Interdisciplinary
Project 2013
Students:
Daphne van den Berg 10024298
Ecology Demian Siffels 10069070 Economics
Simone van der Meer 10069755
Political Science
Tutor: Yrrah Stol -- ABSTRACT –-
The fishery-based economy surrounding Lake Victoria is dependent on the existence of the exotic species Nile perch. However, the introduction of this species, in the 1950s, caused a disturbance to the lake’s biodiversity. As a consequence, several species were depleted. Nowadays, the population of the Nile Perch itself is declining mainly due to overexploitation and eutrophication of the lake. This paper will try to answer how policy could help to maintain the fishery-based economy around Lake
Victoria. It is suggested that the present algae blooms in Lake Victoria should be combatted to reduce eutrophication. To address overexploitation, quotas (MSY) might be useful. It is suggested that the economic consequences of the quota will be
limited, due to the strong bargaining position of Lake Victoria. However, it is not likely that one of the current stakeholders is able to implement such measures,
because they lack power, or because they tend to free-ride. Therefore, it is recommended that an umbrella organization could be established in order to enforce
Lake Victoria & the Nile Perch Economy
Providing a sustainable fishery-based livelihood
Table of Content
Introduction... 3 Theoretical framework... 6 Ecology... 6 Political Science... 7 Economy... 8 Methods... 10 Results... 11Food web changes... 11
Biodiversity loss... 12
Eutrophication... 12
Current situation of the Nile Perch... 13
Biodiversity... 13
Eutrophication... 14
Market Position... 16
Fishery-Based Community... 18
BMUs... 19
Kenya, Tanzania & Uganda... 19
Lake Victoria Fisheries Organization (LVFO)...20
Importing Countries & Sponsors... 20
Collective Action Problem... 21
Poverty & Food Insecurity... 21
Financial Needs... 22
Umbrella Organization... 22
Conclusion... 27
Discussion... 28
Literature... 29
Appendix A: Objectives Parties Involved... 34
Introduction
The introduction of an exotic species can have unexpected devastating effects on the ecosystem. In Lake Victoria, the introduction of the Nile perch in the mid-1950s initiated the collapse of the Lake Victoria ecosystem (Pringle, 2005). The Nile perch population had no natural competitors and increased explosively in the 1980s. Consequently, the ecosystem changed drastically. In total, 300-500 (approximately 65%) endemic species nearly vanished from the lake due to predation by the Nile perch (Downing et al., 2013; Witte et al., 2012; Awiti, 2011).
The explosive growth of the Nile perch did have economic benefits on the short term. It increased the economic importance (measured in GDP) of fishery in the Lake Victoria area fivefold (Reynolds et al, 1995; cited in Pringle, 2005). The Nile perch is mostly used for export. The economy in the Lake Victoria area is now largely dependent of their fish export for which the Nile perch accounts for over ninety percent (Njiru et al., 2008). To maintain the fishery based economy, it is crucial to have a sustainable fish stock, since it will provide the local fishermen with a stable income.
Nowadays, however, the Nile perch is overfished and eutrophication is threatening their existence as well. Their exact level is unknown, but between 2005 and 2008 there was a drop of 81% (Reuters.com, 2009). This drop initiated a partial resurgence of haplochromine cichlids from refugia lakes (Kishe-Machumu et al., 2012). However, increased haplochromine cichlids populations cause the Nile perch to mainly feed on them again. The declining fish stocks pose a threat to a sustainable1 income for the local fishermen. Therefore, it is crucial to examine what
policies are able to secure a stable fish stock. However, the introduction of policy measures may be problematic since the lake is divided amongst three countries; Kenya owns 6%, Ugunda 45% and Tanzania 49% (Bokea & Ikiara, 2000). Even though Kenya only owns 6% of the lake, this part is most intensively fished. Therefore, policy measures need to include all countries. However, because the lake contains common resources without clear-defined property rights, it is hard to make any agreements between involved parties.
Economic Relevance
To get more insight in the economic importance of the Nile perch for the different countries, the economic relevance will be discussed.
1 In this report, ‘sustainability’ will be defined as by Brundtland (1987): ‘development that meets the needs of the present without compromising the ability of future generations to meet their own needs’
By 2005, fishery made up about 0.5% of Kenya’s Gross Domestic Product (GDP), with 55,000 people working in fisheries. This translates into almost 50 million US$ worth of exports. About 92% of the catch comes from Lake Victoria of which the Nile perch makes up the gross part (FAO, 2007).
For Uganda, fishery made up about 0.5% of its GDP, by 2005, with 150,000 people working in fishery. Uganda exports about 40.6 million US$ worth of fish. Lake Victoria also makes up the gross part of Uganda’s fishery of which the Nile Perch accounts for almost half the yield (FAO, 2007).
By 2005, fishery made up about 2.5% of Tanzania’s GDP, with 150,000 people working in fishery. This translates in about 145 million US$ worth of export. About 37% of this comes from only the Nile Perch in Lake Victoria (estimate based on FAO data of total fish yield and Nile Perch yield) (FAO, 2007).
Thus, even though the fisheries only account for a small percentage of GDP, in all countries Lake Victoria is the most important source. Finally, the industry makes up a combined 235.6 million US$ of exports employing around 355,000 fishermen.
Interdisciplinary Approach
It is evident that the Lake Victoria subject is complex at economic, ecological and political level. Therefore, not one single discipline’s insights are sufficient to address this problem comprehensively. Economy and ecology in this problem are interconnected, because livelihoods of many local fishermen can only be maintained with stable fish populations. Economy overlaps with political science because problems like overfishing are sometimes addressed by using economic instruments such as taxes or licenses. Besides, the strong economic consequences of possible solutions might influence political desirability. Furthermore, governments pursue a stable and growing economy. This lead to the following research question:
To answer this question, the following sub-questions will be examined:
• Which ecological problems are currently present in Lake Victoria as a consequence of the invasion of the Nile Perch?
