Department of Aquaculture and Fisheries Management

Permanent URI for this collectionhttps://dspace.njala.edu.sl/handle/20.500.144402/158

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    Anthropogenic pollution impact on physico-chemical characteristics of Lake Kivu, Rwanda
    (African Scholarly Science Communications Trust, 2012-08-03) Olapade, Olufemi Julius
    Anthropogenic activities such as industrial effluent, domestic and agricultural waste disposal constitute major sources of pollution in water. The effects of these pollutants on the physico- chemical properties of Lake Kivu, Rwanda were investigated at three locations (Gisenyi, Kibuye and Cyangugu) between February 2005 and December 2006. Water samples used for physico- chemical analysis were collected from 12 stratified points on the lake. Samples collected were analysed and interpreted using appropriate international procedures. The physico -chemical properties measured were temperature, conductivity, pH, transparency, salinity, total alkalinity, dissolved organic matter (DOM), total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), nitrate – nitrogen, phosphate – phosphorus and sulphate. Mean water temperature measured (24.7 + 0.58 o C) was highest in Kibuye and lowest (24.5 + 0.31 o C) in Cyan gugu. The lake water was moderately hard with mean total alkalinity values of 88.1 ± 1.63mgL -1 ; 79.7 ± 2.36mgL -1 and 81.0 ± 2.46mg L -1 recorded in Gisenyi, Kibuye and Cyangugu respectively; salty and alkaline with mean pH values of 8.87 ± 0.07 in Gisenyi; 8.86 ± 0.06 in Kibuye and 8.91 ± 0.06 in Cyangugu. Total dissolved solids (TDS) level in the lake was above the 500mg L -1 prescribed by WHO while the mean biochemical oxygen demand (BOD) reading was within the range for unpolluted or moderately polluted lake. Water from the lake showed mineralization with mean conductivity values ranging from 1058 - 1184μS cm -1 in Gisenyi; 1058 - 1147μS cm -1 in Kibuye and 1031 - 1116μS cm -1 in Cyangugu. The mean dissolved oxygen values were below the 5mgl -1 limit recommended by WHO for fresh water fish species. SO 4- -2 and NO 3 – N concentration in the lake water does not constitute any serious health risk to both man and the aquatic organisms it supports. However, there is the need to constantly monitor the lake water to mitigate any build up of the ions to a hazardous level.
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    Challenges in Developing Aquaculture for Livelihood Enhancement in Bo City, Southern Sierra Leone
    (2023-01-15) Sumana, Sahr Lamin
    The study investigated socioeconomic characteristics, aquacultural practices and constraints among smallholder fish farmers in the study location of Bo City, Southern Sierra Leone. The present study employed a survey research design. The smallholder farmers who were growing food for themselves, for sale, and for consumption by others as well as those who were primarily growing it for the market were each given 40 questionnaires in total. The results revealed that most of the respondents were male (90.0%), married (60.0%), lacked training in fish farming (57.5%) and the household income of most (60.0%) ranged from NLe600-NLe1,000. The farmers mostly opined low fish farming experience (70.0%), Semi-intensive fish farming (67.5%), low aquaculture development (57.5%), predominantly seasonal fish pond irrigation (77.5%). All of the respondents’ view fish farming as an economically viable enterprise as well as a profitable (87.5%) entity. The mean rank of constraints was significantly (p ≤ 0.006) differed among fish farmers. The key fish farming constraints included culturing fish, fish feed in culturing fish, less interest, fewer fish farmers, high inputs, high cost of fish pond construction and intensive capital investment that could be exploited for improved productivity. The outcomes of these recent studies imply that fish farmers should receive training and funding for their operations to improve their competitiveness in their smallholder fish businesses as well as in the local and international aquaculture industries. Also, the governments and other practitioner authorities ought to implement policies and initiatives that would support fish farming activities, further research development in aquaculture, the development of the nation, and the fish farmers themselves.
