Presentation on theme: "A. Y. KARIKARI & RUBY ASMAH. Institutions involved: CSIR Water Research Institute Institute of Aquaculture, University of Stirling, UK. Duration of Project:"— Presentation transcript:
Institutions involved: CSIR Water Research Institute Institute of Aquaculture, University of Stirling, UK. Duration of Project: 3 years (12/2012 to 12/2015) Funding: Royal Society Leverhulme African Award, UK
Water Research Institute ◦ Dr. Ruby Asmah ◦ Dr. Joseph Ofori ◦ Dr. Hederick Dankwa ◦ Mr. Anthony Karikari (PhD student) Institute of Aquaculture ◦ Prof Lindsay Ross ◦ Dr. Trevor Telfer
Fish production from cage fish farming currently accounts for more than 80% of aquaculture production in Ghana (Fisheries Commission 2012 – unpublished data) There are more than 58 individual fish farms sited on the Lake with over 1700 cages (Fisheries Commission 2010 – unpublished data) Production capacities vary from small scale to large commercial scales.
The cages are largely sited in Stratum II of Lake Volta
Cage culture has both positive and negative impacts.
It is a “cheap” source of protein Enhances food security, health and wellbeing of the people
A major source of income to riparian communities Poverty alleviation Community development (eg access road, provision of electric power, schools etc)
Women processing fish – charges a fee per weight of fish Fish fat extraction for processing and sale
Like many other farming activities, aquaculture relies on the use of natural resources such as land, water, seed and feed. Its growth always involves: ◦ The expansion of cultivated areas, ◦ Larger aquaculture farms, ◦ Higher stocking densities ◦ Increased use of feed resources Wastes are generated as a result
The fish farmers rely on the environment to dissipate and assimilate the waste generated The nature and extent of environmental consequences of cage aquaculture are often dictated by the attributes of: ◦ location (hydrology, current speed etc) ◦ intensity of production ◦ production practices ◦ species cultured and ◦ feed types used.
Real and/or perceived impacts of cage culture systems on the surrounding aquatic environment and ecosystem include the following (Tacon and Halwatt (2007)): o Nutrient enrichment in water column and bottom sediment - High phytoplankton bloom -High NH 3 -High NO 2 -Low DO, high turbidity ◦ Increased risk of disease occurrence on cage reared fish and the potential to transfer disease to natural fish populations
◦ Increased risk of fish escapes and consequent potential impacts on wild fish populations including potential genetic, ecological and social impacts ◦ Increased community concerns regarding the use of public shared inland waters for rearing fish ◦ Increased need for the establishment of adequate governmental controls.
To build capacity in environmental monitoring and assessment and to formulate a plan for improved and sustainable cage aquaculture on the Volta lake
To determine the impacts of cage culture on water quality, bottom sediments and benthic communities (ecology) of the Volta Lake To build skills in environmental monitoring and impact assessments To provide guidelines for sustained cage aquaculture in the lake Volta
3 Training workshops Year 1 – Environmental management for Sustainable Cage Aquaculture Year 2 -Advanced Environmental Modelling Year 3 –Presentation of project activities and findings Hydrographic data collection Field sampling of water and sediments
Laboratory Analyses of samples Modeling Training of MSc Students & 1 PhD student Journal Publications
Main Lake (Gorge Area) Farm Name: Lee Farm Location: Ajena Species Cultured: Tilapia Production Level: 64 Mt No. of cages: 168 Average size of cages: Broodstock (108) -4m x 4mx1.5m Fry (5) – 4m x 4m x 1.5m Fingerling (23) – 5m x 5m x 1.5m Grow out (32) – 4m x 4m x 4m
Main Lake Farm: West Africa Fish (WAF) Location: Asikuma Years of Operation: 5 Species Cultured: Tilapia Current Production: 2,300 Mt No. of cages: 80 Circular cages 16m radius x 6m Rectangular cages – 6mx6mx3m
Hydrographic data Current velocity and direction Based on depth of water, data will be collected from two to three depths Four field measurements in a year to cover both major and minor wet and dry seasons Data collection will be at 20 - 30 mins interval Equipment - Drogue Bathymetry? Wind speed
Water Quality Measurements Bimonthly sample collection from all the sites WQ parameters include: pH, DO, Temperature, Conductivity, Turbidity, Nutrients, Metals, COD, Transparency, Chlorophyll-a Sediment Quality Bimonthly sampling Parameters – C, N, P, benthic communities, pH, H 2 S, conductivity, redox potential, metals, particle size analysis. Some laboratory experiments
Estimation of quantities of waste discharged from fish cages to the Lake Mode of aquaculture waste dispersal and identification of potential impact areas Interactions between aquaculture and the environment and potential impacts on biota Improved capacity in environmental impact assessment studies in relation to aquaculture
New approaches and methods in environmental monitoring and assessment Better understanding of cage aquaculture and its potential impacts on the lake Optimization of site selection on the Lake
A paper titled “Assessing the impacts of cage fish farming on benthic communities in sediments of Lake Volta” has been accepted for oral presentation at the 15 th World Lakes Conference in Perugia Italy from 1 st to 5 th September 2014.
Continuation of Drogue measurements of water current speed and direction at different depth at WAF, Kpeve and Lee Continue bi-monthly sampling of water and sediment quality Two more MPhil students to handle aspects of the project (macroinvertebrates, drogue)
At least one conference paper presentation Completion of projects by current MPhil students Completion of two chapters by PhD student
Distillation plant Deioniser Van Dorn Water sampler Ekmans sediment grab Filtration kits Life jackets DO – temperature probe Sieves and shaker for particle size analysis Echotest depth sounder GPS devices etc.
CSIR Water Research Institute (CSIR-WRI) Environmental Protection agency (EPA) Volta River Authority (VRA) Water Resources Commission (WRC) Ministry of Food and Agriculture (MOFA) Fisheries Commission Ghana Water Company (GWCL)
Department of Fisheries and Watershed Mgt. KNUST Irrigation Development Authority (IDA) Aquaculture Farmers Fish Sellers NGO’s