• In which way could eutrophication and overexploitation of Lake Victoria be combatted? • What are the macro-economic consequences of the different scenarios?
• What are the interests and stakes of the most important stakeholders in the Lake Victoria region? And what is their opinion about solving eutrophication and overexploitation? • What is the socio-political feasibility of implementing quota’s and cleaning techniques?
The report will start off with a theoretical framework. The theoretical framework contains underlying disciplinary theories which will be used to answer the research questions. Subsequently, the results regarding the research sub-questions will be outlined. Thereafter, a conclusion and discussion will follow.
Theoretical framework
Ecology
The introduction of the Nile perch initiated the collapse of the Lake Victoria ecosystem through an invasional meltdown. The invasional meltdown theory states that an introduced species has an accelerated damaging impact on the native ecosystem due to interactions with the native species. However, the presence of the introduced species could be additive as well which means that its presence does not alter the food web drastically (Sakai et al, 2001; Simberloff en Von Holle, 1999).
In Lake Victoria, the Nile perch does have a damaging impact on the native ecosystem. The Nile perch depleted its most profitable prey; the haplochromine cichlids. This can be explained by the optimal foraging theory. This theory states that the aim of predators is to maximize their net rate of energy intake. A predator will follow three rules. Firstly, a predator will always take the most profitable prey. Secondly, a predator will take or ignore less profitable prey. And thirdly, the inclusion of less profitable prey depends on the encounter rate of profitable prey (since a predator will prefer profitable prey above less profitable prey) (Barnard, 2004). This means that the Nile perch will always take haplochromine cichlids, unless their densities have gone too low. In those cases, they will forage on other species.
The alterations of the food web which the Nile perch caused reduced the resilience of Lake Victoria’s ecosystem. The resilience theory refers to an ecosystem its stability and capability of tolerating disturbance and restoring itself after a disturbance. Native species can cope until a certain threshold density (F2) has been reached by the introduced species, see figure 1. After this point, the ecosystem cannot maintain the introduced species anymore and it will grow exponentially. Subsequently, the ecosystem goes through a regime shift. A regime shift means that an ecosystem is rapidly reorganized from one relative stable state to another (Holling, 1973). To go back to the previous state with a regime shift, conditions have to increase to another threshold (F1).
In conclusion increasing biodiversity and reducing algae blooms are both useful ways to increase the resilience of Lake Victoria’s ecosystem.
Two ways to shift between alternative stable states. If the system is on the upper branch, but close to the bifurcation point F2, a slight incremental change in conditions may bring it beyond the bifurcation and induce a catastrophic shift to the lower alternative stable state (`forward shift'). A backward shift occurs only if conditions are reversed far enough to reach the other bifurcation point, F1 (Scheffer et al., 2001).
Political Science
The main political difficulty is that Lake Victoria lies in three countries and has numerous stakeholders. To identify these different stakeholders and their influences on each other, the theory of multi-level politics, as presented by Burgoon (2012), is used. This theory holds that different levels of politics interplay with each other. Due to globalization, national politics is increasingly influenced by other policy-making levels, namely, the international, regional, supranational/non-national, and subnational level.
Different theories will be used to explain why it is hard to make effective policy in the Lake Victoria case. One of the main problems of regional policy making is the collective action problem. Collective action problems are ‘obstacles to cooperation that occur when actors have incentives to collaborate but each acts in anticipation that others will pay the costs of cooperation’ (Frieden, et al., 2010, p. 56). States are likely to free ride; they would benefit from contributions to others while failing to contribute (ibid.), because this will increase their net benefits.
To explain why the local inhabitants do not have sufficient access to the lake’s resources, the theory of unequal ecological exchange (Rice, 2007) could be used. This theory suggests that the ‘structure of international trade shapes disproportionate access to global environmental space in a manner substantially predicated upon hierarchical position in the world system’ (p. 1369).
Economy
To assess economic consequences of policy measures, a thorough analysis of the market position of the Nile Perch is needed. The next concepts and theories are all applicable to the Nile perch situation. The first concept is that of a monopoly/oligopoly. A monopoly is whenever there is only one supplier in a particular market. The monopolist can use its market power to gain maximum profits. An oligopoly is when there are just a few sellers, therefore making some profits (Cabral, 2000). If there is not (nearly) equal competition such as in an oligopoly, but there is one supplier that is so large that other suppliers can be neglected, the supplier is said to be dominant. The other firms are called the competitive fringe and should provide some pressure on the dominant firm (Cabral, 2000). It is hard to identify which market is the most relevant to consider since one should know exactly how well fish types can substitute one another. Therefore, multiple markets will be considered. The Nile perch in Lake Victoria can be considered as dominant in the Nile perch market and can be considered as oligopolistic in the white fish market, as will be explained later on.
If the market for white fish is considered, the Nile perch also has a comparative advantage. As it is most commonly used, this theory states that in order for trade to occur, one should not look at the absolute efficiency (absolute advantage) of creating a product, but at the opportunity costs. Opportunity costs are other potential benefits that are foregone by creating the product and usually measured in terms of labor. This means, whenever a product is low on value it can still have a comparative advantage when the opportunity costs are lower than in another country (Landsburg, 2013).
If overfishing is tried to be solved with economic instruments, several theories predict that social problems will arise. First, there is the rational choice theory. This implies that every individual is solely driven by rational actions2. That means there is no emotion involved (Scott,
2000) and thus leads to the presumption that more is always better, at least for so called “normal goods” (Nicholson & Snyder, 2011). Secondly, there is the problem of externalities. Externalities arise whenever an action of one actor does not only influence its own well-being, but also that of others through other means than the price-system. There are positive externalities (doing something for yourself and unintentionally helping others) and negative externalities (doing something for yourself which causes negative effect for others) (Hindriks & Myles, 2006). If externalities are not taken into account, this can result in a tragedy of the commons, devised by Hardin (1968). This states that a shared common resource might deplete, 2 This basic economic assumption is not widely agreed. Some political scientist, for instance, argue that rationality is not always is not the only way in which actors make decisions; social, ethical, moral and emotional aspects also play a role. In order to bridge this communication gap, the term ‘rationality’ could be transformed to a continuous scale, ranging from perfectly rational (acting out of self-interest) to perfectly irrational (acting out of ethical, social, moral or emotional concerns).
because economic agents will maximize their own profit without considering the negative externalities imposed on others. Therefore, the social costs (with externalities accounted for) exceed private costs (without externalities accounted for) and the good is overexploited (Hindriks & Myles, 2006). Attempting to solve this problem, however, usually results in a free-riding problem; whenever there are shared benefits to be gained from investment, economic agents will rely on others to obtain this shared benefits (Hindriks & Myles, 2006).
