Fixed costs, i.e. those costs that do not change with the level of fishing effort, arc the canoe, fishing gear, licensing fees, interest due on borrowed capital and depreciation of the different assets. The biggest component of the annual fixed costs for net fishing is the depreciation of the net. The costs of mounting the net were included in the total price of nets (an average of ZK 856 for rope and ZK 82 for twine). The lifetime of nets is variable and was difficult to estimate. It depended on whether they were used as seine or gill nets and also whether there were many stumps in the reservoir. From the survey and informal discussions with officers from the Department of Fisheries, it was expected that nets could last about 2 to 3 years. No interest was charged on the loans made.
The average life expectancy of dug-out canoes was also estimated at 2 to 3 years. It depended on the material used to build them and how long they were in the water. Because all net fishers in Kangombe used canoes, their fixed costs were higher than those for Makungwa dam.
There were no fixed costs for the other types of gear.
Variable costs, i.e. those costs which vary with the level of fishing effort, can include bait, repairs of gear and canoe, crew's wages and/or shares, and transport.
The two components of variable costs for net fishing were repairs of nets and crew's shares. Nets were usually repaired by the fishers themselves with local materials. Therefore, the financial costs involved were minimal.
Two types of crew were employed, depending on the fishing method used and whether the owner lived in a nearby village or was an outsider. If he was a local fisher and thus only fished part-time, he would also ‘employ’ his helpers on a part-time basis. These helpers could be relatives, friends or farm workers who assisted him during the fishing. In the latter case, the fishers camped at the dam site and fished full-time. These fishers usually came with regular workers who assisted them continuously. For gill netting one or two persons can set and haul the net. However, for seining more people were needed to pull the net. If the net is not hauled fast enough many fish escape. Therefore, often helpers from nearby villages were asked to assist with seining. These were just hired for the day. Exact details of crew remuneration were not obtained during the survey. During informal discussions with other fishers, it was learnt that the remuneration of the local helpers depended entirely upon the owner of the gear. No agreements were made before fishing started. If these helpers thought they did not receive a fair share of the catch they could complain to the village headman. The headman could try to negotiate with the net owner but could not dictate the amount to be paid to the crew. The regular workers were either paid in fish, which they could then dispose of if they wanted, or were given a fixed salary.
The variable costs for hook and line fishery were made up of hooks and line only. The bait was never bought. The variable costs for the other types of fishery were nil.
It is clear that the operational costs for all types of fishery were kept to a minimum. The main inputs were labour and time. The majority of the fishers fish part-time, i.e., only when their other activities did not demand their input. Therefore, the opportunity costs for labour approached zero.
The relatively high initial capital investment of buying a new net, restricted the entry into net fishery.
Catches were kept for home consumption, sold, given away to relatives and friends or were bartered for other essential commodities. The distribution of the catch over these four categories differed per dam and per fishery (see Figure 7).
In general, the biggest part of the catch was consumed by the fisher's own household with the exception of net fishers in Makungwa dam. These full-time fishers had to make their living from fishing and they also had higher catches. The net fishers in Kangombe, on the other hand, consumed 46% of the catch and only sold fish if the catches were good.
Table 9: Reasons to fish (% of respondents)
| Item | Net | Trap | Hook & Line | Other Gear |
| For consumption | 11 | 58 | 74 | 70 |
| For sale | 11 | 1 | 1 | 0 |
| Both | 78 | 41 | 25 | 30 |
The reasons for fishing are summarized in Table 9. These results partly correspond to the way the fishers actually disposed of the catches. Apparently, many fishers would like to sell their surplus, but only 19% of the trap fishers, 16% of anglers and 3% of those using other gear did so. It is thus not surprising that nearly all fishers said they wanted to catch more fish (see Table 10).
Table 10: Fishers aspiration to have more fish (% of respondents)
| Item | Net | Trap | Hook & Line | Other Gear |
| No | 0 | 2 | 2 | 0 |
| Yes, for consumption | 61 | 89 | 83 | 88 |
| Yes, for sale | 94 | 62 | 50 | 49 |
The data also highlight the fact that the actual catches did not even satisfy the demand for fish for home consumption.
At Makungwa most of the fish was marketed at the dam because it was close to the main road (Chipata-Lusaka). This specific location has increased the prices and consequently, limited the access to fish for the non-fishing community members. In Makungwa, only 29% of the non-fishers occasionally bought fish. In Kangombe and Chadewa, the figures were. 79% and 51%, respectively. In Kangombe and Chadewa, fishers also tended to share fish more often than in Makungwa. Twenty seven percent of the non-fishers in Kangombe and 32% in Chadewa did receive fish every now and then, while this was only 5% in Makungwa.
The catches were often sold at different places. Some customers came to the dam to buy the fish. The remainder was taken for sale in the villages or at the roadside. It was rare that fishers sold fish from their homes. The ‘sales system’ differed for each dam, depending on its location with regard to the villages, main roads and towns. Figure 8 depicts the places where the majority of the non-fishers in the communities surrounding the dams bought their fish from.
Fish were sold in cups or small plates (Barbus spp.), in heaps (bream) or per piece (bigger size catfish and Labeo). The prices differed per species. Catfish was the most expensive, followed by bream and Labeo. Barbus was relatively expensive. In general, a cup of small fish equalled the price of 3 to 4 medium size breams. The prices also varied per dam. As said before, the highest prices were obtained at Makungwa Dam. For example, the average price of a catfish here was up to 60% higher than in the other dams, and on average bream cost more than twice as much. There were probably seasonal variations in prices as well, but these could not be detected with this short survey.
