Assessments of Biological Water Quality and Condition Factor of Clarias gariepinus in Lake Alau, North – Eastern Nigeria
Umaru Buba Wakil1, Gwana Adamu Mohammed2, *, Wanas Lalai Ndirmbita1, Halima Mohammed Bala3
1Department of Fisheries, Faculty of Agriculture, University of Maiduguri, Maiduguri, Nigeria
2Laboratory Unit, Department of Animal Health and Production, Mohamet Lawan College of Agriculture, Maiduguri, Nigeria
3Department of Basic Science and Technology, Mohamet Lawan College of Agriculture, Maiduguri, Nigeria
To cite this article:
Umaru Buba Wakil, Gwana Adamu Mohammed, Wanas Lalai Ndirmbita, Halima Mohammed Bala. Assessments of Biological Water Quality and Condition Factor of Clarias gariepinus in Lake Alau, North – Eastern Nigeria. International Journal of Natural Resource Ecology and Management. Vol. 1, No. 1, 2016, pp. 1-10. doi: 10.11648/j.ijnrem.20160101.11
Received: February 28, 2016; Accepted: March 13, 2016; Published: May 9, 2016
Abstract: This study was conducted on the assessments of biological water quality and condition factor of Catfish (Clarias gariepinus) of Lake Alau, Nigeria. Water was sampled biweekly for the period of seven months from five sampling stations and was determined according to the method described by Boyd (1990). The assemblage of planktons in the Lake, it revealed that 3 genera and 10 species of zooplankton were identified; five Rotifera (66.2%), 3 Cladocera (18.2%) and 2 Copepod species (15.6%) making 100% abundance with Rotifers dominating the fauna. 4 genera and 9 species of phytoplankton were identified; 5 Chlorophyceae (60%), 2 Myxophyceae (21%), 1 Denoflugelae (10%) and 1 Bacillariophyceae species (9%) making 100% in abundance with Chlorophyceae is the most dominant taxa. Indicated that, there are adequate biological water quality parameters, within the range recommended for fish production. The Mean condition factor (K) for male’s Clarias gariepinus (raining season; 2.20 ± 0.06, dry season; 2.08 ± 0.03) and female’s(raining season; 1.90 ± 0.01, dry season; 2.2 ± 0.06). The male K was significantly higher in rainy season than in dry season, while the female K was lower in rainy season than in dry season. Clarias gariepinus in Lake Alau were in good condition in all the season. Biological water quality parameters were within the observed composition in unpolluted water bodies and found to be within the limit range for aquatic life, domestic use and for high yield for fish production. Lake Alau is maintaining its productive status and has high potential for fisheries development based on the values obtained which were in conformity with recommended values for freshwater fish production. A community based monitoring program should be developed to capture valuable data and increase awareness within the local population on water quality and shoreline issues should be encouraged.
Keywords: Clarias gariepinus, Condition Factor, Fauna, Lake Alau, Planktons, Taxa
Water is life supporting resources and the importance of water as a resource is not only tied to its quantity and availability, but also to its quality in terms of aquatic animals’ production [14,31,32]. Water system may be either static lentic; such as lake, reservoirs, etc., or flowing lotic; rivers, rainwater e.t.c, [5,6]. Fresh water quality is not constant; it varies with the time of the day, season, weather conditions, water source, soil type, temperature, stocking density, and feeding rate [5,24,31]. Virtually, water quality management must be maintained, a change in one of these factors may result in change to one or more of the other factors that have been reported to affect the quality water body [9,13,33].
In Northern part of Nigeria, numerous small and medium sized reservoirs do exist for fishing, and other purposes e.g., Lake Alau . Tabor (1992) reported that West African inshore water is rich in fish resources in quantities that can support commercial exploitation on a sustainable basis. Water quality is one of the most important compounds to the ecosystem . Better water quality is the totality of physical, biological and chemical parameters that affect the growth and welfare of aquatic organisms . A sharp drop or increase within influence the overall water quality, the aquatic animals (fish) has adverse effects on their body functions [4,5,12].