Methods
Overall, the analysis is conducted with a literature study.
For the political science part, Google Scholar is used for the academic articles and different books are used to define basic political science concepts. Keywords as ‘political situation Lake Victoria’, ‘governance of trans-boundary waters’ and ‘social disruptions Lake Victoria’ were used. To identify the ideas from different stakeholders about how to handle the problems in Lake Victoria, the websites of the different actors3 (and the policy documents it
contained) were consulted. With searching machines, available on the websites, keywords as ‘eutrophication’, ‘quota’, ‘licenses’, ‘cleaning techniques’ were used, to get relevant information. However, it was difficult to find (relevant) policy documents. Therefore, a questionnaire was mailed to the different stakeholders4. The only stakeholder which replied was O.C. Mkumbo from
the Lake Victoria Fisheries Organization.
For the economic and ecological part, Google Scholar was also used for finding relevant academic articles. For the ecological analysis, keywords as ‘Nile perch level Lake Victoria’, ‘resurgence haplochromine cichlids Lake Victoria’, ‘eutrophication Lake Victoria’ were used. For the economic analysis, keywords as ‘Economic relevance Nile Perch’, ‘economic dependence Nile Perch’, ‘Economy Lake Victoria’. Also for export numbers databases of the FAO were consulted online (FAO,2007).
3 Lake Victoria Fisheries Organization (LVFO), Ministry of Fisheries Development Kenya, the Ministry of Livestock Development and Fisheries (Tanzania), the Ministry of Agriculture Animal Industry & Fisheries (Uganda), Global Environmental Facility, European Union (this website did not contain relevant information, therefore it is not used in the report)
4 Lake Victoria Fisheries Organization (LVFO), Ministry of Fisheries Development Kenya, the Ministry of Livestock Development and Fisheries (Tanzania), the Ministry of Agriculture Animal Industry & Fisheries (Uganda)
Results
The Nile perch became invasive 30 years after its introduction as a density threshold was reached, and disrupted its environment by rapidly depleting haplochromine cichlids in only 5 years (Ogutu-Ohwayo, 2001). Since the haplochromine cichlids are the Nile perch’s most profitable prey they focused especially on consuming haplochromine cichlids, thus the Nile perch is optimizing its net rate of energy intake (Barnard, 2004). Haplochromine cichlids are small fishes which are endemic to eastern and southern Africa. In Lake Victoria, they used to regulate the native shrimp, Caridina nilotica population by predation. Moreover, they graze algae which keeps the water transparent. Thus, the disappearance of the haplochromine cichlids caused a less stable food web and increased eutrophication which both resulted in loss of resilience (Goldscmidt et al., 1993).
The following paragraphs will provide more detailed information about the ecological problems which occurred after the invasion of the Nile perch.
Food web changes
By 1985, the haplochromine cichlids were virtually absent from the lake (Ogutu-Ohwayo, 2001). However, the Nile perch was able to switch its diet after the depletion of the haplochromine cichlids. Thus the absence of the haplochromines did not pose a serious problem to their survival. Instead they fed on Caridina nilotica, the carp Rastrineobola argentea and shifted to a predominantly cannibalistic life stage only when the Nile perch got too large to consume shrimp efficiently (Downing et al., 2013). The inclusion of less profitable prey depends on the encounter rate with the haplochromine cichlids, the most profitable prey, as the optimal foraging theory states. The population of Caridina nilotica increased greatly after the almost total disappearance of the haplochromine cichlids. Thus, the haplochromines were replaced by Caridina nilotica which ensured that sufficient food for the Nile perch was still available. In total 13 different haplochromine cichlid species were replaced by Caridina nilotica. Moreover, the Nile perch replaced more than 109 different haplochromine cichlids species. Aside from these replacements, Rastrineobola argentea replaced over 20 haplochromine cichlid species. Thus many haplochromine species disappeared from the lake and food web dynamic changed drastically (Goldscmidt et al., 1993).
Which ecological problems are currently present in Lake Victoria as a consequence of the invasion of the Nile perch?
Biodiversity loss
Biodiversity is important because it enhances the efficiency by which ecological communities capture resources, produce biomass and recycle essential nutrients. This means that in a biodiversity rich lake species levels grow faster than in a biodiversity poor lake (Caridinale et al., 2012, cited in Loreau & de Mazancourt, 2013). Thus, biodiversity increases the stability, or resilience, of ecosystem processes through time. Furthermore variations in resources will have a smaller impact on biodiversity rich lakes than on biodiversity poor lakes as biodiversity rich lakes will use the remaining resources more efficiently. Thus, biodiversity buffers against environmental variations.
If biodiversity is lost, ecosystem services will be more variable and less predictable. Therefore, biodiversity is critical to the long-term resilience (Loreau & de Mazancourt, 2013). As in Lake Victoria major biodiversity losses have occurred, its ecosystem services have become variable and unpredictable. Therefore, the threat of ecosystem service failure has increased.
