African Journal of Fisheries Science

African Journal of Fisheries Science Vol. 2 (4), pp. 090-095, April, 2014. © International Scholars Journals

Full Length Research Paper

Capital based fisheries administration of chambo (Oreochromis spp.) fish stock of Lake Malombe in Malawi

Mitawa Mtumiki, Rashid Matita and Wyson Haba

Department of Agriculture, Faculty of Fishery, Mzuzu University Northern Region, Malawi.Email:[email protected]

Accepted 16 March, 2014

Abstract

A study to establish bioeconomic options for economic exploitation of Chambo (Oreochromis spp.) fisheries of Lake Malombe was conducted between 2010 to 2012. Three models, logistic regression, Univariate Autoregressive Integrated Moving Average and Gordon Schaefer bioeconomic models were used in the analysis. Primary qualitative and quantitative data from fishers and consumers were collected using a pretested semi structured questionnaire. Time series data from 1976 to 2011 was generated from the Traditional Fishery Data Base at Fisheries Research Station. The logistic regression analysis showed that the goodness of fit Hosmer and Lemeshow test yielded c2 (8) of 6.924 and was insignificant at 0.05 (P = 0.214). The -2 Log Likelihood showed that the model fitted the data at an acceptable level (P = 0.001). Six predictor variables (stratum, marital status, literacy, years in fishing and daily working hours) were significant. Autoregressive Integrated Moving Average model (0, 1, 1) was selected. From the selected model, at the current exploitation rate it was forecasted that Chambo catches would decline to -1,111.80 tons in 2021 from 4,118 tons in 1976. From the Gordon Schaefer dynamic model, it is estimated that the economic rent at maximum economic yield, is MK2.148 million as compared to MK1.533 million at maximum sustainable yield. The Gordon Schaefer bioeconomic model showed that high economic rents are associated with maximum economic yield than maximum sustainable yield. Based on the bioeconomic analysis, it is recommended that Chambo fisheries be managed at maximum economic yield, which implies reducing the current fishing effort.

Key words: Logistic model, Lake Malombe, forecasting, bioeconomics, economic rent.

African Journal of Fisheries Science Vol. 2 (3), pp. 084-089, March, 2014. © International Scholars Journals

Full Length Research Paper

Discovery study of the outcome of inland fisheries decree on sustainable exploitation of inland fisheries in Lagos State, Nigeria

Ephiede J. Adebisi, Adetarami Dudusola and Akinlade S. Temenu

Department of Wildlife and Fisheries, Faculty of Agriculture, University of Ibadan, Nigeria. Email:[email protected]

Accepted 28 February, 2014

Abstract 

To achieve sustainable and socially beneficial exploitation of the fishery resources led to the promulgation of the Inland Fisheries Decree 108 of 1992. The objective of this study was focused on whether the inland fisheries decree has significantly curbed the various threats to inland fishery stocks and the development of artisanal fishery Four communities (Ibeshe, Iyagbe, Agbowa-Ikosi and Ebute-Afuye) in Lagos State were purposively selected. With the aid of simple random sampling, 309 fisher folks were interviewed. Thirty (30) fisher folks were arranged for FGDs in each of the communities and group discussants were stratified into adult men, women and youths. The key informants interviewed were traditional rulers and the head of fisher folks. Data was analysed using descriptive statistic and Pearson Chi-square. The results reveal that with the level of significant (0.05) the null hypothesis was rejected. The study concludes that the fisher folks’ perception of the fisheries decree is significantly related to conformity with the decree. The provisions of the decree did not exhaust the register of threats to artisanal fishery. The decree did not address the problem of pollution and open access regime in artisanal fishery. The decree is grossly violated by the artisanal fisher folks. They use small mesh nets and unorthodox (plant derived poison) fishing methods. The reasons for the violation of the decree were: penalties for violation are too cheap to have any impact; and poor monitoring and enforcement of the decree. The study recommends that government should invest the authority to manage and control the exploitation of fishery resources on the artisanal fisher folks. The decree should be reviewed and be well enforced. Such review should accommodate wider consultation of fishery experts, as well as participatory in-puts, mobilization and sensitization of artisanal fisher folks.

Key words: Explorative analysis, inland fisheries decree, artisanal fishery sector.

African Journal of Fisheries Science Vol. 2 (3), pp. 077-083, March, 2014. © International Scholars Journals

Full Length Research Paper

The condition of mangrove muddy crab fishes in Kenya, East Africa

Amobi Musyoka, Bochabery O. and Brayant Ajwang

Department of Fish economics and management, Faculty of Agriculture, University of Nairobi, Nairobi, Kenya. Email:[email protected]

Accepted 07 February, 2014

Abstract 

Mangrove mud crabs, Scylla sp. are among crustaceans of commercial value along the Kenyan coast and in many mangrove areas in the Western Indian Ocean region. In Kenya the crabs are landed by artisanal fishermen. Rising population in the coastal areas and high demand for the crabs has led to increased pressure on the crabs. The population structure and maturity stages of Scylla serrata from Ngomeni - Fundisa area of Malindi were investigated from July 2005 to July 2006. The size of crabs caught ranged from 50 to 125 mm carapace length, with crabs of 75 mm carapace length dominating. Male crabs dominated in the captured population. Linear relationships were obtained for both female and male crabs for the Carapace length - Carapace width. The size at first maturity was at 75 and 70 mm carapace length for male and female crabs respectively. There is an indication of exploitation pressure on the population and to ensure sustainable management, regulation on the minimum size of the crabs to be caught is recommended.