The revenues for a fisher consequently depended on the catch composition and the size of fish caught by the gear used. The catches for net fishers in Kangombe dam were considerably lower than those in Makungwa dam. The fishing pressure in Kangombe was more or less constant throughout the year (it varied with the labour demands for the agricultural activities). The local fishers fished in the dam year after year, while in the Makungwa reservoir no net fishing had taken place for several years. The full-time fishers only stayed there for several months. When the catches went down they moved to another reservoir.
Figure 8. Sales point for fish
During the study, the portion of fish allotted to home consumption, barter or to give away to friends or relatives was registered separately. It was assigned a market value to compare the revenues of the different types of fishing units. Table 11 summarizes certain features of the different fishing units.
Tables 12, 13, and 14 indicate the annual incomes for each gear type operating in the three reservoirs. It is clear from these estimates that the net fishery was the most profitable fishery on Makungwa dam. On the other reservoirs, the trap fishery gave the highest profits (Appendix 2 gives details on how costs and income was calculated).
A sensitivity analysis on incomes of net fishers, trap fishers, anglers and those using other gear is given in Appendix 3.
For Kangombe and Lutembwe dams where catches were reported to be relatively low for net fishers, the incomes were most sensitive to changes in catches (a 10% increase in catch would increase their profit with 61.5% and 56.5% respectively) compared to 21% for Makungwa (at a constant cost price).
The effect of an increase in the selling price of fish depends on the percentage of catch being sold, In general incomes of net fishers were more sensitive to a price increase than the other type of fishery because they sold the highest proportion of their catches. Of course higher prices may bring about a shift in the way the catches are used.
All net fishers will loose part of their income when costs increase. An increase in the fixed costs (price of nets, canoes, and licensing tees), has the biggest effect on fishers in Kangombe (-30.5%) and Lutembwe (-21.5%). With a 10% increase of the variable costs, the fishers in Makungwa would loose 11%, in Kangombe 21% and in Lutembwe 25%. The incomes of the net fishers in Makungwa are more sensitive to an increase in variable costs than fixed costs because they spend a relative large amount on payment of regular workers and casual helpers.
Since there were no financial costs for trap fishers and those using other gear (spears and grass bundles), an increase in costs does not affect them. The costs of lines and hooks for anglers was so low that their annual income would not change if costs increase by 10%. However, the initial investment may discourage lower income people (to which women often belong) to angle.
Table 11: Features of different fishing units (as determined by the socio-economic study)
| ITEM | NETS | TRAPS | H & L | OTHER GEAR | |
| GRASS BUNDLE | SPEARS | ||||
| Reason for fishing | |||||
| Consumption | * | * | * | * | * |
| Sale | * | ||||
| Efficiency | |||||
| High | * | * | |||
| Moderate | * | * | * | * | |
| Low | * | ||||
| Required Investment | |||||
| High | * | ||||
| Moderate | * | ||||
| Low | * | * | * | ||
| Running cost & Recurrent expenditures | |||||
| High | * | ||||
| Moderate | * | ||||
| Low | * | * | * | ||
| Profit margins | |||||
| High | * | * | * | ||
| Moderate | * | * | * | * | |
| Low | |||||
| Disposal of fish | |||||
| Consumption | 41% | 64% | 72% | 84% | 93% |
| Distribution | 11% | 9% | 9% | 9% | 7% |
| Barter | 5% | 2% | 2% | 0% | 0% |
| Sale | 41% | 24% | 17% | 6% | 0% |
Table 12: Annual incomes by type of gear (ZK) for Makungwa dam
| Item | Nets | Traps | Hook & Line | Other Gear |
| Fixed Costs | 1 172 | 0 | 0 | 0 |
| Variable Costs | 18 844 | 0 | 17 | 0 |
| Total Costs | 20 016 | 0 | 17 | 0 |
| Total Revenues | 37 605 | 14 925 | 6 986 | 11864 |
| Profit | 17 589 | 14 925 | 6 969 | 11864 |
Table 13: Annual incomes by type of gear (ZK) for Kangombe dam
| Item | Nets | Traps | Hook & Line | Other Gear |
| Fixed Costs | 1 306 | 0 | 0 | 0 |
| Variable Costs | 916 | 0 | 16 | 0 |
| Total Costs | 2 222 | 0 | 16 | 0 |
| Total Revenues | 2 652 | 12 925 | 2 581 | 12 314 |
| Profit | 430 | 12 925 | 2 565 | 12 314 |
Table 14: Annual incomes by type of gear (ZK) for Chadewa dam
| Item | Nets | Traps | Hook & Line | Other Gear |
| Fixed Costs | N/A | 0 | 0 | 0 |
| Variable Costs | N/A | 0 | 16 | 0 |
| Total Costs | N/A | 0 | 16 | 0 |
| Total Revenues | N/A | 12 219 | 7 248 | 5 976 |
| Profit | 12 219 | 7 232 | 5 976 |
Figures are based on the results of the questionnaires. Prices for May 1990 were used.
The sensitivity analysis shows the greater vulnerability of the incomes of the local net fishers in Kangombe and Lutembwe compared to those in Makungwa. It also shows that the trap fishery, rod fishing and fishery with other gear are able to absorb adverse changes in the fishery more successfully than the net fishery. However, this sensitivity analysis does not show how the first three categories of fishers value their time. It is possible that although the fishery is still profitable, some fishers may stop or reduce their fishing efforts because they prefer to do something else with their time.
6 May 1990 Exchange Rate USS1 = ZK40
