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IR 2: Science and Technology Applied to Policy and Management
This component area seeks to improve fisheries management processes by engaging scientific research and findings as part of the driving forces and rationale for management.
2.1 Scientific and Technical Working Group
A Scientific and Technical Working Group was formed in Year 1 to provide information on status of stocks to inform decision-making. The group met four times during the year and the
outcome of the first meeting included the election of the STWG Chairman Professor Kobena Yankson from UCC and Vice Chairman Mrs. Patricia Markwei from FC-retired. In addition, a
six member sub-committee for stock assessment was nominated including representatives of the artisanal fishers, inshore fishers association and women fish processors.
A summary was prepared on historical landings by month by gear from 1980 to 2014, fisheries independent biomass estimates by acoustic surveys, examination of environmental factors and
preparing an overfishing definition for the stocks. The sub-committee reviewed potential management options developed by SFMP which were then disseminated to stakeholders during
consultation meetings.
The initial stock assessment was completed and reviewed by the STWG. The model used landings and effort data collected by the Fisheries Commission FSSD. The effort data consisted
of fishing trips by month of the artisanal small pelagics fishery. This consists of purse seines and encircling gillnets, known as Ali-Poli-Watcha APW. The effort data presented a bias due to the
significant changes occurring over time in the size and efficiency of fishing gear, canoes and technologies. The data will be standardized using the results from the historical perspective
survey conducted by Hen Mpoano. An alternative measure of nominal effort was then used as the count of fishing canoes using purse seines. The main small pelagic fish species are the round
sardinella
Sardinella Aurita
, the Madeiran sardinella
Sardinella maderensis
, anchovy
Engraulis Encrasicolus
and mackerel
Scomber japonicas
.
Figure 9 Landings of most important small pelagics fish in Ghana source FCFSSD
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Rebuilding target
Overfished Not Overfished
The stock dynamics of small pelagic were simulated using a biomass-dynamic model with observation error estimation. The exploited population was assumed to grow according to the
logistic Schaefer model. Useful management quantities for sustainable fisheries can be derived from the logistic model parameters as follows:
Results are preliminary subject to approval through the independent peer review panel anticipated to take place in Accra during the second quarter of Year 2. Results show that the
small pelagic stock is severely overfished. Landings have declined precipitously and currently Fmsy = r 2 q = 0.40
Bmsy = K2 = 310,476 MT
Figure 10 Effort in number of canoes recorded by frame surveys source FCFSSD
Figure 11 Biomass rebuilding target
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account for only 15 of the highest value recorded in 1997. The STWG recommends a swift management action which can reduce fishing pressure on the stock through various management
measures i.e. closed season coupled with a reduction in fishing effort, closed areas and control of illegal fishing. If management lags behind these trends, the population will be driven to
collapse. Other considerations will be examined in Year 2 as such species are sensitive to environmental variability and need to be taken into account for a rebuilding strategy. The
recommended reference target is to reduce fishing mortality from 0.7 to 0.4.
2.2 ICT Innovations for Effective Fisheries Management
