{"title":"Food and Feeding Habits of the Guppy, Poecilia reticulata , from Drainage Canal Systems in Lagos, Southwestern Nigeria","authors":"J. Kombiok, S. Buah, I. Dzomeku, H. Abdulai","doi":"10.4314/WAJAE.V20I2","DOIUrl":"https://doi.org/10.4314/WAJAE.V20I2","url":null,"abstract":"The food and feeding habits of the Guppy, Poecilia reticulata , from drainage canal systems in Lagos Metropolis, Nigeria, was investigated over a period of 24 months. Fish samples were collected monthly from 15 study sites. A total of 2400 fish stomachs were analyzed using the numerical and frequency of occurrence methods. P. reticulata fed mainly on algae, organic detritus, diatoms, mosquito larvae parts, protozoan, zooplankton and fish parts while algae form the most abundant and important food item, constituting 79.03% of food items by numerical and 33.17% by occurrence of stomachs examined. Amongst the algae, Ulothrix sp. was the most preferred, constituting 33.17% by numerical and 20.82% by occurrence. The least eaten food item was fish parts constituting 4.46% by numerical and 1.19% by occurrence. There was a significant difference (P 0.05) in the number of other food items consumed for both seasons. However, by occurrence method there was no significant difference (P > 0.05) in food items consumed for both seasons. The three size classes of P. reticulata exhibited similar food habits with the presence of eight categories of food items in their stomachs. The largest size class ate more of algae, organic detritus and fish parts, followed by the medium size class while the small size class ate less of these food items. The species is an opportunistic benthopelagic omnivores, whose preference for food fluctuates with season, with a peak in diversity of food types occurring in the rainy season.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"20 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V20I2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70685943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Species Diversity and Relative Abundance of Fisheries Resources Found in Beach Seine along the Central Coast of Ghana","authors":"G. Foli, P. Nude, Chiri G. Amedjoe, L. Kyei","doi":"10.4314/WAJAE.V20I1","DOIUrl":"https://doi.org/10.4314/WAJAE.V20I1","url":null,"abstract":"The diversity and relative species abundance of fisheries resources were studied from Winneba to Cape Coast on the central coast of Ghana during December 2007 to May 2009. Samples of organisms were collected at random from beach seine landings during the study period. The fishes were counted and identified to the family and species levels. Ecological indices such as Shannon-Wiener diversity index, equitability and Sorenson’s similarity index were used to analyse the data. Specimens from Winneba, Saltpond and Cape Coast comprise 56 species belonging to 30 families. Carangidae, Haemulidae, Clupeidae and Sciaenidae were some of the families, where key species occurred during the study. The relative abundance of key organisms in the beach seine landings include Chloroscombrus chrysurus (26.0%) in 2007, Brachydeuterus auritus (22.8%) in 2008, Ilisha africana (14.7%) in 2008, Sardinella aurita (13.1%) in 2009 and Selene dorsalis (11.2%) in 2007. The organisms that were in low relative abundance were Acanthurus monroviae, Penaeus notialis, Galeoides decadactylus and Trichiurus lepturus . Shannon-Wiener diversity index, estimated in the study, ranged from 2.54 to 2.83. Species equitability range was 0.67–0.77, and the Sorenson’s similarity estimated ranged was 0.66–0.69. The estimations of fish species diversity and equitability were higher (H’ = 2.83; J’ = 0.77) during the 2009 study in the central coast of Ghana. The similarity indicators in the various paired periods during the study showed considerable similarity in the organisms that were exploited by the beach seine in the area. The study explains the linkage between the diversity and relative species abundance of the coastal fisheries resources and offshore marine resources in Ghana, and the need to regulate beach seine operations in order not to over exploit the juvenile stocks.