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    Chemical interactions between filter-feeding mussels and Ulva prolifera: The role of dissolved organic matter and secondary metabolites in growth promotion and competition inhibition of algal species
    (Elsevier BV, 2025-09-06) Sumana, Sahr Lamin
    This review examines the chemical and ecological interactions between filter-feeding mussels and the green macroalga Ulva prolifera in integrated multi-trophic aquaculture (IMTA) systems. Mussels are crucial for nutrient recycling, as they filter water and release bioavailable compounds such as ammonium (NH 4 + ), urea (CO(NH 2 ) 2 ), and dissolved organic matter (DOM). These compounds promote Ulva growth and enhance microbial activity. In turn, U. prolifera produces sulfated polysaccharides, phenolics, and halogenated metabolites that can influence microbial communities, suppress competitors, and potentially affect mussel physiology at high concentrations. The review emphasizes the interconnectedness of nutrient exchange, DOM cycling, and microbial genes such as pmoA and mcrA, highlighting the novelty of integrating microbial ecology with biogeochemical cycles and ecosystem outcomes, illustrating both the synergies and risks present in co-culture systems. While moderate production of metabolites helps control biofouling and maintain ecosystem stability, excessive DOM or allelochemical accumulation can hinder mussel filtration and lead to hypoxia. Maintaining specific thresholds, such as DOM concentrations below 5 mg C/L and labile-to-refractory DOM ratios above 1:1, is essential for balance. This synthesis integrates microbial ecology, metabolite feedbacks, and biogeochemical processes to provide a framework for resilient IMTA design. It also emphasizes practical strategies like adjusting stocking densities, optimizing water exchange, and employing microbial monitoring tools to promote sustainable IMTA practices. By linking molecular interactions to ecosystem-scale outcomes, the review offers guidance for sustainable aquaculture systems that enhance productivity, minimize environmental risks, and improve resilience in the face of climate stress.
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    Economic Assessment of Integrated Fish Farming (Fish-Rice-Piggery) in Sierra Leone
    (Science Publishing Group, 2015) Olapade, Olufemi Julius
    The present study evaluates the profitability and environmental effect of integrated fish cum rice and piggery production at Njala University, Sierra Leone. The research carried out between June and November, 2014 consists of the pigsty (2.5m × 11m), a maggoty and integrated pond (395.2m2) sown with 0.94kg NERICA 19 rice at spacing of 20cm inter - rows and 5cm intra - rows. The pond was stocked with Clarias gariepinus juveniles (mean weight 25.6± 1.78g) at the density of 4.8fish per m2.Water quality parameters viz., temperature, pH, Dissolved oxygen, NO3-N, NH3/NH4, hardness and alkalinity were determined in the pond and were found to be within the recommended range for the culture of tropical fish. Economic analysis of the adaptive research gave a negative incremental benefit and Net Present Value (NPV) in both the first and second year of production. The sensitivity analysis evaluation shows that the enterprise is fairly sensitive to price fluctuation (-46.02%) and highly sensitive to survival rate of the fish and the scale of production of the pigs. Increasing scale of production and selling at market price will greatly enhance profitability and short term payback of costs.
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    Effect of Feeding Rate on Growth Performance, Feed Utilization, and Blood-Chemistry Indicators of Nutritional Status in Juvenile Gift Strain Tilapia (Oreochromis Niloticus L.)
    (2015) Kpundeh, Mathew Didlyn
    This study investigated the effect of feeding rates (2-10% of body weight), on the growth performance, feed utilization, and blood-chemistry indicators of nutritional status in juvenile GIFT strain tilapia, (Oreochromis niloticus) initial weight 72.73±0.15g. The 56 day trial conducted in cages tested five groups, with three replicates each. Fish were fed twice a day. Data were analyzed using one way ANOVA. Results showed that final body weight, food conversion rate (FCR), weight gain, specific growth rate (SGR), protein retention efficiency (PRE), protein efficiency ratio (PER), feed intake, and condition factor (CF) were significantly affected by the feeding rates (P 0.05). Serum indicative parameters of liver-enzyme functions and food metabolism, including blood glucose (GLU), triglyceride (TG), total protein (TP) levels, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) enzyme activities were assayed. Blood glucose level of the fish was significantly affected by the feeding rates (P 0.05). Feed provided at a rate of 2%-10% of body weight may meet physiological wellbeing of GIFT strain tilapia, however growth performance and other endocrine functions (IGF-I) are affected by lower and higher feeding rates. Our findings could be very useful to tilapia farmers.
