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, published 16 August 2010, doi: 10.1098/rstb.2010.0168365 2010 Phil. Trans. R. Soc. B Halls and Kai LorenzenRobin L. Welcomme, Ian G. Cowx, David Coates, Christophe Béné, Simon Funge-Smith, Ashley Inland capture fisheries

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Phil. Trans. R. Soc. B (2010) 365, 2881–2896

doi:10.1098/rstb.2010.0168

Review

* Autho

While ththe viewand do

One conworld in

Inland capture fisheriesRobin L. Welcomme1,*, Ian G. Cowx2, David Coates3,

Christophe Béné4, Simon Funge-Smith5, Ashley Halls6

and Kai Lorenzen1

1Division of Biology, Imperial College London, Silwood Park, Ascot SL5 7PY, UK2Hull International Fisheries Institute, University of Hull, Hull HU6 7RX, UK

3Secretariat of the Convention on Biological Diversity, 413 Saint Jacques Suite 800,Montreal, Canada H2Y 1N9

4World Fish Center, Penang, Malaysia5FAO Regional Office for Asia and the Pacific, 39 Pra Athit Road, Bangkok 10900, Thailand

6Aquae Sulis Limited (ASL), Midway House, Turleigh, Bradford-on-Avon, Wiltshire BA15 2LR, UK

The reported annual yield from inland capture fisheries in 2008 was over 10 million tonnes,although real catches are probably considerably higher than this. Inland fisheries are extremely com-plex, and in many cases poorly understood. The numerous water bodies and small rivers areinhabited by a wide range of species and several types of fisher community with diversified livelihoodstrategies for whom inland fisheries are extremely important. Many drivers affect the fisheries,including internal fisheries management practices. There are also many drivers from outside thefishery that influence the state and functioning of the environment as well as the social and econ-omic framework within which the fishery is pursued. The drivers affecting the various types ofinland water, rivers, lakes, reservoirs and wetlands may differ, particularly with regard to ecosystemfunction. Many of these depend on land-use practices and demand for water which conflict with thesustainability of the fishery. Climate change is also exacerbating many of these factors. The future ofinland fisheries varies between continents. In Asia and Africa the resources are very intenselyexploited and there is probably little room for expansion; it is here that resources are most atrisk. Inland fisheries are less heavily exploited in South and Central America, and in the Northand South temperate zones inland fisheries are mostly oriented to recreation rather than foodproduction.

Keywords: drivers; inland fisheries; lakes; rivers; social and economic issues; catch trends

1. INTRODUCTIONInland capture fisheries group activities that extractfish and other living organisms from surface watersinland of the coastline. In 2008, inland capture fish-eries produced an estimated 10 million tonnes of fishand crustaceans (FAO Fishstat 2010—see http://www.fao.org/fishery/statistics/software/fishstat/en). Asa valuable source of protein-rich food and employ-ment, inland fisheries deliver nutritional security andincome to hundreds of millions of rural households.Nevertheless, there are serious misperceptions aboutthe magnitude, benefits and sustainability of inlandfisheries resources which limit the effectivenessof national and international policies for theirmanagement and undermine their future.

r for correspondence ([email protected]).

e Government Office for Science commissioned this review,s are those of the author(s), are independent of Government,not constitute Government policy.

tribution of 23 to a Theme Issue ‘Food security: feeding the2050’.

2881

Inland fisheries are dynamic. As economies evolvethe nature of inland fisheries changes (Arlinghauset al. 2002). The importance of high-value inlandrecreational fisheries grows and reliance on fisheriesfor food declines as local economies develop.

Inland fisheries are distinct from marine fisheries intheir nature and in the range of drivers that influencethem. Although commercially intensive fisheriesexist, inland fisheries are generally characterized bysmall-scale/household-based activities. Participationin fisheries is high and the bulk of the catch is con-sumed locally. By-catch is insignificant as practicallyall fish caught are used. This means that their benefitsare widely spread. Inland fisheries are also very diverse,being based on a range of ecosystems whose fishcommunities respond very differently to internal(fisheries-based) and external (natural- and humanecosystem-based) drivers.

