Tanga Fisheries Analysis - IUCN

produced of mean catch per trip against mean price per kilo by year and month (again just for
Kigombe Village data). The data are presented in Figure 26. The prices were adjusted by fixing the
annual price (value) of a US Dollar (in Tanzanian Shillings) to the 1996 mean annual US$
exchange rate against the Tanzanian Shilling using data obtained from the Tanzania Bureau of
Statistics.
It is difficult from this data to immediately determine the nature of the relationship between price
and the supply of fish, and an analysis of price elasticity of supply would be a useful. Price elasticity
of supply (PEoS) describes how sensitive supply is to the price of a good or service. Producers
(fishers in this case) will theoretically supply less of a product if the price is high (because they can
earn a certain level of revenue supplying fewer units of goods or services than when the price per
unit is low). If fishers are sensitive to this opportunity they would be able to spend less time fishing
for the same income, and perhaps engage in other economic/subsistence activities. If supply is not
sensitive then they will still supply as much fish as they can whatever the price at market.
Selections of a run of price increase were made from the data for each of 6 CMAs and the mean
catch per trip was used as a proxy for the supply (assuming that the mean catch from the sample
reflected the mean catch across the entire fishery in each CMA and therefore the total level of
supply). In all CMAs, except Boza-Sange, the price elasticity of supply was less than 1, which by
rule of thumb indicates that supply is not sensitive to price. Boza-Sange had a PEoS of 1.4, which
suggests some sensitivity to price.
There are two important caveats in interpreting such an analysis. Firstly, the quality of the estimate
of the total fish supply is very important but because the VAS and BAC data are not adequately
collected the detailed monthly estimate of catch (supply) may be relatively low in accuracy.
Secondly, if prices are fixed by buyers in exchange for a loan before fishers go out fishing they are
become somewhat independent on the actual supply. A useful activity for TCZCDP would be to
undertake a survey of market auctioneers and/or senior fishers to evaluate their perceptions of
price changes and influences on price. If data on the costs of fishing gear was obtained over the
period in question then it would be possible to develop a Terms of Trade Indicator analysis (James
Wilson, SADC/MCS Economist, pers. comm.)
Another way of looking at the relationship between supply and price of fish can be illustrated
graphically by scatter-plots of mean catch (again as a proxy for supply) against the mean price per
kilogramme) from 2003/04 data. The only CMA that appears to have a significant relationship
between price and supply is Mwarongo-Sahare, which includes Tanga Town, a major market, and
possibly Mtang’ata. Note that mean price per kilogramme of fish appears to reduce as one moves
south from Boma-Mahandakini in the north of Tanga Region to Mkwaja-Sange in the south. This
may reflect the poorer infrastructure and distance to the main market of Tanga.
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