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    Environmental and Economic Impact of Fish cum Rice and Poultry Production Integration System
    (2015-04-14) Olapade, Olufemi Julius
    The economic viability and environmental friendliness of integrating fish with rice and poultry was evaluated in a fish pond (520m 2 ); a paddy platform (8 x 25m 2 ) sown with 1.00kg NERICA 19; a poultry house (3.5 x 11m in dimension) and a maggoty. Integrated pond was stocked at 1.923 fish per m 2 (25g mean weight) while 400 day-old broilers were housed. Water quality parameters determined were within recommended range for the culture of tropical fish species and statistically non-significant (p < 0.05). The synergy gave positive Net Present Value NPV of Le 18,520,661.51 (US\$4,161.95) in the third year; a benefit-cost ratio of 1.23 and two year payback. Sensitivity calculated was 23.6% an indication of the sensitivity of the investment to survival rate. Integrating fish with rice and poultry is environment friendly, and economically viable with potential to create employment, augment income and improve the living standard of sub Saharan poor population.
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    Growth Performance and Hematology of the African Catfish ( Clarias gariepinus Burchell, 1822) Juveniles Fed Graded Level of Anisophyllea Laurina R. Br. Ex. Sabine ( Monkey Plum ) Seed Meal
    (2015-04-14) Olapade, Olufemi Julius
    Anisophyllealaurina seed meal (ASM)in this study partially replacedfish meal(FM). Isonitrogenous and isocaloricdiets (40% crude protein) containing0%, 25%, 50%, 75%, 100% ASMwere formulated. Clariasgariepinus juveniles (32.72 ± 0.32) stocked at 10 fish/50L troughs fed twice daily for 98 daysutilized effectively the formulated diets for growth.Mean weight gained (MWG) washighest at 0%and 25% butdecreased as ASM increased.Specific growth rate (SGR), Protein efficiency ratio (PER), Protein intake (PI) were significant (p<0.05) at 0% and 25% inclusion. Survival rate (%SR)was unrelated totreatment - highest at 0% and 100% (97%SR)and least at 75% (90%SR).Carcass protein, packed cell volume and haemoglobin counts were statistically the same at 25%, 50%, 75% and 100% inclusion. Since C. gariepinusperform better at 25%ASM inclusion it is recommended as the level of replacement for FM in fish diets.
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    Harnessing light: innovative photodynamic therapy for controlling Aeromonas hydrophila in aquaculture
    (Springer Science+Business Media, 2025-02-28) Ayana, Gelana Urgesa
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    How Grouping Data over Time Can Hide Signs of Stock Status: A Case Study Using LBSPR on Frigate Tuna (Auxis thazard, Lacépède, 1800) in the Northeast Atlantic Ocean
    (Multidisciplinary Digital Publishing Institute, 2026-01-23) Bayon, Mustapha Sly
    Length-based stock assessment methods are widely applied in data-limited fisheries, yet the effects of how length-frequency data are temporally grouped prior to analysis remain poorly examined. Temporal grouping is routinely used to increase sample size and approximate equilibrium conditions, but it may also alter the size structure presented to assessment models and bias inference. In this study, we evaluate how alternative temporal grouping schemes influence stock status inference within a single length-based framework, using the length-based spawning potential ratio (LBSPR) model as a diagnostic tool. Using a 30-year length-frequency dataset from a tropical purse seine fishery in the Northeast Atlantic as an illustrative case, we applied LBSPR under four practice-relevant temporal grouping schemes: full-period pooling, a broad regime-based scheme, decadal blocks, and five-year blocks. Life history parameters and model settings were held constant across schemes to isolate the effect of temporal grouping. A sensitivity analysis of biological parameters was conducted for the finest temporal scheme to contextualise robustness. Results show that temporal grouping alone can substantially alter the inferred status of the illustrative case. The fully pooled scheme produced an apparently favourable status signal, whereas finer temporal groupings revealed extended periods of inferred reproductive depletion, followed by a more recent recovery. Sensitivity analyses indicate that, while biological parameter uncertainty influences the magnitude of estimates, it does not overturn the dominant effect of temporal grouping on inferred status patterns. This study demonstrates that temporal grouping is not a neutral preprocessing step but a structural decision with the potential to conceal or reveal exploitation signals in length-based assessments. We argue that temporal grouping should be treated as an explicit sensitivity dimension in data-limited assessment workflows. By shifting attention from stock-specific outcomes to data-structuring choices, this work provides practical guidance for improving transparency and robustness in length-based stock status inference.