One conceptual driver of inland fisheries is thewidespread vision of inevitable demise of inland fish-eries in the face of escalating human impacts, whichis reflected by studies from all continents (Friendet al. 2009). Catches are allegedly falling, species

This journal is # 2010 The Royal Society

http://www.fao.org/fishery/statistics/software/fishstat/enhttp://www.fao.org/fishery/statistics/software/fishstat/enhttp://www.fao.org/fishery/statistics/software/fishstat/enmailto:[email protected]://rstb.royalsocietypublishing.org/

12 000 000

10 000 000

8 000 000

6 000 000

4 000 000

2 000 000

0

year

catc

h (t

onne

s)

1950

1953

1956

1959

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

2007

Figure 1. Global trends in inland fish catch 1950–2008—

including fish, Crustacea and Mollusca, excluding reptilesand mammals (y¼12311x þ 2Eþ06; r2 ¼ 0.960). FromFAO Fishstat database.

2882 R. L. Welcomme et al. Review. Inland capture fisheries


disappearing and many other symptoms of chronicoverfishing are reported. There is an assumption thatoverfishing is to blame, which is influenced by percep-tions derived from marine fisheries. This instils a senseof hopelessness, fuelling neglect and subordination toagricultural, industrial and domestic sectors, particu-larly with respect to competing resources. Thecontribution of wild-caught, inland fish to food secur-ity has been largely ignored, and priorities switched toother sectors. Aquaculture is promoted as the meansto maintain production in the face of this perceiveddecline, a view prominent throughout the tropics andwidely held by aid agencies. The result is a lack ofresources assigned to inland fisheries, a lack of infor-mation and apparent failure to incorporate inlandfisheries’ interests adequately into administrativestructures. In addition, governments and resourcedevelopers see inland fisheries as an impediment totheir desires to expropriate the wealth of the rivers—the transfer of generalized wealth (nutritional security,livelihoods) from powerless people into focused incomestreams that benefit powerful people (Osborne 2010).

Nevertheless, reported catches from inland fisheriesare still rising at a linear rate of about 3 per cent peryear globally (figure 1). There is widespread evidencethat much of the catch from inland fisheries is unrec-orded, partly because of the diffuse and small-scalenature of individual fisheries, the lack of easily defin-able landings, and because much of the catch goesdirectly to domestic consumption (e.g. Welcomme1976, for rivers; Coates 2002, for Asia; Hortle et al.2008, for rice fields; Braimah (in Béné 2007), forVolta Lake; Lymer et al. 2008, for Thailand). TheFood and Agriculture Organization of the UnitedNations (FAO) itself posts caveats about the qualityof the inland fisheries statistics in its SOFIA (TheState of World Fisheries and Aquaculture) reviews(FAO 2002, 2004, 2007, 2009).

These contrasting views of increasing productionand underestimation of the fisheries versus continuingreports of declining fish catches, loss of diversity andlack of potential in individual fisheries are difficultto reconcile because a lack of indicators hinders theformulation of management policy.

This review attempts to clarify some of the issuessurrounding the various types of inland fishery to

Phil. Trans. R. Soc. B (2010)

define their role in food security and in so doingdefines the various drivers operating on inland fish-eries, where drivers are defined as factors influencingyield, changes and sustainability in inland fishresources and fisheries.

2. DRIVERS REGULATING INLAND FISHERIESDemand is the primary driver of almost any humanactivity including inland fisheries, aquaculture andmarine fisheries. It also regulates water management,power supply, mining, forestry, agriculture or any ofthe other influences on inland waters. Demand oper-ates through a series of more immediate drivers asdescribed in table 1. This summarizes the principaldrivers regulating inland fisheries, the mechanismsthrough which they operate, their effects and some sol-utions. Further details on some drivers are discussedin the sections listed.

3. STATE OF KNOWLEDGE OF THE RESOURCE(a) State of statisticsMost countries report their inland fish catch statistics toFAO, where they are accessible through Fishstat (http://www.fao.org/fishery/statistics/software/fishstat/en).

Several weaknesses are apparent in the existingstatistics including:

— inadequate data collections systems;— selective data collection;— double counting of landings;— confusion with aquaculture; and— political pressure.

Most countries do not specify their sampling andreporting procedures so it is difficult to compareresults between countries. As a result many of thenominal catch statistics must be considered as unreli-able and should not be used unless they arereconciled with other sources of information (Coates2002). Where the errors and biases are consideredconstant, the statistics may be used to indicate trends(e.g. Lymer & Funge-Smith 2009).