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"20 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V20I1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70685524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impact of Land Use on River Systems in Ghana","authors":"J. Ayivor, C. Gordon","doi":"10.4314/WAJAE.V20I3","DOIUrl":"https://doi.org/10.4314/WAJAE.V20I3","url":null,"abstract":"Rivers play significant roles in the provision of water for domestic and industrial purposes. Nevertheless, land use dynamics continue to impact on river catchments which have negative repercussions for river health. This study focuses on land use change in the Okyeman Traditional Area, which encompasses three major river basins namely, the Densu, the Birim and the Ayensu. The study was aimed at investigating causes and impacts of land use change within the three river catchments and how these impacts could be curtailed to safeguard river health and sustainable water supply. Data for the study was derived from analysis of remotely sensed Landsat 7 ETM satellite imagery, and from questionnaire administration. Additional information was culled from the existing literature on land use, land use change, land cover change and related subjects. One major finding was that most of the river basins have undergone massive transformation over the last three decades as a result of various land use activities. The dominant land use types in the basins presently are agriculture, urban development, grazing, residential and transportation and fishing. The study also revealed that mining, indiscriminate waste disposal, water extraction and deforestation for fuel wood and other domestic uses, excessive use of chemical fertilizers and land degradation due to improper agricultural practices are also major land use activities that impact negatively on the river systems. The study concluded that there is the need to streamline land use activities, conserve vital ecosystems like watershed areas and maintain buffers along stream channels as a matter of policy to ensure adequate protection of aquatic fauna and to ensure sustainable water supply.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"20 1","pages":"83-95"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V20I3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70685686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Water sorption isotherm characteristics of seeds of six indigenous forest tree species in Ghana","authors":"J. M. Asomaning, M. Sacande, N. S. Olympio","doi":"10.4314/WAJAE.V18I1.70312","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70312","url":null,"abstract":"The relationship between storage temperature, relative humidity and seed water content was investigated for six indigenous forest tree seed species, namely Garcinia kola , Terminalia superba , Terminalia ivorensis , Mansonia altissima , Entandrophragma angolense and Khaya anthotheca in Ghana. Seeds were equilibrated over a series of lithium chloride solutions with relative humidities ranging from 12 to 93% and silica gel with relative humidity of 3% at 20 oC. Seeds reached equilibrium with different days depending on seed size and structure, ranging from 13 days for E. angolense to 91 days for G. kola . When seeds equilibrated, moisture contents were determined gravimetrically, and values of moisture contents were then plotted against relative humidity to construct moisture sorption isotherms for the species. Seeds of T. superba , T. ivorensis , M. altissima , E. angolense and K. anthotheca , exhibited a sigmoidal relationship between seed water content and relative humidity indicative of three regions of water binding. Contrarily to other reports, the shape of the isotherm curve for G. kola – a desiccation sensitive species – also showed the reversed sigmoid pattern similar to isotherm curves of orthodox species rather than the monotonic shape. The isotherms showed that seed moisture content increased with increasing relative humidity. Seed samples of G. kola , placed at all relative humidities chambers, lost water(desorption) as the initial water content of 58% was very high and, therefore, possessed a higher water potential than the environments. Seeds of the other species either lost water (desorption) to the relative humidity chambers, or absorbed water from the chambers depending on the relative humidity of the environment they were placed.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"31 1","pages":"15-28"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70312","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70694092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Distribution of the Enzyme Arginase in the Tissues of Selected Cichlidae Species: Tilapia zillii, Sarotherodon galilaeus and Oreochromis niloticus","authors":"R. Okonji, M. Popoola, O. Komolafe, A. Kuku","doi":"10.4314/WAJAE.V18I1.70318","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70318","url":null,"abstract":"The paper reports the tissue distribution of the enzyme arginase in three different Cichlids: Tilapia zilli , Sarotherodon galilaeus and Oreochromis niloticus , from the Aiba and Osinmo reservoirs, located in the southwestern Nigeria. The tissues of S. galilaeus showed very high activity of arginase as compared with the other two species. The liver of O. niloticus and the gut of T. zillii showed very high activity of arginase in the Osinmo reservoir. The high arginase activity observed in the tissues of these organisms is attributed to ureotelism and is similar to the result obtained for tilapia, Alcolapia grahami , from lake Magadi, Kenya.