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    Influence of net cages on water quality and trophic status of Lake Victoria, Kenya: The case of Kadimu Bay
    (Wiley, 2023) Mawundu, Sellu
    Water quality is a critical component regulating ecosystem functioning in aquatic habitats, requiring regular monitoring for sustainable ecosystem services. Cage fish farming has the potential to affect water quality because of its rapid increase in many African waterbodies in response to dwindling wild fish stocks. Thus, there is a need for more studies to guide sustainable cage aquaculture in African lakes and reservoirs. This study evaluated the possible effects of cage farming of Nile tilapia (Oreochromis niloticus) on water quality parameters and the trophic state of Kadimu Bay, Lake Victoria, Kenya. Sampling for physicochemical and biological variables, including nutrient load, was conducted from January to October 2021, at five fish cage sites and a control site within the bay. In situ measurements of physical variables were undertaken in the field, while analysis of water samples for nutrient loads, biological and chemical variables was undertaken in the laboratory, following the methods described in APHA (American public health association standard methods for the examination of water and waste water. APHA‐AWWA‐WEF, 2005). The Carlson's Trophic State Index (CTSI) was used to classify the trophic state of the cage sites, while the total nitrogen:total phosphorus (TN:TP) ratio was used to determine the primary productivity limiting nutrient in the bay. The study results indicated electrical conductivity was significantly lower at the control (97.53 ± 4.17 μS/cm), compared to cage sites (105.42 ± 5.32 μS/cm at the Utonga cage site to 112.84 ± 1.94 μS/cm at the Oele cage site), indicating water of relatively lower quality at the cage sites. Similarly, the nitrite concentrations were higher at cage sites (6.35 ± .96 μg/L at the Uwaria cage site to 3.16 ± 2.25 μg/L at the Utonga cage site), and lower at the control site (2.68 ± 1.39 μg/L). In all, 14 physicochemical variables did not vary significantly between the cage and control sites, with nine variables (temperature, turbidity, electrical conductivity, total suspended solids, particulate organic matter, chlorophyll‐a, TP, nitrate and TN) being within the recommended thresholds for aquatic life processes. The bay was evaluated as being in a light eutrophic state, indicating moderate influence of the fish cages on the trophic state of the sites. There was a moderate relationship between chlorophyll‐a and TP concentration at the sampling sites (R2 = .50), compared to a stronger relationship with (R2 = .78). The TN:TP ratios were <10 at the sampling sites, indicating nitrogen was the limiting factor for primary production in the bay. The calculated CTSI suggests that the bay exhibited a light eutrophic state. Overall, although the results of this study showed cage aquaculture is not a current challenge to the water quality of the bay, regular monitoring is nevertheless recommended to inform sustainable aquaculture development in the bay and lake.
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    Lengthz-Weight Relationship and Condition Factor of Coelotilapia joka (Thys van den Audenaerde, 1969) in the Rokel/Seli River, West Africa
    (SciPress Ltd., 2020) Konoyima, Komba Jossie
    This study was conducted in the lower, middle and upper reaches of the Rokel/Seli River, Northern Sierra Leone. There is a research gap on the growth or wellbeing of tilapia fish species in Sierra Leone. The objective of this study is to determine the length-weight relationship and condition factor of Coelotilapia joka from the main river channel. This research could contribute to promoting an agenda for fish culture practices for the fish. A total of 228 specimens of Coelotilapia joka were collected using gill nets. Fish length and weight measurements were done using fish measuring board and digital weighing balance respectively. Measurement for water quality was made using the Jemway multi-parameter water quality measuring device (Model: J970, Barloworld Scientific, United Kingdom). The values for regression coefficient “b” gave 2.5437, 2.1841 and 2.4585 for males, females and combined sex respectively, implying a negative allometric growth in the fish at (b 1). The difference in ‘K” for both sex is significant (p<0.05). A study for a period of one year could, however, provide a complete analysis of seasonal variations in growth and condition of the fish.