(b) Estimates of trends in inland fish catchFAO nominal fish catch statistics reported a total catchof 10 220 499 tonnes in 2008 for the inland waters ofthe world. Catches have risen steadily at about 3.05per cent per year since the beginning of FAO statisticalrecords in 1950 (figure 1).

Trends in catch by continent suggest the mainincreases are associated with Asia and Africa, and to alesser extent the Americas (figure 2). Table 2 showspercentage contribution by continent and the growthrate in catch over the last 10 years by continent. Thedeclines in catch noted in Europe and North Americacan be attributed to the progressively greater use ofinland fish resources for recreational fisheries.

(c) State of exploitationMost inland fisheries are multi-species, multi-gear innature, so standard assessment models and conceptsof overfishing are inappropriate and can be applied

http://www.fao.org/fishery/statistics/software/fishstat/enhttp://www.fao.org/fishery/statistics/software/fishstat/enhttp://www.fao.org/fishery/statistics/software/fishstat/enhttp://rstb.royalsocietypublishing.org/

Tab

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Review. Inland capture fisheries R. L. Welcomme et al. 2883



http://rstb.royalsocietypublishing.org/

Tab

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1950

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Figure 2. Trends in catch by continent 1950–2008 (darkblue, Asia; brown, Africa; green, Americas; violet, Europe;light blue, Oceania; yellow, ex USSR territories). From FAO

Fishstat database. N.B. The FAO dataset is discontinuousfor the old USSR countries which were reported as a group(other) until 1987. After that date they were split into individ-ual reports. Here the catches from the old USSR includingRussia were combined with those of Europe for a continuous

dataset—inland water catches from the former Asian USSRrepublics are now generally negligible.



only in a few lakes where a limited number of speciesare exploited by a homogeneous fishery. Instead, thefishing-down process that operates in many inlandwaters suggests that the main indicator of heavy fishingis a reduction of mean size (and age) of the fish landed.In many areas of the tropics, the mean size and age ofthe catch have reduced progressively over the years,until in some cases the major part of the catch consistsof fish in the first year of life (see, for example, Lae1995; Halls et al. 1999). In addition, fisher numbershave increased throughout Asia and Africa (see FAOdatabase on fishermen numbers—http://www.fao.org/fishery/statistics/programme/3,1,1/en). These factorsindicate that most inland fisheries in these continentsare heavily fished to a degree that substantially altersthe species composition, abundance and ecology ofthe fish communities, and that there is probably littleroom for any substantial increases in catch. Fishingpressures in South America do not appear to havereached these levels, as catches still include largespecies, and there is probably some room for increase.In other areas, catches appear to be maintained bystocking programmes. In the temperate zone, inlandfisheries resources seem to be increasingly orientedtowards recreation and conservation (Arlinghauset al. 2002; Cowx et al. 2010), although there is grow-ing evidence that recreational fisheries are havingsignificant impacts of stocks both from fishing pressureand stock dynamics (Cooke & Cowx 2004, 2006).

(d) Importance of inland fisheriesFish from all sources form the major single source ofanimal protein worldwide, accounting for over one-third (36.58%) of global production in 2007(table 3). Based on current statistical information,inland fisheries account for 2.36 per cent of animalprotein sources. This figure is very likely to be under-estimated as compared with their 6.8 per centcontribution to the world total fish production, asabout 90 per cent of fish from inland capture is for


human consumption as opposed to marine fisherieswhere a substantial amount goes for fishmeal.

Fish from inland waters can be extremely importantto local food security as compared with other sourcesof animal protein. For example, the Lower Mekongbasin has a population of more than 60 millionpeople. Inland capture fisheries yield in the region isabout 2 million tonnes per year and 1 million tonnesof fish is equivalent to 1 200 000 big buffaloes or16–17 million pigs. In Laos inland fish contributes29 kg per person per year (48% of animal protein)and in Cambodia 37 kg per person per year (79% ofanimal protein; Hortle 2007).

4. KEY FEATURES OF INLAND WATERSFish inhabit most inland water ecosystems. The ecol-ogy of the many species, and to a large extent themethods by which they are exploited, are determinedby the ecosystem and habitat characteristics. The dri-vers operate in different ways and diverse approachesneed to be taken to their management. The maintypes of inland waters are as follows.