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"18 1","pages":"47-52"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70318","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70693644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Sediment Discharges from Ghanaian Rivers into the Sea","authors":"S. Akrasi","doi":"10.4314/WAJAE.V18I1.70320","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70320","url":null,"abstract":"Information on sediment yield of a river basin is an important requirement for water resources development and management. In Ghana, data on suspended sediment yield are limited owing to lack of logistic support for systematic sediment sampling activities. The paper presents the results of a study, using measurements of suspended sediment transport for 21 monitoring stations in southern Ghana to develop simple predictive models for suspended sediment yields of catchments for which no sediment measurements had been undertaken. Regression analysis was used to establish a relationship between specific suspended sediment yield and both the mean annual runoff, and the drainage basin area. One of the prediction models was used to estimate the sediment loads of the southern Ghana rivers and total suspended sediment discharges into the sea, in addition to specific suspended sediment yields from the drainage basins. The specific suspended sediment yield for the south-western and coastal basin systems ranged between 11 and 50 t km –2 year –1 . The annual sediment discharges into the sea by the rivers ranged between 15,000 and 1.2 × 10 6 t, and total yearly sediment discharge into the sea by Ghanaian rivers is estimated to be 2.4 × 10 6 t.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"18 1","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70320","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70693695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Some Physicochemical Charateristics of Badagry Creek, Nigeria","authors":"S. Akintola, M. Anetekhai, E. Lawson","doi":"10.4314/WAJAE.V18I1.70313","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70313","url":null,"abstract":"Badagry Creek runs through Nigeria and Republic of Benin with access to the Atlantic Ocean. Physicochemical parameters of the creek were studied from 2003 to 2004 to generate baseline data in view of its increasingly importance in economic life and developmental issues. Two important sites, with highest human activities, Akarakumo and Topo, were chosen for monthly analyses of water samples following methods and procedures of APHA. Colour, surface temperature, pH, salinity, turbidity, phenol, dissolved oxygen, biological oxygen demand, conductivity, total suspended solids, total dissolved solids, total hardness (calcium and magnesium), nitrates, phosphates, sulphates, chlorides, free carbon dioxide, acidity, oil and greese were analysed. There were significant difference in monthly variations (P 0.05). The mean concentration of the parameters showed significant variation with mean values of 27.51 ± 1.17 °C for temperature, biological oxygen demand 18.38 ± 8.14 mg/l, free carbon dioxide, 4.00 ± 2.07 mg/l and ammonia 0.18 ± 0.15 mg/l. Values were within those reported for most estuaries globally. It was revealed that variations in the water quality of the creek are largely influenced by season and intrusion from the ocean at different tide levels.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"18 1","pages":"95-107"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70313","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70693976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impact of Cypermethrin on Selected Enzymes in Tissues of Heterobranchus bidorsalis","authors":"U. Gabriel, I. Jack, E. Egobueze, E. Os","doi":"10.4314/WAJAE.V18I1.70315","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70315","url":null,"abstract":"Heterobranchus bidorsalis (mean total length 31.50 ± 2.32 cm SD; mean weight 241.25 ± 30.39 g SD) was exposed to cypermethrin (0.005, 0.0075, 0.010, 0.125 and 0.0150 p.p.m.) for 23 days to determine the activity of transaminases (alanine transaminase, ALT; aspartate transaminase, AST) the phosphatase, alkaline phosphatase, ALP in the gill, kidney, liver and muscle tissue. The activity of ALT in the gill at 0.005 and 0.010 p.p.m. were lower (P > 0.05) than the control, whereas elevated activity above the control were recorded at the other concentrations. AST activity was excited 11.36–220.45% above the control value at all the concentrations. ALP activity was inhibited below the control value with the highest inhibition, 40.46% at 0.010 p.p.m. ALT activities in