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    Nutritional Evaluation of Defatted Groundnut Cake meal with Amino acid as Protein Supplement in African Catfish (Clarias gariepinus Burchell, 1822) Juveniles Diet
    (2018-12-15) Olapade, Olufemi Julius
    Background and Objective: Fish feed constitute about 60% of fish production costs and this is because fishmeal (FM) which is the major protein feedstuff in fish feed is in excessive demand by other agricultural production sectors thus leading to increase in its price.Researching into alternative way of attenuating FM in fish feed production becomes necessary.Consequently, in this paper, the effect of feeding Clarias gariepinus juveniles with diets supplemented with defatted groundnut cake (DGNC), lysine (L) and methionine (M) was studied for 56 days.Materials and Methods: Fish of an initial mean body weight of 34.4±0.548g were fed the trial diets at inclusion levels of 0, 25, 50, 75 and 100%.The diet with 0% DGNC and 100% fishmeal served as the control.The experimental fish held in 56 L troughs were fed treatment diets in triplicate group of 20 fish per replicate at 5% body weight twice daily.Water parameters measured according to standard methods were pH, temperature, conductivity and NH 3 .Dissolved oxygen was not determined because the experiment was completely flow-through.Results: At the end of the feeding trial, fish fed with the control diet recorded the highest mean weight gain (17.33±1.53),followed by fish fed diet 2 (14.33±0.58).Protein intake and survival rate were not significantly different (p<0.05) but protein efficiency ratio was significantly different among dietary treatments.Feed Conversion Ratio (FCR) was highest at diets 1, 2 and 3, respectively and were not statistically different (p<0.05).The water quality parameters monitored in the trial were within recommended range and were not affected by the supplemented diets.Conclusion: It can be concluded that, substituting FM with DGNC, L and M at 25 and 50% inclusion will not compromise growth performance and feed utilization of the fish and neither will it significantly lower the water quality of the culture environment.
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    Occupational hazards, risk and injuries of fish processors in Tombo a coastal fish landing site, Sierra Leone, West Africa
    (Academic Journals, 2021-06-30) Olapade, Olufemi Julius
    Fish and fish products bear potential hazards and risks of public health concern. A preliminary study of hazards, injuries and risks among fisherfolk in Tombo, Sierra Leone, West Africa was carried out on November 2018. Sixty subjects from among the organized fish processor groups were interviewed with semi-structured questionnaire. Results obtained from the study were analyzed with Microsoft Excel and presented in tables and charts. The results of the study indicated that females (56.7%) were more involved in fish processing than males (41.7%); and the active age of these processors fell in the age range of 35-45 years. Married people (71.7%), dominated singles, widowed and divorced put together. Dominant religion in the study area was Islam and Christianity. Smoking (hot and cold), frying, packing, icing, filleting, seasoning or the combination of two or more according to the subjects was the prevailing processing methods used by processors in Tombo. Inherent hazards, injuries and risks reported by the respondents included high blood pressure, cardiovascular disease, nervous tension, insomnia, skin disease, bronchitis or asthma, muscular problems or those of the joint, long-term neck and back pains, eye problem, typhoid, malaria, and hearing problem caused by environmental noise. To mitigate the hazard and risks associated with fish processing in Tombo, training on appropriate fish handling and processing techniques; the provision of appropriate handling and processing equipment by responsible stakeholders were considered according to the subjects rational options. Key words: Occupation, hazards, injuries, risks, fish processors, Tombo, Sierra Leone.
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    Overexploitation and urgent need for precautionary management of Bonga Shad ( Ethmalosa fimbriata ) in West African waters: A multi‐model Bayesian assessment
    (Wiley, 2026-07-30) Konoyima, Komba Jossie
    Ethmalosa fimbriata, a key small pelagic species underpinning food security and livelihoods along the West African coast, warrants a robust stock assessment due to concerns of overexploitation. This study synthesizes multi-fleet catch records (1970-2021) and unstandardized catch per unit effort (CPUE) data (1995-2017) from the Eastern Central Atlantic (ECAO) to evaluate the northern stock using four surplus production models: the catch-only (CMSY) and abundance-only (AMSY) maximum sustainable yield models, the Bayesian state-space model (BSM) and the Just Another Bayesian Biomass Assessment (JABBA) model implementing Schaefer, Fox and Pella-Tomlinson functions. The objective was to evaluate model predictive accuracy and stock status to provide evidence-based management advice. From the results, CMSY indicated 2021 biomass (B) was marginally above the sustainable limit (B/BMSY ≈ 1.03) with current fishing mortality (F) near FMSY, while AMSY and BSM both indicated ongoing depletion (B/BMSY ≈ 0.56-0.81) and overfishing (F/FMSY >1.0). JABBA's Schaefer model, demonstrating superior fit (root-mean-square error = 16.9%, Deviance Information Criterion = -382.7) over Fox and Pella-Tomlinson models, estimated 2021 biomass at 9% below BMSY and fishing mortality at 59% above FMSY. Fox and Pella-Tomlinson models yielded similar biomass trajectories but were less precautionary. Projections indicate that only Schaefer-based total allowable catches (TACs) below 100,000 t would stabilize biomass; higher quotas risk continued decline. Despite limitations including incomplete catch data and reliance on unstandardized indices, results underscore the urgency for precautionary catch limits, regional coordination and improved compliance to ensure sustainability. This study offers a transferable assessment framework for data-limited fisheries and supports evidence-based policy for the conservation of E. fimbriata and food-security resilience in West Africa.