(a) RiversRivers are open, linear systems with numerous smallheadwater streams that depend mainly on externalnutrient inputs. In headwaters, food webs are basedon organic matter that is progressively degraded byinvertebrate and micro-organism activity along thecourse of the channel (river continuum concept;Vannote et al. 1980). Significant drivers are thedegree of deforestation, and agriculture practice inthe vicinity of the river. In lowland rivers, nutrientdynamics involve material deposited on the floodplain.There is a seasonal shift in ecology associated withseasonal flooding (the flood pulse concept; Junk et al.1989). Floodplains are of particular importance tothe breeding, feeding and growth of many species offish and catches from any particular system are closelycorrelated to the degree to which the floodplains wereflooded in preceding seasons.

(b) LakesLakes are closed systems consisting of a defined bodyof water. Lake ecology is stable relative to rivers.Some lakes may become severely reduced in area oreven dry out when flows are reduced, as, for example,Lake Chad or the Aral Sea.

Lakes are classified according to their nutrient rich-ness—oligotrophic lakes being the lowest in nutrientsand the least productive, and eutrophic lakes beinghigh in nutrients and highly productive. Changes inwater quality are the major driver of lake ecology andshifts in water transparency, dissolved oxygen regimesand resident organisms occur with nutrient enrich-ment (eutrophication). Oligotrophication, reversionto lower nutrient status, may occur if nutrientinputs are reduced. Pollution from other sources,and sedimentation, are additional pressures.

(c) ReservoirsReservoirs, especially those with short retention times,are sensitive to changes in flow regime in inflowing

http://www.fao.org/fishery/statistics/programme/3,1,1/enhttp://www.fao.org/fishery/statistics/programme/3,1,1/enhttp://www.fao.org/fishery/statistics/programme/3,1,1/enhttp://rstb.royalsocietypublishing.org/

Table 2. Inland water catcha and relative contribution (percentage) for each continent to the global inland water catch in

2008 and the percentage growth rate in inland fisheries catches over the last 10 years. From FAO FishStat (2010).

continent 2008 (tonnes) relative contribution (%)mean % per year movement over last10 years (1998–2008)

global total 10 220 451 100 2.73Asia 6 786 534 66.40 3.48Africa 2 502 570 24.49 2.29America South 378 484 3.70 1.09Europe 357 057 3.49 21.10America North and central 178 068 1.74 21.41Oceania 17 786 0.17 21.24

aincluding all catch.

Table 3. Global production of animal protein by source

according to Faostat. N.B. Inland fish production (initalics) is for comparison and does not contribute to thetable total.

protein sourceglobal production2007 (tonnes) %

fish (all sources) 156 371 774 36.58pig meat 99 211 931 23.38

chicken meat 75 826 354 17.87cattle meat 59 851 860 14.10inland fish 10 034 537 2.36sheep meat 8 303 867 1.96turkey meat 5 868 167 1.38

goat meat 4 828 237 1.1414 others (each contributing

less that 1%)15 258 112 3.59

total 424 415 484 100



rivers and may become severely reduced in area attimes when the dam is opened for electricity gener-ation or water abstraction. Rapid fluctuations inwater level (daily due to hydropeaking) are a particularproblem in reservoirs, so one of the main drivers ofreservoir ecology is the nature of the dam operation.

(d) WetlandsWetlands are primarily extensive shallow swampy areasoften associated with river or lake systems as riparianfloodlands. They often vary in area seasonally anddepend on local rainfall, discharge from inflowingrivers, groundwater or on rising lake levels. They areusually very productive and support populations offish that are highly adapted to the generally difficultenvironmental conditions of wetland habitats. Wet-lands are one of the most threatened of environments.

Rice fields constitute man-made, temporary wet-lands and account for over half of total wetland areain Asia. They are colonized by fish during the wetseason and support high levels of fisheries production(Nguyen Khoa et al. 2005; Hortle et al. 2008).

(e) Coastal transitional watersTransitional waters include river estuaries, coastaldeltas, coastal lagoons and inland mangrove systems.They are often integrated into complexes of floodablecoastal wetland, and permanent lagoons and channels.


The ecology of the fishes depends on salinity andthe main direct drivers of fisheries production arechanges in flow regimes (freshwater input) leading toingress of saline marine waters, pollution, and landreclamation and associated loss of wetlands, all leadingto reduced fishery production.