the kidney at all the exposure concentrations were elevated 33.33% and 66.67% above the control at 0.005–0.010 p.p.m. and 0.0125–0.0150 p.p.m., respectively. Inhibition below the control was recorded in all the exposure concentrations for AST and ALP. ALT and AST activities in the liver were inhibited below their respective control values. ALP activity was inhibited at 0.0075 and 0.0150 p.p.m. (44.12 and 23.53%, respectively, below control value), but excited at the other concentrations with a peak, 33.83% at 0.010 p.p.m. In the muscle, 12.68% and 23.94% elevation above the control were recorded at 0.0125 and 0.0150 p.p.m., respectively, for ALT with a decrease in the lower concentrations. There was excitation of AST activity at 0.0050, 0.010 and 0.015 p.p.m., and inhibition at 0.0075 and 0.0125 p.p.m. relative to the control value. There was general inhibition of ALP activity in the muscle of treated fish below the control except at 0.010 p.p.m. The usefulness of the enzymes as biomarkers of cypermethrin toxicity appeared to be concentration and tissue dependent, and can be effectively used to assess the impact of the agrochemical on the fish.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"18 1","pages":"121-127"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70315","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70694026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Observations on the Composition, Physiological Condition and Fisheries in Erinle Lake, Osun State, Nigeria","authors":"O. Komolafe, G. Arawomo","doi":"10.4314/WAJAE.V18I1.70317","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70317","url":null,"abstract":"The level of fish production in Nigeria is far less than the current fish demand. The study, therefore, on fish composition and fishing activities in Erinle Lake is meant to suggest means of bridging the gap between fish supply and demand in the country. Fish samples were obtained from gill-net, cast net and traps. Ten families of fish comprising 19 species were identified, dominated by Cichlid fish (71%) largely made up of Sarotherodon galilaeus (42%). The sex-ratio of most fish in the lake tends to unity (1:1), suggesting reproductive stability. Condition factors are high for the fish species – an indication that they thrive well in the habitat. Key water quality parameters such as pH, DO, etc. were found to be favourable for survival and thriving of food for some fish species. Fishermen on the lake used 2.54 cm mesh size net contrary to 7.62 cm mesh size recommended in Sea Fishing Regulations of 1971, which is a supplement of Nigerian Sea Fisheries Decree (ACT) of 1971. As a result the lake had been exploited of fish resulting in a low and small size catches. It is recommended that the fisheries be closed during the peak spawning period to allow possible recovery. Also, strict monitoring control and surveillance of the lake is highly recommended, most especially in the use of unapproved fishing nets and methods.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"18 1","pages":"71-78"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70317","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70693633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Osae, M. Cobblah, F. Djankpa, E. Lodoh, P. Botwe
{"title":"Development of a Bait System for the Pharaoh’s Ant, Monomorium Pharaonis L. (Hymenoptera: Formicidae)","authors":"M. Osae, M. Cobblah, F. Djankpa, E. Lodoh, P. Botwe","doi":"10.4314/WAJAE.V18I1.70316","DOIUrl":"https://doi.org/10.4314/WAJAE.V18I1.70316","url":null,"abstract":"The infestation of the Pharaoh’s ant, Monomorium pharaonis L. is widespread and, sometimes, very serious in homes, hospitals, restaurants, factories, etc. People are helpless because effective baited traps are not available locally, and little has been done locally to develop effective control strategies for these ants. The study aimed at developing an appropriate bait system from local materials for the control of the Pharaoh’s ant. Nine baits and three insecticides were evaluated in the laboratory and field situations. Groundnut cake, dry fish and granulated sugar were the most attractive baits. Rimon (a Benzoylphenyl urea), an insect growth regulator, was the most promising insecticide for incorporation into the bait system. It is, therefore, recommended that a bait system, containing groundnut cake, sugar and dry fish, mixed with 1% Rimon, be evaluated for Pharaoh’s ant control.","PeriodicalId":39286,"journal":{"name":"West African Journal of Applied Ecology","volume":"37 1","pages":"29-38"},"PeriodicalIF":0.0,"publicationDate":"2011-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4314/WAJAE.V18I1.70316","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70694036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}