Lake Alau, which is in the northeast of Nigeria . It was created in 1987 on River Ngadda for the purpose of supplying portable water to Maiduguri metropolitan as well as for irrigating over 8000ha of farmlands in the catchment area of the reservoir (Chad Basin and Rural Development Authority, 1984). The earliest report was the preliminary study of the Fishery resources of the Lake by Odunze et al. (1995). After its impoundment, Bankole et al (2003) reported on the diversity, abundance and distribution of fish species in the Lake and identified ten fish species belonging to eight families with annual fish catch from 471.1 metric tons at low water tide to 584.9 metric tons at high water tide.
In Lake Alau, Clarias gariepinus is a common species of family Clariidae. It is a highly priced fish of considerable economic importance and available throughout the year. However, in spite of the abundance and commercial value of this species in Lake Alau, little information is available on its biological and conditional factor which is important in the production and management of the fish . Clarias species have long short body and generally cylindrical body with long dorsal fin reaching the caudal fin and they are made-up of soft ray . The fish is generally naked without scale; they have 4 pairs of un-branched barbells which some are very long and are characteristic of cat and because of these the species are referred to by the name cat fish. Clarias have accessory air breathing organ and this make them to withstand low dissolved oxygen (DO) condition and other aquatic conditions, where most other fish species cannot survive . The species is usually black or black with dark green moulting or olive on the dorsal and lateral side with white belly. Body coloration is however not a silent feature for the identification of this species, because of the ability of the fish to camouflage in environment. The head length is 30.8% of standard length with long and narrow fontanel . Africa catfish Clarias gariepinus are a very good food source for human .
To understanding Lakes biological parameters or properties, is essential to determining some of the Lakes condition and gathering information for Lake Management decisions . Water quality monitoring is an important component of Lake stewardship activities, it provides scientific basis for understanding Lake characteristics and how activities around the Lake may impact water quality, and can determine whether changes in water quality have occurred over time [1,4,31].
Lake Alau serves much purpose, such as majority irrigation, fishing as well as a source of drinking water for humans and animals especially cattle, etc. Also many depend on the resources of the water as their main sources of food and family income as a result the water is subjected to intensive use. The aim of this study is to find out the impact of biological water quality and the condition factor of Clarias gariepinus in Lake Alau. With focuses on important aspect of the biological factor (such as the phytoplankton and zooplanktons composition and distribution) as well as condition factor of Clarias gariepinus of Lake Alau.
2.1. Study Site and Location
Lake Alau is a freshwater lake in North - Eastern Nigeria. It is 19km south - east of Maiduguri, the capital city of Borno state, which is located between latitude 10º 43¹N and Latitude 10º15E and 13º17Eº . Lake Alau is the second largest lake in Borno state. The reservoir was created in 1985 by damming river Ngadda which takes its sources from Mandara Plateau. It is located between Latitude 12°N and 13°N and longitudes 11ºE and 13ºE with a total surface area of 56 km2. The reservoir was formed primarily for the provision of portable water for Maiduguri Metropolis as well as to irrigate over 8,000 hectares of farmland within and around the basin, Chad basin development authority . It has a total surface area of 56 km with three distinct seasons; a rainy season with mean annual rainfall of 600mm for July to October and a hot dry season from March to July, the dry season is preceded by a period of harmattan (a dusty, dried, cool and windy breeze blown from the Sahara desert from North Africa) between Novembers to February . The climate is Sahelian. The water volume is lowest during the months of March and April, where the great portions of the lake beds are dried, field of sand and rocks are exposed . There was neither pre-impoundment nor immediate post impoundment survey. It has a relative humidity of 49% with temperature range of 28ºC to 46ºC for both seasons. It has a maximum storage capacity of 54,600ha .
2.2. Materials Used
The standard and analytical grade materials were required and used in the cause of this scientific research study.
2.3. Methods Applied
The methods applied in study work are of the methods described by Boyd (1990); Sugunan, (2003). Standard Operation Procedures (SOP) are absolutely been observed.
2.3.1. Sampling Stations
Sampling stations were chosen after preliminary surveys of the Lake based on such factor as volume of water, accessibility and the various activities taken place in and around the Lake. Five sampling stations were marked at intervals of 1.5 to 3km to form the head region. Five landing sites were selected based on certain factors such as accessibility to the area, security and fishing activities. These stations are Abari fishing community, Daban Ali Zaki, automatic spillway, Gada and Musari landing sites respectively. These stations are;
This station is about 500 m from the bank of the lake shore where students of the department of fisheries usually conduct their practical. It is one of the landing sites that are very close to main dam.