Eutrophication
A current, serious problem relating to biodiversity loss is eutrophication. Eutrophication is another word for nutrient enrichment. Eutrophication was already present in Lake Victoria in the 1960s due to water pollution caused by an insufficient wastewater treatment. Therefore, heavy pollutants and fertilizers flow into the Lake (Downing et al., 2013; Wang et al., 2012). This influx of nutrients caused the present algae blooms in Lake Victoria (Ochumba & Kibaara, 1989). Algae blooms increase eutrophication. Firstly, algae blooms absorb sunlight which prevents other plants to receive sunlight. Secondly, less photosynthesis takes place in the water which causes oxygen levels to drop. Thirdly, less decomposition takes place because oxygen is required. And finally, nutrient levels increase as no decomposition takes place. Thus, eutrophication increases.
The disappearance of haplochromine cichlids has likely accelerated eutrophication, because they used to graze algae. Furthermore, the decreased photosynthesis in Lake Victoria resulted in deep water oxygen deficiency. This in turn caused even more cichlid mortality (Goldschmidt et al., 1993). Haplochromine cichlids may have faced the choice of death by suffocation in the deep anoxic water or predation by the Nile perch in the oxygen-rich shallow waters (Kaufman 1992, cited in Awiti, 2001). Thus, due to biodiversity loss the ecosystem has become less resilient because of increased eutrophication.
Current situation of the Nile Perch
Nowadays, the awareness arises that the Nile perch is being threatened as well. Their exact level is unknown, but between 2005 and 2008 a drop of 81% was present (Reuters.com, 2009). Since the local fishermen are economically dependent on the Nile perch it is necessary to maintain the Nile perch population in Victoria Lake. The most obvious threat to the Nile perch is overfishing. In sites where intense fishing occurs, a resurgence5 of some haplochromine species is present
(Kishe-Machumu et al., 2012). However, biodiversity is still much lower than before the invasion of the Nile perch (Witte et al., 2012). Therefore, haplochromine cichlids alone are not sufficient to provide local fishermen a sustainable income. Moreover, the Nile perch is being threatened as well by the eutrophication since less oxygen is present in the water.
In short, the ecological problems which are encountered in Lake Victoria are reduced resilience because of biodiversity loss and increased eutrophication. To increase the stability of Lake Victoria, biodiversity has to increase and eutrophication has to decrease. However, no linear relation is present between resilience and the ecological components biodiversity and eutrophication. There are several options to increase biodiversity and decrease eutrophication in Lake Victoria, which will be outlined in this paragraph.
Biodiversity
To increase biodiversity one could decide to introduce another species. However, this could lead to another invasional meltdown which is not desirable. Another option is to introduce cultured haplochromine cichlid species. However, they could disappear rapidly after their introduction because they would probably be predated heavily by the Nile perch again as the haplochromine cichlids are their most profitable prey. However, the haplochromine cichlids might survive because the Nile perch is threatened by eutrophication and overfishing. Another argument against the introduction is that it is an expensive solution. Thus, this is not a proper solution. Another solution would be to change the present density of the Nile perch. From an ecological perspective it would be most desirable to deplete the Nile perch completely. However, due to the economic importance of the Nile perch this is not an integrative solution. Therefore, this report proposes to look at the effects of three possible scenarios (see table 1). These scenarios include ‘Business-as-usual (scenario 1)’, Sustainable fishing (MSY) of the Nile perch and combatting eutrophication (scenario 2), and ‘Sustainable fishing (MSY) of the Nile perch without combatting eutrophication (scenario 3)’.
In scenario 1, economic and political decisions remain as they are now which means In which way could eutrophication and biodiversity loss of Lake Victoria be combatted?
little regulating takes place (see policy part as well). Consequently, eventually, the Nile perch population will go extinct due to eutrophication and overfishing. For scenario 2 & 3 the MSY (Maximal Sustainable Yield) of the Nile perch has to be determined. MSY is ‘the greatest quantity that can possibly be removed or obtained from a water body continuously without damaging it’ (United Nations Environment Programme, 2000). It is assumed that species show logistic growth, see figure 2. In practice, the idea of MSY is to maintain the population density to the point of the highest growth rate, which is equal to half of the carrying capacity (figure 2). Ideally, this new number can be maintained indefinitely (Shmoop University, 2013).
However, calculating a MSY is difficult. In 2006, the World Bank calculated that the Nile perch’s MSY in Lake Victoria is between 220,000 tons and 350,000 tons per year. However, a catch of 350,000 ton is too high, since in 2000 annual catch was equal to 303,000 tons and led to overfishing. Optimally, the population size has to be equal to half of the carrying capacity of Lake Victoria. The MSY should be between 220,000 and 250,000. It is evident that the MSY of scenario 2 is higher than the MSY of scenario 3, because the carrying capacity of scenario 2 is higher due to less eutrophication. Therefore, it is estimated that the MSY for scenario 2 is 250,000 tons and for scenario 3 220,000 tons. Furthermore, it is important that these catches are equally distributed over the lake, because otherwise specific sites could still be overfished.
Eutrophication
In scenario 2, eutrophication is combatted as well. Eutrophication could be inhibited by reducing the present algae blooms (Liu et al., 2012). Several techniques are mentioned in the literature, e.g. coagulation–magnetic separation technique and ultrasonic irradiation– coagulation (Liu et al., 2012; Heng et al., 2009). The coagulation-magnetic separation method uses clay particles as magnetic coagulations to remove algae from water bodies rapidly and efficiently. Furthermore, this technique has low production costs en does not harm the environment. However, this method is limited by the amounts of clay which are needed. Moreover algae are not prevented from floating in lakes (Liu et al., 2012). Thus, this method is not ideal for combatting eutrophication in Lake Victoria. The ultrasonic irradiation-coagulation method inhibits eutrophication by breaking down gas vesicles in algae cells and inhibiting photosynthesis. However, a big downside of this method is that is not suitable for large scale algae removal (Heng et al., 2009). In conclusion, both methods can be used to combat eutrophication, though they have their limitations. More research is required about which techniques are most suitable for Lake Victoria.
Combatting eutrophication leads to a slow recovery of all biodiversity in Lake Victoria. In scenario 3, eutrophication is not combatted though. In this case a slow recovery of all
biodiversity is present as well, but the carrying capacity of the lake is lower due to limited oxygen levels.