(f) Magnitude of area of inland water resourcesThe relative magnitude of the main categories offresh waters (excluding transitional waters) in thevarious continents is shown in table 4. Globally,there are 304 million natural lakes that cover4.2 million km2 (Downing & Duarte 2009). Theland area covered by constructed lakes and impound-ments is 335 000 km2 (77 million impoundments);76 830 km2 of this area are farm ponds. The figuresfor wetland area are considered underestimates.

5. KEY FEATURES OF INLAND FISHAND FISHERIES(a) Characteristics of fish assemblagesin inland waters

(i) Numbers of fish speciesFish assemblages in inland and coastal waters tend tobe highly complex. In rivers the number of species isstrongly correlated with basin area (Oberdorff et al.1995). The number of species in individual riversystems ranges from tens in small basins to over 1000in large systems such as the Amazon or Mekong. Inlakes, the number of species is also broadly correlatedwith basin area (Amarasinghe & Welcomme 2002).

(ii) Responses of fish assemblages to fishing pressureMulti-species, multi-gear fish assemblages and fish-eries in inland waters respond to drivers such asheavy fishing or use of illegal methods according to amodel known as the fishing-down process (Welcomme1999). This predicts that, with increases in fishingpressure (effort), the larger individuals and specieswill be successively reduced and even lost from thefishery (overfishing of species) until only the smallerspecies remain to form the basis for the fishery.Because smaller species are generally more biologicallyproductive, and many of the larger species are fish-eating predators, production of the fish assemblageas a whole responds, so the level of catch remains thesame over a considerable range of fishing pressure.


Table 4. Distribution by continent of surface freshwater resources. Note the figures for lakes, reservoirs and rivers are given

in cubic kilometres whereas measures of yield are generally given relative to hectares.

Africa Europe Asia Oceania N. America S. America

large lakes (km3) 30 000 2027 27 782 154 25 623 913

rivers (km3) 195 80 565 25 250 1000reservoirs (km3) 1240 422 1350 38 950 286wetlands (marshes, swamps, mires,

lagoons, floodplains, km2)341 000 ‘Eurasia’ 2 075 000 (925 000

natural wetlands, 1150 rice fields)4000 180 000 1 232 000



Excessive fishing may reduce the functioning of thefish community (community overfishing).

(b) Fishing gearFishers respond to the diversity of habitats and thelarge number of species, life stages and behaviour,and seasonality of the systems by developing a rangeof gears adapted to the capture of all species and lifestages throughout the year. Up to 150 different gearsare described by Deap et al. (2003) for a large riversuch as the Mekong.

6. FISHING AND PEOPLE(a) Inland fisheries as part of a diversifiedlivelihood strategy

Inland fisheries differ fundamentally from their coastalcounterparts in the very diversified and complex formsthat inland fishing can take within the livelihood of thefisher households. Indeed, for many local populations,inland fishing is only one economic element withinthe diversified matrix of activities that constitute theirlivelihoods strategy.

(b) Socio-economic importanceof inland fisheries

The socio-economic importance of inland fisheriesand their role in rural economies in developingcountries are often underestimated. Inland fisherieshave been perceived as ‘backward, informal and mar-ginal’ economic activities (Platteau 1989) and arepoorly integrated into national or local decision-making processes (Dugan 2005; Sneddon & Fox2007; Sugunan et al. 2007).

Recent studies show that the true situation may bevery different. It was estimated that more than 56million people were directly involved in inland fisheriesin the developing world in 2009 (BNP 2009). Thisnumber is larger than the estimated 50 millionpeople who depend on the same activities in coastalareas.

The great majority of inland fisherfolk are engagedin the ‘small-scale’ sector, which ranges from family-based artisanal units operating with or withoutdugout canoes in small ponds or lakes, or along tribu-taries or larger river channels, to commercialenterprises with motorized and well-equipped boatsfishing in larger lakes and reservoirs. Furthermore,the vast majority of the households that depend oninland fisheries are farmers or fisher–farmers whohave traditionally engaged in seasonal farming andfishing.


The inland fisheries post-harvest sector generatesparticularly important economic opportunities forwomen and it is estimated that 54 per cent of thepeople involved in small-scale fisheries are women.