This station is located closed to the community of Alau village. Low farming activities take place here, the water is deep and flows faster.
This station is located 500 meters away to northward of Daban Ali Zaki; farming activities such as irrigation are carried out here at small scale level.
This station is located closed to one of the Large fishing camp of fishermen; a lot of human activities are taking place in this station.
This station is the largest landing side for canoe fishermen in Lake Alau.
2.3.2. Sampling Planktons
Sampling was carried out once in a month for seven months between August, 2012 to February, 2013. Sampling was done in the morning before 9.00 AM. The composition and abundance of planktons at the five stations were determined by counting and identifying using standard identification key. Pour –through method was used to collect water at depth of about 20 cm below the water surface, poured into the plankton net, the collected plankton was carefully poured into plankton bottle, fixed with 5% formalin, corked and labelled and taken to the laboratory for further analysis.
2.3.3. Sampling Catfish
Fish were sampled from Lake Alau biweekly for the period of seven months from August, 2012 to February, 2013. Catfish were sorted among and out of the catches, transferred in to large bowl contained the Lake water, and were then transported to the laboratory for the analyses.
2.3.4. Laboratory Analyses
I. Planktons identification and counting
In the laboratory each preserved planktons sample was poured into a graduated centrifuge tube and centrifuged using a Gallen Kamp-Medico centrifuge. This was allowed to settle and the supernatant decanted. After decanting, the concentrated plankton was then analyzed by microscopic examination. A dropping pipette was used to place the concentrated plankton on a clean grease free glass slide, covered with a cover slip and viewed under microscope x10 and x40 objective lenses respectively. The planktons were counted and identified using standard identification key.
II. Catfish measurement of parameter
Standard lengths of the Fish were determined from the mouth snout to the tip of the caudal peduncle and hypural bones and weight were taken as described by Jones et al. (1999).
III. Determination of Condition Factor
Sample of 10 fish Clarias gariepinus comprises of both male and female from each station were taken for the measurement of their weight and the length to determine the condition factor using the formula below:
Condition factor is equal to the weight of catfish multiply by one hundred and then divide by the length (rest to power 3 (cube)) of the fish. This in mathematically expression implies;
Where K = Condition factor of the fish,
W = weight of the fish in grammes (g),
L3 = the length (rest to power cube) of the fish in centimetres (cm).
2.4. Statistical Analysis
The Analysis of variance (ANOVA) was used to determine differences between treatments at significance rate of P < 0.05. The standard errors of treatment means estimated. All statistics was carried out using Statistical Analysis system (SAS, 2000).
The results of the assessments of biological water quality and the condition factor of Clarias gariepinus in Lake Alau were determined and revealed the following the result and are as follows:
Table 1 shows the results obtained revealed the zooplanktons composition and abundance in all the stations. Ten species of zooplanktons were identified and these include; five Rotifera specie, three species of Cladocera and two species of Copepod. The result shows higher percentage of abundance of Rotifera with 66.22%, followed by Cladocera with 18.22% and the least in percentage of abundance recorded were Copepod with 15.56%. The genera Gladocera are 3 with the composition of Camtocercus spp (31), Chydorus spp (32) and Daphnia spp (33) with total of 96 in number of abundance with 18.22%. Copepoda (2) and the composition of Diaptomusspp (45), Metacyclopsspp (37) with a total number of 82 and that is making 15.56% in abundance. Rotifera (2), and the composition of Asplannchna spp (7), Branchionus spp (242), Caudatus spp (121), Calyciflorus spp (98) and Falcatus spp (19) with abundance of 66.22%, and totalling 7 genera, 646composition in number, and making a 100% abundance in Lake Alau.
Table 2 shows the results obtained revealed the composition and abundance in all the stations the phytoplankton of Lake Alau was made up of four genera Chlorophyceae (60%), Myxophyceae (21%). Denoflugelae (10) and followed bythe least species was Bacillariophyceae with 9% recoded respectively. Thus, the composition and the abundance of species of the genera consisted of Bacillariophyceae (1) with Naviculaspp (83) which make is 9%, Denoflugelae (1) with Euglena (92) making 10%. Chlorophyceae (5), species in this genera include; Chlorella spp(166), Closterium spp (115), Scenedesmus spp (154), Volvo spp (12) and Pediastrum spp (90)with a percentage of 60%. Myxophyceae (1) with a Aphanocapsa spp (84) and Cryptomonas spp (122) which is 21% and that a total of 1033 in abundance with a total percentage of 100% species of phytoplankton composition and abundance in Lake Alau.