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    Sex ratio, gonad maturity and size-structure of Pagelus bellotti in Sierra Leone
    (2021-02-16) Mansaray, Alie Hindolo Dembeh
    A total of 135 specimens of Pagellus bellotti were randomly collected from artisanal boats in August 2018. Study of sex ratio, gonad maturity and size-structure of Pagellus bellottii is meagre in Sierra Leone, and forms the basis of the present study. The study will contribute to current knowledge and promote rational exploitation of the stock. Length and weight were measured using a fish measuring board (cm) and digital weight scale (g) respectively. Sex and gonad maturity were macroscopically assessed. Results showed dominant males (71.9%) and significant difference observed (1:2.6) and expected (1:1) female: male sex ratios (p 0.9). Indexes of condition were greater than 1.0 (K > 1) for all sex categories. Results portrayed a heterogeneous gender population of Pagelus bellottii and vast similarity in reproductive strategies by both sexes. The fish comprised of one size group and males may be growing larger than the females. Growth pattern was near-isometric for females and negative allometric for the males, and both sexes were in better condition (K >1.0). An annual study could provide further insight.
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    The length-weight relationship, condition factor and reproductive biology of Pseudotolithus (p) senegalensis (valenciennes, 1833) (croakers), in Tombo western rural district of Sierra Leone
    (African Scholarly Science Communications Trust, 2014-11-19) Olapade, JO
    The length – weight relationship (LWR), condition factor (K), sex ratio, gonadosomatic index (G S I) and hepatosomatic index (H S I) of 412 specimens of Pseudotolithu s s enegalensis (Valenciennes, 1833) from Tombo , a coastal fishing community in the western rural district of Sierra Leone were studied for twelve months . Samples used for the study were collected from the catches of artisanal fishers and measurement s of length and weight of samples were done in situ using the facilities of the Ministry of Fisheries and Marine Resources. Samples for the reproductive study were preserved in an ice box and taken to the laboratory of the Department of Aquaculture and Fisheries Management, Njala University , Sierra Leone for analysis. The parameters "a" and "b" of the length - weight relationship were estimated using the equation described by Ricker ( W = aL b ) while the condition factor was calculated using Fulton\`s equation (K = W1 00 / L 3 ) . The reproductive biology of the fish was estimated using Gonadosomatic index ( GSI ) and Hepatosomatic index ( H S I ) . The combined LWR for both sexes showed that a, b and r values were – 2.57 , 3. 3 5 and 0. 899 , respectively. The r – values obtained show a strong linear relationship between the length and weight of the species. The length - weight relationship indicated allometric growth for P . senegalensis in the study area. The condition factor (K) varied from 0.64 – 1.0 ; this may be attributed to environmental conditions of the water . The species clearly exhibited a positive allometric growth pattern ( tα ( 2) , 0.05, 411 > 1.965) . The sex ratio of males to females was 1:1. 15 and was not significantly different from the expected 1:1 ratio. Estimation of GSI and HSI was carried out from December, 2010 to May, 2011 to determine the spawning behaviour of P. senegalensis . The mean GSI obtained indicate d that March and April , respectively are the two peak spawning period for the species . Gonado somatic index ranged between 1.1 % and 2.8% for the females. The results of this study revealed that P. senegalensis doe s not have obligatory spawning month but exhibit multiple spawning behaviour. T he length - w eight relationships and condition factor of the study indicated that the fish were thriving very well in the coastal water of Sierra Leone. Sustainable management of the species , therefore , require s that the environment be protected against anthropogenic pollution and imposition of closed fishing season especially during the t wo peak spawning period is recommended to enable the species recruit effectively.