In conclusion biodiversity could be recovered with MSY and quotas and eutrophication could be inhibited by reducing the present algae blooms.
Table 1: Three different scenarios for the Nile perch in Lake Victoria
Definition of the scenarios, consequences for the Lake Victoria ecosystem in several time steps.
Timestep 1 Timestep 2 Timestep 3 Timestep 4
Scenario 1: Business-as-usual Nile perch populations drop due to overexploitat ion. Haplochromine cichlids recover slightly. Eutrophication is inhibited slightly.
Caridina nilotica will
decrease since their predators,
haplochromine cichlids, have returned.
Nile perch goes extinct. Further recovery of haplochromine cichlids. Eutrophication is inhibited slightly. Haplochromine can recover to some extent. They cannot recover to their previous state (before the introduction of the Nile perch) due to eutrophication. Scenario 2: Sustainable fishing (MSY) of the Nile perch and combatting eutrophication Only slight changes in Nile perch and haplochromi ne cichlid numbers. Nile perch population increases. Resurgence haplochromine species, but depends on how efficiently eutrophication is combatted Nile perch populations remain constant. Haplochromine cichlid population increase. Co-existence between the Nile perch and haplochromine cichlids Sustainable fishing (MSY) of the Nile perch without combatting eutrophication Only slight changes in Nile perch and haplochromi ne cichlid numbers Nile perch population increases a bit. Resurgence of haplochromine cichlids is inhibited by eutrophication The carrying capacity is affected by eutrophication. Nile perch populations and haplochromine cichlids populations remain constant but at a lower level than the scenario in which eutrophication is combatted
Nile perch lives together with haplochromine cichlids
The economic consequences of scenario 1 will be severe. By now it is clear that the business as usual scenario threatens the Nile perch population. According to Ogutu-Ohwayo (1990) the
threats to the Nile perch can lead to the same population collapse as happened in Lake Kyoga earlier. If this happens not only all the economic relevance as discussed in the introduction will be severely harmed, but also up to 30 million people will have economic loss if the indirect dependency on fishery is taken into account (Kaufman, 1992).
If an MSY is set such as in the other scenarios, Nile perch income will decrease at first. However, this situation will be sustainable and therefore more desirable. As mentioned, our estimate of MSY is between 220,000 and 250,000. This is a decrease of 28.6% in the upper limit of the estimate in comparison to the World Bank’s estimate. Based on an estimated 191 million US$ in export value (see footnote for rationale6), this 28.6% decrease in the maximum yield
would lead to an estimated loss of 54.6 million US$, divided over three countries. However, this loss is based on current prices. If the market position of the Nile perch is strong, the excess demand will raise prices and possibly limit economic loss to great extent. Therefore, a thorough analysis of the market positions is needed.
Market Position
First, the market for Nile perch is considered. Since the Nile perch is widespread across the Ethiopian zone, there are lots of potential suppliers, see figure 2.
However, Nile perch supply comes mainly from Lake Victoria. In 2000, the annual worldwide
catch of Nile perch was 302,905 tons. Kenya, Uganda and Tanzania alone accounted for about 100,000; 100,000 and 90,000 tons respectively of this yield (FAO, 2012) effectively making up for more than 95% of global yield. Looking at the Nile perch market, it shows that the Lake Victoria region owns an oligopolistic or dominant position with the other countries, making up the competitive fringe. This in turn implies a strong market position and thus the high current export price and high bargaining power.
6 The export value of Nile Perch from Lake Victoria is estimated as follows. The LVFO estimated that the Nile Perch from the lake accounted for 250 million US$ worth of exports in 2006 (Geheb et al. 2008). However the latest numbers of the FAO show a total world capture of about 287 000 tons, already a 23.5% decline in comparison to the 375 000 tons in 2006 (FAO, 2010). Projecting this decline on the export value would come down to an estimated 191 million US$ by 2010.
If the market for fish is considered on the other hand, the Nile perch can be considered to be fish of superior quality to some consumers. Because the Nile perch is so abundant in Lake Victoria, it has low costs relative to other competitors. Therefore, Lake Victoria can be considered to have a comparative advantage in terms of resources. This in combination with low labor costs results in a competitive advantage. This would be an advantage of the highest category as categorized by Hunt & Morgan (1995) see figure 3.
Figure 3: Competitive position matrix (Hunt & Morgan, 1995)
The poor law enforcement adds to the competitive position by giving the African countries a legal advantage. In absolute advantage theory, this would not even be considered (Hunt & Morgan, 1995). All this accounts to the low relative costs of the Nile perch and thus low opportunity costs. Hence, even though importers (mainly Europe) might have good alternatives, nowhere the opportunity costs would be as low as for fish from Lake Victoria and specifically the Nile perch because of its abundance.
In conclusion, the mere volume of Nile perch traded from Lake Victoria is so large that it provides a strong international bargaining position. The abundance, ease of catch, low labor costs and weak enforcement causes the Nile perch to have a comparative advantage through low opportunity costs. Regarding the Nile perch as a certain quality of fish, makes the comparative advantage in a competitive advantage in the fish market. This all accounts to a very strong bargaining position explained by all main market power models. This would imply high market power and therefore ability to raise prices when the supply drops without significantly harming the demand.
The economic consequences of limiting Nile Perch yield might thus be less severe than estimates based on current prices. Therefore, scenario 2 and 3 might have very limited costs even in the short-run. Scenario 3 is similar to scenario 2, but the MSY will undoubtedly be higher. How much higher cannot rationally be argued with current information. Therefore and
because of the limited information that is available on wastewater treatment in the area, it is not sure if the increased Nile Perch yield will compensate for the costs of decreasing eutrophication. Finally, it should be mentioned that in the latter scenario also livelihood supply from the lake will increase due to increased biodiversity and resilience. This will increase the potential to catch fish for own consumption rather than export. This effect is not expressible in monetary terms, but should not be neglected as socio-economic benefit.