Table 3 shows the mean weight (g), standard length (cm) and condition factor (mean ± standard deviation) for both seasons for Clarias gariepinus in Lake Alau. The mean condition factor for male’s Clarias gariepinus (raining season; 2.20±0.06, dry season; 2.08±0.03) was significantly higher than the females (raining season; 1.90±0.01, dry season; 2.2±0.06) in both seasons. The mean condition factor for male was significantly higher in dry season than in rainy season, while the female condition factor was higher in rainy season than in dry season.
|Genera||No. of Genera||Specie composition||Abundance||% Abundance|
|Genera||No. of Genera||Specie composition||Abundance||% Abundance|
|Sex.||Number||Raining Season||Dry Season|
|Weight (g)||SL (cm)||K||Weight (g)||SL (cm)||K|
|Male.||150||144.46 ± 0.04||18.94 ± 0.53||2.20 ± 0.06||20.29 ± 0.03||2.08 ± 0.3||2.08 ± 0.03|
|Female.||150||163.15 ± 0.03||20.29 ± 0.02||1.90 ± 0.01||132.73 ± 0.02||18.16 ± 0.01||2.2 ± 0.06|
Key: SL=standard length, K=condition factor
This is the site ‘A’ of Lake Alau showing an Engine boat was anchored during the sampling and the catches. The station is about 500 m from the bank of the Lake shore where students of the department of fisheries usually conduct their practical. It is one of the landing sites that are very close to main dam.
This is the site view of station ‘B’ of the Lake Alauwere a bridge was linked to the various farmland and the Alau villages. The station is located closed to the community of Alau village. Low farming activities take place here, the water is deep and flows faster.
This is station ‘C’ of Lake Alau choosing for the research work where all the catches were been off loaded and sampling were carried out. The station is located 500 meters away to northward of Daban Ali Zaki; farming activities such as irrigation are carried out here at small scale levels.
This is station ‘D’ where fishing activities were been taken placed and which was among the selected stations. You can some canoes were loaded with fishing net and local women came to buy the catches. The station is located closed to one of the Large fishing camp of fishermen; a lot of human activities are taking place in this station.
This is station ‘E’ of Lake Alau, where the Fishermen reside and is one of the landing site for the Fishermen loading their nets for fishing. Some sampling were been carried out in this site also. This station is the largest landing side for canoe fishermen in Lake Alau.
The extreme ecological condition of the study area especially the climatic variation could have resultant effect in modifying Lake Alau ecosystem. The water regime in this Lake was mainly influence by rainfall pattern and discharge from its tributaries. So it is expected that any variation weather seasonal or spatial in biological characteristic and condition factors of fishof Lake Alau may be influence by climatic regime and catchment characteristic i.e. extent of human activities and water volume fluctuations. Results were determined from all the five stations for the purposed of sampling and information was revealed.
Three family of zooplankton were recorded during the study period in Lake Alau, of which member of the Rotifera dominated with five species observed followed by copepods and cladocera was similar to Egborge, (1981) documentation. Ten species of zooplanktons recorded in Lake Alau in all stations and seasons were low in comparism with findings of Mohammed and Yaji (2013) in Nguru Lake in similar environments who recorded 16 species.
In the present study, all the identified species were present in all the months (season) and the stations. Low composition and abundance of zooplankton observed in this study may be attributed to many factors such as low human activities, local influences such as biological factors, e.t.c, within each seasons and as well as geographical factors as observed by Holden and Green (1960). Low composition and abundance of zooplankton could also be due to the effect of fish predation, which was found to be the major factor structuring zooplankton assemblage in several studies, In this study, zooplankton abundance was high during the dry season as a result of high primary productivity that are responsible for the high populations of zooplankton.
