tick species were found in the savanna feeding mainly on large bovids and/or suids; others were found in forests feeding mainly on small bovids, large rodents or small carnivores.
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    Social foraging by waterbirds in shallow coastal lagoons in Ghana
    (Waterbirds, 2003-01) Battley, P.F.; Poot, M.; Wiersma, P.; Gordon, C.; Ntiamoa-Baidu, Y.; Piersma, T.
    Social foraging in waterbirds in Ghanaian coastal lagoons was studied during October and November 1994. Two types of foraging were social: directionally synchronized flocks (often involving distinctive feeding methods used in unison) and dense pecking aggregations. Social flocks were typically larger and denser than non-social flocks, and primarily involved piscivorous birds, especially the longer-legged shorebirds and egrets. It is probable that the flocks concentrate fish into temporarily high densities through herding or confusing escape reactions. We suggest that these flocks, rather than simply forming in areas of existing high prey density, may actively enhance their foraging success. There may be a true social element to either the initiation or persistence of waterbird social foraging flocks in coastal Ghana.
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    The Muni-Pomadze Ramsar site
    (Biodiversity and Conservation, 2000-04) Gordon, C.; Ntiamoa-Baidu, Y.; Ryan, J.M.
    The Coastal Wetlands Management Project (CWMP), funded by the Global Environment Facility and implemented by the Ghana Wildlife Department, seeks to preserve the ecological integrity of coastal lagoons that serve as important sites for migratory waterbirds. This report describes the geomorphology, hydrology, soils, water chemistry, and vegetation of the Muni-Pomadze Ramsar site. Muni lagoon is a saline, shallow water lagoon separated from the sea by a sand bar which may be breached occasionally. The bulk of the rainfall in the catchment evaporates or flows as surface runoff into three streams that empty into Muni lagoon. Open water in the lagoon varies seasonally from 100 ha in the dry season to over 1000 ha in the wet season. The natural flora of the site can be divided into four main types; flood plain (including mangrove and wetland vegetation), dune vegetation, riverine vegetation, and terrestrial vegetation on elevated ground. The latter consists of a combination of grasslands, thickets, and Eucalyptus plantations. Fifty-three percent of the site is classified as natural vegetation. An additional 32.5% is agricultural land and 12.6% is residential area for the 11 communities within the site. The main source of employment are farming or fishing. The area surrounding Muni lagoon is used extensively for bushmeat hunting and as the tribal hunting grounds of the Efutu people. Apart from the global importance of the Muni-Pomadze site for biodiversity, management of the site is further justified by its considerable potential for development as an income-generating and educational nature reserve with an eco-cultural theme, managed by the local communities in partnership with the governmental and non-governmental conservation agencies.
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    Biodiversity and ecology of coastal wetlands in Ghana
    (Biodiversity and Conservation, 2000-04) Ryan, J.M.; Ntiamoa-Baidu, Y.
    Coastal wetlands are transition zones between terrestrial marine and aquatic habitats; consequently they exhibit relatively unique habitat and species diversity. Estuaries, deltas, and lagoons are among the most biologically productive but least understood ecosystems in the world. In the recent past, the world’s coastal wetlands have been drained and destroyed by conversion to agricultural land, or by industrial and urban development. Wetlands have often been overlooked or misunderstood, but scientists and coastal managers are learning that these ecosystems provide essential services. Such services include the storage of runoff, denitrification and detoxification of polluted water, prevention of shoreline erosion, and they serve as important breeding and feeding grounds for fish, shellfish, and birds. Ghana’s 550 km of coastline includes over one hundred estuaries and lagoons. These coastal wetlands are on the boundary of two major migration corridors for waterbirds: the East Atlantic Flyway and the Mediterranean Flyway. Studies by the Save the Sea Shore Birds ‐ Project and the Ghana Wildlife Society dating back to the early 1980s, have shown that significant numbers of waterbirds use Ghana coastal wetlands as staging areas and wintering grounds. At least 15 species of waterbirds occur here in internationally important populations (Ntiamoa-Baidu 1991). Five coastal lagoons and their watersheds along the Ghana coast have been proposed as Ramsar sites (internationally important wetlands) under the Convention on Wetlands of International Importance (Ramsar Convention). In 1992, the government of Ghana received support from the Global Environment Facility (GEF) for the protection of these sites (Muni-Pomadze, Densu delta, Sakumo, Songor, and Keta) under the Coastal Wetlands Management Project (CWMP), which is implemented by the Ghana Wildlife Department. The CWMP seeks to preserve the ecological integrity of these five coastal wetlands, and to enhance the socio-economic benefits that these wetlands provide to the local communities (Ntiamoa-Baidu and Gordon 1991; Piersma and Ntiamoa-Baidu 1995). To fulfil the CWMP’s goals, baseline information on the ecological health and integrity of these wetland ecosystems is required before sound management decisions can be made. Toward that end, the CWMP has implemented a series of baseline ecological studies aimed at characterizing the current status of these
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    Terrestrial birds of the Muni-Pomadze Ramsar site
    (Biodiversity and Conservation, 2000-01) Ntiamoa-Baidu, Y.; Owusu, E.H.; Daramani, D.T.