To understand how policy is influenced by several actors, it is necessary to do a stakeholder analysis (see also appendix A).
Fishery-Based Community
The most important actors are the local fishermen of Lake Victoria. A resilient fish-stock is essential for them, because it will provide them a durable income. Furthermore, the lake is essential to safeguard food security, which will be discussed later on.
Pringle (2005b) interviewed several local inhabitants, of which most indicated that they
worried about the biodiversity loss. Some worried about the loss of haplochromine cichlids for cultural and intrinsic reasons. For instance, some thought they were more tasty or that they had medicinal value. The local inhabitants have different opinions about the causes of overexploitation of the Nile perch. Some blamed the macroeconomic instability, which will be discussed later on, which caused crowded fisheries. Others blamed corruption among fisheries authorities, which allowed illegal activities in return for bribes. Overall, most of the interviewed believe that the government should intervene. However, they did not state how these interventions must look like.
BMUs
The fishermen are required to be registered in a Beach Management Unit (BMU). These community-based organizations are introduced by Kenya, Tanzania and Uganda to enable fishermen to involve in fisheries management. (Nunan, et al., 2012).
The BMUs are mainly focused on combatting overexploitation through licenses and law. What are the interests and stakes of the most important stakeholders in the Lake Victoria region? And what is their opinion about solving eutrophication and overexploitation?
Kenya, Tanzania & Uganda
The national actors are the governments of Kenya, Tanzania and Uganda. The ministries which concern fisheries are respectively the Ministry of Fisheries Development Kenya; the Ministry of Livestock Development and Fisheries; the Ministry of Agriculture Animal Industry & Fisheries. Appendix B shows briefly some aspects of each of the three country’s political situation.
Besides the earlier discussed economic benefit, there is also a national security benefit to a stable fish-stock for the states. It is likely that depletion of fish stocks might lead to scarcity conflicts (Homer-Dixon, 1991). Until now, there have been only few conflicts (Canter & Ndwega, 2002).
As shown in Appendix A, the objectives of the ministries of Tanzania and Uganda regarding Lake Victoria, both emphasize the importance of the sustainability of the lake. Kenya’s objectives are more focused on wealth creation.
Remarkably, the websites of the ministries of Tanzania and Uganda barely mention the problems of overexploitation or eutrophication. In the Annual Report of 2010-2011 the Ugandan ministry is focused on licensing gear. However, it wants to stimulate increasing production. A document of the Tanzanian ministry (2011) mentions MSY, but not how to manage it. Notably, the MSY of Nile perch mentioned in the document of the Tanzanian ministry is higher (367,819 ton) than the MSY calculated by the World Bank (2006) (220,000-350,000 ton). This might mean that the Tanzanian government undervalues the problem.
The Kenyan ministry seems to pay more attention to the declining fish-stocks. They mention how the lake can be utilized sustainable. For example, by monitoring and controlling ‘fishing effort, destructive fishing practices & environmental degradation’ and conducting research (Ministry of Fisheries Development, 2012a). In adapting to the declining fish-stock, the
Kenyan ministry sees a lot of opportunities in investing in fish farming (Ministry of Fisheries Development, 2012). The ministry does not mention whether they see eutrophication as a problem or not.
Lake Victoria Fisheries Organization (LVFO)
The LVFO is designed to act as the long-term management body of the lake and its resources. The aim of the LVFO is ‘to harmonise, develop and adopt conservation and management measures for the sustainable utilisation of living resources of Lake Victoria to optimize socio-economic benefits from the basin for the three Partner States’ (LVFO, 2013). It was funded by the Global Environmental Facility (GEF) for 90%. The other 10% comes from an equal contribution of each of the three countries.
The Protocol of Sustainable Development (LVFO, 2003) shows the ideas of the LVFO to combat eutrophication and overexploitation. Article 17 and 18 contains the “polluter-” and “user
pays principle”. The costs recovered from both measures shall be used for management, operations and restorations and for cleaning-up. It also aims to prevent or minimize municipal and mining pollution and by promoting sustainable forestation and agriculture, providing sanitation in the Lake Victoria region and preventing dumping waste from vessels. The water quality has to be monitored and standardized by the three states. It also states the importance of public environmental awareness, public participation and the spreading of knowledge. According to O.C. Mkumbo7, researcher at the LVFO, eutrophication should be solved with
controlling the causes of eutrophication, because this would be more affordable than expensive cleaning techniques.
These policy measures seem to address the problems of eutrophication and overexploitation adequately. However, the LVFO is not able to enforce these measures. Protocols are not binding agreements, therefore, states are not obliged to follow these rules.
Importing Countries & Sponsors
The main importing country of Nile perch from Lake Victoria is Europe (Canter & Ndewga, 2002). Their interest in Lake Victoria is to import fish for the lowest possible price.
The European Union sponsored a ‘Stock Assessment’ program8, which focusses on
commercial species. It ‘would provide information about the size of the fish stock, distribution and movement patterns, population structure, breeding habits, estimates of potential yield, characteristics of fishing gear, catch rates, description of the lake bottom, and updated bathymetric maps. Among the outcomes of the program would be guidelines for fishery conservation, sustainable use, permissible quotas, and proposals for an integrated education program’ (GEF, n.d.a). This reflects that it is beneficial for Europe to invest in the sustainability of
their import product.
Furthermore, other, unknown countries sponsoring Lake Victoria, could have influence as well.
According to the ecological analysis, scenario 2 might be the most preferable. However, this might be difficult to reach politically. This paragraph will outline the main difficulties. Finally, it will discuss possible solutions and the feasibility of these solutions.
7 Derived from e-mail contact on May 14 2013
8 This program was part of a larger project, namely, the Lake Victoria Environmental Project, which was (except for the project sponsored by the European Union) sponsored by the GEF and was ended in 2005 (GEF, n.d.b)
Collective Action Problem
Implementing quotas and cleaning techniques might not work in the current political situation due to the collective action problem. All actors will benefit on the long term from cooperation, but each will act in the anticipation that others will bear the costs of cooperation. If quotas are implemented, it is likely that the fishermen will free-ride. They might not stick to the quotas to maximize their own profit, while the costs of their actions are collective. Sanctions on free-riding behavior might be helpful, because actors are less likely to free-ride because of the potential costs sanctions will give. However, nowadays the fisheries authorities are corrupt, which impede adequate controlling.