The phytoplankton composition of Lake Alau agreed with reports of Umaru (2014). Those blue - green algae, green algae Chlorophyceae dominate most tropical African Lakes. In this study, family Chlorophyceae dominates the fauna in respect of species number in all the months (seasons). The increased trend after the onset of rain in November shows that influx of nutrient as a result of offs favored phytoplankton. Similar observation was reported for upland and low land impoundment in plateau state by Khan and Ejike (1984). The progressive increases in the abundance of all taxa in dry seasons indicate that, dry season was favorable to phytoplankton abundance in this study, which agreed with Adeniji (1986) that dry season favor phytoplankton production. The bright sunlight and rapid tropholytic activities by the decrease in water level and the movement of the deep, nutrient rich areas into the fold of tropholytic zone, increase plankton during dry season. Increased in phytoplankton composition was not observed in December despite being dry month probably due to the North-East Trade wind (Harmattan)
The condition factor of fish indicates the relative robustness or degree of well-being of a fish. Condition factor of C. gariepinusin Lake Alau showed temporal sex variations. Higher condition factor obtained in male between August (rainy Season) and low values between Octobers. Rimmer and Merrick, (1983) obtained a similar result in Cross River, a floodplain River located at the South Eastern part of Nigeria. The results were attributed to spawning activities, which may have resulted from the accumulation of fats and ripe gonads carried by the mature adult females. The observation that 90% of the samples examined had condition factor above mean showed that the majority of fish in the population are in excellent condition. These value obtained in the present study were comparable with those documented by Adeyemo, (2011) and others. Observed variations in the condition factor could be attributable to the influence of the breeding cycle, environmental condition. Also noted that condition factor was not constant for species or population over a time interval and might be influence by both biotic and abiotic factors such as feeding regime and state of gonadal development, this is in conformity with the report of Santos and Gasper (2002). When a female catfish get sexually matured the condition factor will increased, and during spawning of the eggs, the condition factor will decreased significantly. This is in conformity with report of Batham, (1998) and William (2000) who stated that the condition factor of a fish is influenced by its age, sex, stage of maturity, fullness of the guts, types of food consumed. Relatively higher condition factor of Clarias gariepinus obtained in the present study might be attributed to desirable values of biological water quality and other factors in the lake Alau.
This study has provided information about the quality status of Lake Alau in northeast part of Nigeria and its suitability for fish production and uses. Any variation weather seasonal or spatial in biological characteristic of Lake has being influence by climatic regime and catchment characteristic i.e. extent of human activities and water volume fluctuations. Composition and abundance of planktons were studied in five stations. The studies indicated that there are adequate biological parameters in all the five stations, i.e. biological water quality parameters were within the range recommended for fish production. The zooplankton of the lake was made up of three genera, Cladocera, Rotifers and Copepod respectively. Ten species of zooplankton were identified with Rotifers dominating the fauna with five species. Nine species of phytoplankton were identified. Chlorophyceae is the most dominant taxa with five species. Clarias gariepinus in Lake Alau were in good condition in all the season.The study indicates that most of the water quality parameters were within the range for aquatic life, domestic use and fish production.
The study revealed that most of the biological water quality parameters were within the observed composition in unpolluted water bodies and also were found to be within the limit for high yield for fish production. The result of plankton study recorded the assemblage of phytoplankton and zooplankton. Chlorophyceae and bacillariophyceae were the most abundant algae in the lake throughout the study. The Rotifers were the most abundant zooplankton in the Lake. The good wellbeing of Clarias obtained indicates the Lake Alau is productive for fish production.
In general, Lake Alau is maintaining its productive status and has high potential for fisheries development based on the value obtained which were in conformity with recommended values for freshwater fish production.
Since one of the objective of constructing Alau Lake is to irrigate over 8000 hectare of farm land, Farmers should be discouraged from washing their disinfectant or herbicides spraying machine in the lake, while, household should be restricted from washing in the lake. A community based monitoring program should be developed to capture valuable data and increase awareness within the local population on water quality and shoreline issues should be encouraged. Majority of households and farmers bordering the Lake dispose both their organic and inorganic wastes into the Lake directly or indirectly and therefore, these practices should be discourage and avoided. It is recommended that the relevant stakeholder charged with management of the Lake should carry out a sensitization campaign to educate the people on the danger associated with loading of the Lake with waste (toxic) matter. Continuing routine monitoring of water quality in Lake Alau with a review of site representativeness, an increase in sampling frequency to monthly, collection of Phytoplankton samples for taxonomic identification should be encouraged.