(c) Role of small-scale inland fisheries(i) Food and nutritional securityFish play a particularly important role in improvingthe nutrition of millions of people in the world(table 3). Not only are they a source of protein butthey also provide vitamins, minerals, fatty acids andother micronutrients essential to a healthy diet (Rooset al. 2007a,b). Small-scale fisheries play a criticalrole in the food security of producers and theirfamilies, but also provide for other consumers.Inland fish is traded far afield from local ‘inland’ mar-kets, and a substantial part of the catch may beconsumed by coastal urban dwellers.

(ii) Cash income generationOne of the most important contributions to the liveli-hood of millions of people is the role of inland fisheriesas a source of cash for households, not only for familiesof full-time fishers but for an unexpectedly largenumber of rural households that live close to waterbodies and engage in fishing activities for only a fewweeks or few months each year (e.g. table 5).

Fishing in floodplains or along rivers or lake can beoperated all-year-round and offers households thepossibility to generate revenues on an almost dailybasis. Fishing plays a critical role as a ‘bank in thewater’ (Béné et al. 2009) for local populations thatlargely rely on this activity to access cash quickly.

(iii) Labour buffer functionThe most critical contribution of inland fisheries is itsrole in the provision of labour for unskilled workerswho often appear to rely heavily on fishing and relatedactivities such as fish processing for their livelihood.The common pool nature of small-scale fisheriesallows poor people to engage more heavily in thisactivity to sustain their lives.

(iv) Safety net function and coping strategyin subsistence systemSmall-scale fisheries also play a role as a ‘safety-net’ inthat fishing can provide alternative or additionalsources of income, employment and food for thepoor and near-poor households whose livelihoodshave been temporarily reduced or affected by unex-pected shocks or in periods of individual or collectiveeconomic crisis.


Table 5. Contribution of fishery to households’ cash income (US$/household/year) in different parts of the Zambezi basin,

compared with other activities (% of total household income). From Turpie et al. (1999).

Barotse floodplain Caprivi-Chobe wetlands Lower Shire wetlands Zambezi delta

cattle 120 422 31 0

crops 91 219 298 121fish 180 (43%) 324 (28%) 56 (13%) 100 (39%)wild animals 6 49 1 0.4wild plants 24 121 48 29wild foods 0 11 7 4

clay 2 0 8 0.1



(v) Rent and FOREX generationThe capacity of inland fisheries to generate rent andforeign exchange earnings (Valdimarsson 2003) is lim-ited to very few fisheries, the best example being theLake Victoria Nile perch fishery that generates morethan US$250 million annually for the three ripariancountries (Cowx 2005).

7. DRIVERS EXTERNAL TO THE FISHERYInland waters have suffered the most intense human-induced impacts of all ecosystems over the past 100years. As a consequence, freshwater fishes havebecome threatened by a wide array of factorsthat seem to be the underlying cause of the declineof many fisheries. These issues can be brokendown into fishery-related and environment- orwatershed-related problems.

(a) Fishery-related issuesExploitation is one of the key drivers affecting inlandfisheries. In developed countries, inland fisheries areexploited mainly by recreational fisheries. In develop-ing countries, exploitation is largely for food(Welcomme 2001), although recreational fishing isdeveloping as part of the tourism sector (Cooke &Cowx 2004).

The general effects of heavy fishing pressure are toreduce the abundance of desired species (reducingthe value of the catch) and affect the fish populationor community structures (size and species). Whileoverall production from the fishery is generally notcompromised, the quality and value of the fisheriesshift towards lower-value products that are consumedlocally. An important aspect of many inland fisheriesis therefore not sustainability of the total catches butdetermining what kind of fishery management aimsto achieve. The trade-offs between sustaining catchesof larger higher-value species versus supplying cheaperfish to the generally more numerous underprivileged(Cowx 1998a) are discussed in §8a.

Direct conflicts often exist between commercial andrecreational fishing because they exploit the sameresource base, although many studies indicate thatcommercial and recreational fisheries can coexist (seeHickley & Tompkins 1998). When commercial andrecreational fisheries compete, the allocation of theharvest is generally in favour of recreational fishingin industrialized nations; the opposite is true fordeveloping countries.