    This study was undertaken as part of the environmental baseline studies designed under the Ghana Coastal Wetlands Management Project to collect data for the description of the ecological character of selected coastal wetland sites in Ghana and provide baseline data for long-term monitoring of the sites. We provide data on the species richness, species composition, relative abundance and conservation status of terrestrial avifauna of the Muni-Pomadze Ramsar site. The terrestrial bird study was concentrated in the two reserved forest blocks, Yenku Blocks A and B within the Ramsar site. A total of 114 species belonging to 25 families were recorded. Of this, the Yenku Block A site contributed 57 species belonging to 16 avian families, while the Yenku Block B reserve contributed 91 species belonging to 24 families. The most dominant group at both sites was the Muscicapidae. Encounter rates ranged from 12.0 to 28.7 species per km and 34.7 to 141.3 individual birds per km at Yenku Block A; and 14.0 to 26.0 species per km and 45.3 to 172.7 birds per km at Block B. Mist net catch rates were 1.9 to 2.2 birds per 100 mnh and 1.8 to 4.9 birds per 100 mnh at Block A and Block B respectively. The Little Greenbul was the dominant species in the transect counts at Block A, accounting for 16% of bird sightings, and five species, Grey-backed Camaroptera, Blue-bill, Olive Sunbird, Yellow-whiskered Greenbul and Grey-headed Bristle-bill accounted for nearly 60% of the mist net captures at the site. At Block B the dominant species in transect counts was the Barbary Shrike while the Yellow-mantled Whydah dominated the mist net captures. The status of the vegetation at the sites influenced the species composition and bird communities found. The Yenku Block A site had the greatest number of forest associated species and the highest proportion of rare/uncommon bird species (10.5% of total number of species recorded). Moulting was observed in 11 species of birds and evidence of breeding activity was observed in 13 species. The site supported seven species of birds listed as wholly protected on Ghana's list of protected species and 20 biome restricted species, comprising 19 Guinea-Congo forest biome restricted species and one Sudan/Guinea savannah biome restricted species. Despite the degraded nature of the Muni forest, the terrestrial bird species richness and composition is of sufficiently high conservation value for the site to merit more effective protection and management.
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    Trends in the use of a small coastal lagoon by waterbirds: Muni Lagoon (Ghana)
    (Biodiversity and Conservation, 2000-01) Ntiamoa-Baidu, Y.; Nyame, S.K.; Nuoh, A.A.
    This paper presents data from a twelve-year (1986-98) monitoring of waterbird populations at Muni Lagoon, and discusses the ornithological importance of the lagoon and trends in the use of the site by waterbirds. The small brackish lagoon forms part of the Muni-Pomadze Ramsar site situated on the Ghana coast. A total of 48 species of waterbirds were recorded at the site comprising of 29 species of waders, eight species of terns, two species of gulls, seven species of herons and egrets, one species each of duck and cormorant. The most abundant waterbirds species recorded on the site were the Curlew Sandpiper, Ringed Plover, Greenshank, Black-winged Stilt, Common Tern, Black Tern, Royal Tern and the Sandwich Tern. Three species of waders, Black-winged Stilt, Pratincole and Little Tern were observed to breed at the site. The highest numbers of waterbirds occurred on the site in the period September to March. The site remains an internationally important wetland site by virtue of supporting internationally important numbers of four species of terns: Royal Tern, Sandwich Tern, Common Tern and Black Tern. The value of Muni lies more in its use as a feeding/staging site for migrating waders that spend the non-breeding season in Ghana or pass through to winter further south, and as a roosting site for terns which feed mainly at sea. The use of the site by waterbirds has increased by some 400% between 1986 and 1998. This is attributed to improved prey availability resulting from the opening of the lagoon into the sea during the 1994 floods, and reduced disturbance of feeding and roosting birds. This would imply that the value of the site as waterbird habitat could improve considerably with appropriate habitat management interventions and continued protection.
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    Avifauna of two upland evergreen forest reserves, the Atewa range and Tano Offin, in Ghana
    (Ostrich, 2000-03) Ntiamoa-Baidu, Y.; Asamoah, S.A.; Owusu, E.H.; Owusu-Boateng, K.
    Data are presented on the avifauna of two Upland Evergreen forest reserves in Ghana: Atewa Range Forest Reserve and the Tano Offin Forest Reserve. The data obtained for the two reserves using three survey techniques: transect counts, timed species counts and mist-netting are compared. A total of 105 species were recorded for the Atewa Range Forest Reserve while the Tano-Offin Forest Reserve yielded 110 species. Mean species encounter rate in the transect counts at Atewa was 24.2 per km while individual bird encounter rate was 52.6 per km; encounter rates at Tano Offin were 31.2 per km. and 98.2 per km for species and individual birds respectively. The most common species encountered in Atewa was the Yellow-whiskered Greenbul Andropadus latimstris (7.1% of observations in transect counts and 6.7% in spot counts), while the Green-crested Touraco (6.6% of transect counts) and Green Hylia (5.7% of spot counts) were the most abundant at Tan0 Offin. The records for Atewa included four globally threatened species while Tano yielded three threatened species. Two species of birds, the Equatorial Akalat Sheppardia aequatorialis and the yellow-bellied Greenbul Phyllastrepus flavostn’atus were recorded for the first time in Ghana from the two reserves. The bird community at Tan0 Ofin was significantly more diverse than that at Atewa. In both reserves, spot counts yielded more species (67.6% and 74.5% of total recorded at Atewa and Tan0 respectively), than transect counts and mist nets. 31 species recorded in both spot counts and transect counts at Atewa were not captured in mist nets, while nine species caught in mist nets were not recorded by the two methods. The figures for the Tano Offin reserve were 43 and six respectively. We conclude that of the three survey techniques, the timed species counts offer the most comprehensive results for rapid assessment of forest avifauna, but a combination of all three methods is necessary for complete coverage. The need for management of the two reserves to maintain their unique biodiversity in the face-of threats from mining and logging is discussed. © 2000, Taylor & Francis Group, LLC. All rights reserved.