Key words: Malindi, mangroves, maturity stages, mud crab, population structure, Scylla serrata.

African Journal of Fisheries Science Vol. 2 (2), pp. 070-076, February, 2014. © International Scholars Journals

Full Length Research Paper

The outcome of various stocking density of bottom feeder fish Cirrhinus mrigala and Cyprinus carpio on growth performance and fish yield in polyculture system

Hasnain O. Altaf, Farhanullah k. and Fahim Jahanzeb

Department of Fishery, Faculty of Agricultural Sciences, Allama Iqbal Open University, Islamabad, Islamabad CT, Pakistan. E-mail: [email protected]

Accepted 28 January, 2014

Abstract 

The present project was planned to study gradual replacement of Cirrhinus mrigala with Cyprinus carpio and its impact on pond ecosystem. A total of 900 fishes belonging to six species viz. Catla catla, Labeo rohita, Cirrhinus mrigala, Ctenopharyngodon idella, Hypophythylmichthys molitrix and Cyprinus carpio were stocked in four earthen ponds. The dimensions of each pond were 220 × 198 × 7 feet length, breadth and depth. The stocking density in pond 1 (T1) was C. catla 150, L. rohita 200, C. mrigala 200, C. idella 150, H. molitrix 150 and C. carpio 50. The stocking density of C. mrigala and C. carpio in pond 2 (T2) was 150 and 100, in pond 3 (T3), 100 and 150 and in pond 4 (T4) it was 50 and 200, respectively while the stocking density of all the other four fish species remained constant in all the four ponds. All the fish were fed with a diet of 25.16% crude protein at 2% body weight. C. idella and C. mrigala showed maximum growth in T1, C. catla and H. molitrix in T2, L. rohita and C. carpio in T3. Maximum growth was observed in T3 followed by T4, T1 and T2. Among fish species C. idella and C. carpio showed higher growth rates than the rest of fish species. Our results reveal that in polyculture system stocking density of C. mrigala and C. carpio in a ratio of 1: 1.5 gives better results.

Key words: Aquaculture, freshwater, phytoplankton, zooplankton, exotic fish.

African Journal of Fisheries Science Vol. 2 (2), pp. 062-069, February, 2014. © International Scholars Journals

Full length Research Paper

Active Population of the edible clam Meretrix casta (Chemnitz) (International Union for Conservation of Nature status: weak) from two estuaries of North Kerala, south west coast of India

Ranjan Mansuri

Department of Fish Extension Education, College of Fishery Science, Assam Agricultural University, Jorhat, Assam, India. E-mail: [email protected]

Accepted 01 January 2014

Abstract

The population parameters of the edible clam Meretrix casta (Chemnitz) from two estuaries along the coast of north Kerala, Southern India were estimated. M. casta has been cited as vulnerable as per al. (2006a). Growth of M. casta from the east coast has been reported by Abraham (1963), Durve (1970: 73) and Sreenivasan (1983). Jayawickrema and Wijeyratne (2009) have described the population dynamics of M. (IUCN) population status. The asymptotic length (L∞) for M. casta from Chaliyar estuary was 24.24 mm. The growth coefficient (K) was 1.8^-1. The growth performance index (ф') was found to be 1.92 and _t0 was calculated at -0.04283547 years. The length weight relationship is given by Log Y = -1.259635861 + 3.090977418Log X, r = 0.903010085. The total mortality (Z) estimate for M. casta from Chaliyar estuary was 3.92 year^-1; fishing mortality (F) 2.12 year^-1. Exploitation level (E) was 0.54. The asymptotic length (L∞) for M. casta from Kavvai estuary was 26.5 mm. The growth coefficient (K) was 2.0^-1. The growth performance index (ф') was found to be 2.03 and _t0 was calculated at -0.03441665 years. The length weight relationship is given by Log Y = -0.98701877 + 3.054878207 Log X, r = 0.613724895. The total mortality (Z) estimate for M. casta from Kavvai estuary was 2.98 year^-1; fishing mortality (F) 0.98 year^-1. Exploitation level (E) was 0.33. The M. casta is under exploited from both the estuaries. There is potential for increased exploitation of the edible clam from both estuaries since the present exploitation levels are far below the maximum sustainable yield (MSY).

Key words: Meretrix casta, population dynamics, Chaliyar, Kavvai estuaries, south west coast of India.