(b) Environmental and watershed-related issuesThe greatest threats to inland fisheries come from out-side the fisheries sector. Aquatic resources are subjectto numerous anthropogenic perturbations (Cowx1994; Cowx & Welcomme 1998), which have causedshifts in the status of the fisheries and a general declinein the yield. Fisheries are not generally considered ofsufficiently high priority or value relative to the compet-ing uses, and thus suffer in the face of economicallyand socially higher priorities, such as agriculture,hydroelectric power production or water sports.

The major drivers external to the fishery are listedin table 1 and include:

— modification of environmental form and functionsimplifying the environment and eliminatingcritical habitats;

— dams and barrages blocking passage to fish andmodifying flows;

— land recovery, drainage, flood protection reducingflooded area and eliminating critical wetlandhabitats;

— industrial, agricultural and urban water abstractionaltering the amount and timing of flows;

— land-use practices, including forestry, changingrun-off and sedimentation;

— degradation of water quality through pollution andeutrophication; and

— recreational use and navigation.

8. GOVERNANCE, INSTITUTIONS, MANAGEMENTSYSTEMS AND STRATEGIES(a) Governance and access regimesThere is a wide range of access regimes and fishingright systems in inland fisheries. In most cases theyremain public resources but responsibilities for man-agement are increasingly being devolved to privateindividuals or groups/local communities.

The claim that small-scale fisheries in the develop-ing world are ‘open access’ resources (e.g. Panayotou1982; Bailey & Jentoft 1990; Machena & Kwaramba1997) does not reflect reality. Very few inland fisheriesare de facto open access. Most are linked to some formof management system at the local/community level(Fay 1989; Thomas 1996; Béné et al. 2003).

(b) Current difficulties for the managementof inland fisheries

The diversity of inland fisheries is to be found in theirecology as well as the social and institutional settings


Table 6. Different strategies for management of inland

waters for fisheries in developed and developing countries.From Welcomme (2000).

developed(temperate) developing (tropical)

objectives conservation/preservation

provision of food

recreation incomemechanisms recreational fisheries (commercial) food

fisherieshabitat rehabilitation habitat modificationenvironmentally-

sound stockingenhancement, e.g.

through intense

stockingintensive

aquacultureextensive, integrated,

rural aquacultureeconomic capital-intensive labour-intensive



under which they operate. There is considerableuncertainty in the processes that govern theirdynamics. Because small-scale fisheries are affectedmainly by external processes, unpredictable insti-tutional and policy environments are sources ofconstant uncertainty and threat. Water allocationpolicy and investments, water flows, pollution and cli-matic variability are dominant drivers of many inlandfishery systems. Faced with such challenges, conven-tional fisheries management has generally beenirrelevant as a basis for sustainable development.

(c) Management strategiesInland fisheries tend to evolve along a cline from initialemphasis on food production, through recreation, toaesthetic and nature conservation (Arlinghaus et al.2002; Cowx et al. 2010). The position of any fisheryalong this trajectory varies most markedly betweendeveloped and developing countries (table 6). Fish-eries management in industrialized countries focusesalmost exclusively on recreation and conservation,whereas developing countries still focus on food secur-ity, although the emphases on recreational fisheries(Cowx 2002) and conservation (Collares-Pereiraet al. 2002) are increasing as a result of globalization(Cowx et al. 2010).

Fisheries management can be broken down intothree major domains: management of the fish assem-blages; management of the fishery; and managementof the environment. Which of these domains predomi-nates depends on the type and location of the fishery.Natural lake fisheries, for example, tend to be regu-lated mainly by management of the fishery;enhanced fisheries in dams and reservoirs tend to con-centrate more on management of the fish; and fisheriesin rivers and estuaries are predominantly managedthrough control of the environment.

(i) Management of the fishA variety of techniques are used to improve productionof fish species favoured by commercial or recreationinterests, to make up for shortfalls in production aris-ing from overfishing or environmental change, toenhance the potential yield from a particular water


body or for conservation initiatives (Cowx 1994,1998b; Welcomme & Bartley 1998). They include:

— stocking natural waters to improve recruitment,and bias fish assemblage structure;

— stocking to maintain productive species;— introduction of new species to exploit underused

parts of the food chain or habitats;— elimination of unwanted species; and— construction of biased and selected faunas.