What makes it even more difficult is that the lake is situated in three different countries, which are also likely to free-ride. There is no binding agreement which enforce them to bear costs of implementing quotas or cleaning techniques in their country.
Poverty & Food Insecurity
Free-riding behavior among the fishery based community might be increased due to poverty and food insecurity. Poverty hinders environmental knowledge and effective implementation of policy (Gerlak, 2004). The current state of food insecurity causes poor people to overexploit and degrade resources in attempt to survive (Abila, 2003). This has led to the use of devastating gear and illegal fishing. Some of this illegal equipment is already banned, but the controlling is insufficient. For instance, corrupt fisheries authorities allowed the use of illegal nets in return for bribes (Pringleb, 2005).
Financial Needs
To implement techniques to combat eutrophication, financial capabilities are needed. Kenya, Tanzania and Uganda are low income countries9 which will make it difficult for them to make
such an investment on short notice. Furthermore, the implementation of quotas might lead to a slight decrease of the GDP, which causes a decrease in the budget of the states. There are some other sources of investment in the area. Namely, from foreign funds which support environmental policy initiatives in the Victoria Lake area. However, when the money-flow disappears, often programs cannot be continued (Canter & Ndewga, 2002). Mkumbo10,
researcher of the LVFO, stressed the lack of financial capabilities as a main problem. For instance, Kenya, Tanzania and Uganda have Monitor, Control and Surveillance working groups 9 See Appendix B
which are ‘facilitated to ensure compliance to fisheries regulations’. However the three states are ‘limited in resources to provide consistent support to these groups.’
In conclusion, it might not be feasible to create policy to maintain the livelihood of the fishery-based community in the current socio-political situation. The lack of financial needs and ineffective funds make it hard to implement techniques to combat eutrophication. Setting quotas might not help the problem of overexploitation if states and fisheries would try to free-ride. Therefore, it might be useful to create an overarching and independent institution. This could also be done by giving the LVFO more power.
Umbrella Organization
This proposed umbrella organization should contain several features to make it work and to solve eutrophication and overexploitation adequately. First, it should include all mentioned stakeholders. Participation of stakeholders is needed to increase legitimacy and effectiveness of management (Wilson et al., 1999) which is now sometimes lacking in the existing regional administrative institutions (Canter & Ndewga, 2002). Also, it needs to communicate adequately with all the involved stakeholders, to distribute knowledge.
Furthermore, this body could collect and distribute the money-flows from sponsors, because nowadays the funds from foreign sponsors are not allocated efficiently. In doing so, the money could be used for implementing techniques for combating eutrophication. However, it might be less attractive to invest in such an organization, because countries physically wants to see what their money does (Lugo, 2000). To cope with this problem, the organization should be completely transparent.
Also, this body has to create an enforcement and controlling mechanism which includes all stakeholders. To combat corruption, the controlling agents have to be controlled also.
Although it might be the only political instrument to solve the problems of eutrophication and overexploitation, it is not very likely that such an organization will be established. Neither of the countries might be willing to give so much power to this organization.
If, however, such an umbrella organization is created it could use MSY and implement cleaning techniques mentioned earlier. Table 2 shows three scenarios called ‘Business-as-usual’, ‘Sustainable fishing (MSY) of the Nile perch and combatting eutrophication’, and ‘Sustainable fishing (MSY) of the Nile perch without combatting eutrophication’. This table shows that ‘Sustainable fishing (MSY) of the Nile perch and combatting eutrophication might be the most desirable scenario since it provides local fishermen with the highest income in a sustainable way.
Table 2: Three different scenarios for the Nile perch in Lake Victoria
Definition of the scenarios, consequences of certain policy (yellow) on the ecosystem (green) and on socio-economic level (red)
Definition of Scenario
Timestep 1 Timestep 2 Timestep 3 Timestep 4
Scenario 1: Business as usual
Market is leading, states and
institutions will not interfere and follow the wishes of the market
Probably, Europe will not invest in the Lake anymore, because they do not have an interest in the lake anymore. Nile perch populations drop due to overexploitation. Haplochromine cichlids recover slightly. Eutrophication is inhibited slightly. Caridina nilotica
will decrease while their predators, haplochromine cichlids, have returned.
Nile perch goes extinct. Further recovery of haplochromine cichlids. Eutrophication is inhibited slightly. Haplochromine can recover to some extent. They cannot recover to their previous state (before the introduction of the Nile perch) due to
eutrophication. Initially export
increases. Profit accumulates in a small group. This will lead to economic stratification. Poverty, lack of knowledge and malnutrition among fishermen increases Probably, some fishermen will focus on haplochromine cichlids, because the Nile perch industry is become less profitable. Haplochromine cichlids are profitable in local culture. Drop in profit in Nile perch industry. Factories are closing, fishermen fishing Nile perch are unemployed or switch to
haplochromine cichlid market. However, these fish are not for export and the local demand is not high.
The fish industry becomes little. Many jobs disappear due to the localization of the product. It is possible that the haplochromine cichlids will also be overexploited eventually. Scenario 2: Sustainable fishing (MSY) of the Nile perch and combatting eutrophication Quotas and techniques combating eutrophication has been implemented. However, because states and fishermen are likely to free-ride, an independent umbrella
organization has to take care of the compliance of the actors and the effectiveness of investments. To maintain the compliance of quotas, the fish industry has to be
The umbrella organisation has to monitor the level of the Nile perch. If the population gets too big, the quotas could be raised a bit and vice versa. In doing so, the population of the Nile perch and the haplochromine cichlids are more balanced. However, introducing quota’s might lead to increased corruption, because it now pays off to free ride.
After some time, the board of the umbrella organisation should be re-elected, to gain more legitimacy and to prevent corruption.
monitored and controlled closely. To gain legitimacy and knowledge on the situation, all stakeholders have to be represented in this organisation. Therefore, the fisheries authorities have to be controlled closely.
Only slight changes in Nile perch and haplochromine cichlid numbers. Nile perch population increases. Resurgence haplochromine species, but depends on how efficiently eutrophication is combatted Nile perch populations remain constant. Haplochromine cichlid population increase. Co-existence between the Nile perch and haplochromine cichlids
Due to increased policy measures, the comparative
advantage of the Nile perch decreases slightly. Possibly, the Nile perch becomes a less desirable import product.
There will be fewer jobs in the Nile perch industry, because of the quotas. However, the resurgence of the haplochromine cichlids might cause a resurrection of the haplochromine cichlids fisheries, because of their cultural value. Malnutrition will decline, because of the local character of the product.
The balanced coexistence of the Nile perch and the haplochromine cichlids cause a more sustainable livelihood of the local fishery based community. However, the number of jobs is less abundant than in the high
dominance period of the Nile perch. However, the economic stratification is probably less, because the fisheries are not completely dependent on the export market of the Nile perch
Sustainable fishing (MSY) of the Nile perch without combatting eutrophication
Quotas have also been implemented by an umbrella organisation, just as in scenario 2.
Here, the policy measures are quit the same as scenario 2, except the measures will not include eutrophication measures. Furthermore, in keeping the Nile perch population at a sustainable level, the quotas are lower.
After some time, the board of the umbrella organisation should be re-elected, to gain more legitimacy and to prevent corruption.
Over time, the umbrella organization might lose legitimacy, because the fish-stock will not increase much. Due to lack of visible
improvements, it is even more likely that actors will try to free-ride.
in Nile perch and haplochromine cichlid numbers population increases a bit. Resurgence of haplochromine cichlids is inhibited by eutrophication capacity is affected by eutrophication. Nile perch populations and haplochromine cichlids populations remain constant but at a lower level than the scenario in which eutrophication is combatted together with haplochromine cichlids Because of the lower level of the Nile perch, it becomes more likely that actors will try to free-ride. Therefore, the controlling mechanism has to be very effective. However, the chance of corruption of the controlling body will increase. Due to slightly in their comparative advantage (caused by increased regulations) and lower catch-rates the Nile perch industry becomes less lucrative. Poverty will increase, as well as social tensions. The chance on conflicts will increase.
Eventually, this situation might fall back to the business-as-usual scenario
Conclusion
The invasion of the Nile perch caused biodiversity loss and increased eutrophication in Lake Victoria. However, the fishery-based communities cannot make a living without the Nile perch anymore. Therefore, it is strongly recommended that scenario 2 or 3 will be pursued. To combat biodiversity loss and increased eutrophication, policy measures such as setting quotas (at MSY) and implementing cleaning techniques could be taken. However, the current socio-economic situation might impede such measures. The collective action problem; entanglement of the international market; lack of financial need; poverty: they all seem to contribute to the continuing unsustainable use of the lake. For all stakeholders, a stable fish-stock is beneficial. However, due to lack of adequate policy, the stakeholders seem to act in their self-interest without considering the long-term effects of their actions.
The only political solution seem to be the establishment of (or the transformation of the LVFO into) an umbrella organization. This organization could safeguard the lake in several aspects. First, the sponsoring money could be collected and distributed by this organization. Second, it must create an adequate enforcement mechanism to combat free-riding among the individual actors as well as the state actors. Third, it must connect the different stakeholders to enhance knowledge-transfer. Fourth, all the stakeholders must have the opportunity to participate and must be represented adequately to increase the legitimacy. Also, the board must change once in a few years. Fifth, it should implement the policy-measures of the 2nd scenario to
Discussion
One of the main challenges in doing research about Victoria Lake is that it is an interdisciplinary problem. However, there is a clear common ground can be identified between ecology and economy. The term ‘resilience’ is key here. In terms of ecology, a resilient ecosystem is an ecosystem in which species levels fluctuate only slightly and biomass production remains constant over longer time periods. Extended in terms of economy, a resilient ecosystem is an ecosystem which provides only slightly fluctuating yields.
To make economic profits on the long term, a stable ecosystem is needed. To stabilize the Victoria ecosystem MSY could be used. However, since the current level of the Nile perch is unknown, it might be hard to set a MSY. Therefore, more verification of the estimated MSY used in this paper, might increase understanding of severity and scale. Furthermore, the speed with which the Nile perch and other biodiversity returns is unknown.
Our policy recommendations are needed to make effective use of this MSY for a sustainable income for the local fishermen. However, it is questionable these policy recommendations are feasible if the actors recognize that it is the best of the worst options. Fishermen might also ignore future problems, because of the persistence of poverty in the area. Therefore, strong enforcement is required.
Moreover, inherently to the problem is that Lake Victoria is nearly always researched as one unified system. However, it has a huge spatial dimension. As Downing (2012) states: ‘the heterogeneity that characterizes this huge lake implies that drivers of change are having locally-specific consequences. No “one rule fits all” approach can guarantee the efficient and sustainable management for Lake Victoria’s resources’. It is therefore also hard to predict whether stabilizing the ecosystem will benefit provision of livelihood and commercial Nile Perch yield equally in all areas.
It should also be emphasized that the scenarios used do not guarantee certain outcomes and should be realigned and improved along with better availability of information. They do, however, provide useful insights to the socio-economic and ecological consequences of policy and how they are interrelated. To make a definite conclusion whether scenario 2 or 3 will be more desirable, the quantitative effects of the difference in MSY and increased livelihood must be compared with the costs of combatting eutrophication. Therefore a thorough research on the wastewater treatment in the area is needed along with a cost analysis. Furthermore consequences are based on estimates about fish stock, export prices and predicted market position. Accuracy could be increased if more recent data is released.
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