(ii) Management of the fisheryIn addition to direct intervention on the fish popu-lations/communities, fisheries are usually controlledby enforcement of various regulatory constraints toprevent the overexploitation of the resources andmaintain a suitable stock structure (table 7). Irrespec-tive of the regulation measures, the fundamentalproblem usually lies with intense fishing pressurebrought about by open access to the fishery resources.Restricting access is, however, not a simple solutionbecause many fisheries are multi-gear, multi-speciesand complicated by social issues, such as traditionaluse rights and family obligations.

In many fisheries in the world, management iswholly under the control of a centralized authoritythat regulates effort, through access or catch regu-lations. This can lead to social inequity by denyingaccess to some. Centralized authorities have alsoproved largely ineffective because they cannot respondto the fluctuating nature of inland fishery resourcesand enforce regulations in highly dispersed, multi-species, multi-gear fisheries across huge areas. Thereis a growing tendency worldwide to charge fishingcommunities with the management and improvementof their resource (Welcomme 2000; §7a).

(iii) Management of the environmentMajor challenges for inland fisheries managers andstakeholders relative to the environment are: (i) todefend the interests of the fisheries stakeholders byinteracting and making alliances with other interestedparties; (ii) to seek to limit damage to aquatic ecosys-tems; and (iii) to promote rehabilitation activities. Anumber of key strategies are promoted, usually toaddress one or several problems, which may begrouped under five main actions:

— reserves/refuge areas;— pollution control and prevention;— environmental flows;— freedom of passage; and— rehabilitation of degraded habitats.

(iv) Special needs of international river/lake basinsMany rivers and lake basins lie within the territories ofmore than one country. Fish often migrate from onecountry to another for breeding, feeding or refuge.Human activities in one country can also affect thoseof others. More seriously, impacts of pollution, waterabstraction and damming for power generation andirrigation are transmitted downstream in river basins,


Table 7. Comparison of tools to regulate fishing practices in commercial and recreational inland fisheries. From Cooke &

Cowx (2006).

regulatory tool commercial fisheries recreational fisheries

closed areas protected areas and nursery habitats protected areas and nursery habitats

closed season linked to spawning periods or vulnerable periods duringmigration

usually linked to spawning periods

catch limit occasionally quotas bag limiteffort regulation licensing partially in some jurisdictions (e.g. UK)type of gear to minimize damage to stocks through, for example, mesh size

or highly efficient, destructive gears

usually only in specialist fisheries

size of fish minimum size limits usually linked to size at maturity minimum size retained in some fisheriesspecies of fish occasionally quotas at specific times and in specific places



potentially damaging fish stocks, or in the latter caseblocking migratory routes for fish.

Common approaches need to be adopted for theirmanagement using the ecosystems (river or lakebasin) approach. Many international mechanisms forsuch collaboration exist in the form of river and lakebasin commissions, but these usually address develop-mental issues such as water supply, power generationor navigation, and rarely consider fisheries.

(v) Management modelsA number of models have been developed to assist inthe assessment and management of inland fishresources. Many of these were derived from modelsdesigned for marine fisheries on unit stocks. Some ofthese are adequate for the management of single-species fisheries in large lakes such as the Nile perchfishery of Lake Victoria, but on the whole do not per-form satisfactorily in the more diffuse multi-speciesmulti-gear fisheries of rivers and floodplains. As a con-sequence, a series of models have been derived todescribe the performance of exploited fish assem-blages. These are needed not only for the assessmentand management of the fishery itself but must provideinformation on the impacts of any environmentalchanges on the fishery, especially riparian wetlanddrainage and damming. In view of the continuingdemands on water for uses other than fisheries,models that guide the setting of discharges for environ-mental flows (see §7c) are especially urgent. Theproblem is that, although such models are appropriateand useful, it is difficult to act on the managementadvice they generate because of poor managementand enforcement capacity.

(d) Valuation of fisheries(i) Attempts at valuationIt is widely acknowledged that in most parts of Africaand Latin America, and to a lesser extent in Asia, it isextremely difficult to make any accurate and up-to-date assessment of the economic value of small-scalefisheries activities. A large number of recent worksunderline the high potentials of small-scale fishingactivities for economic development (e.g. Cowx et al.2004; Neiland & Béné 2006; Sugunan et al. 2007).

Neiland & Béné (2006) attempted to address thelack of valuation for inland fisheries and some studiesconfirm the substantial values of inland fisheries. For


instance, various attempts to value the Mekong fish-eries have been reviewed by Hortle (2009), andBaran et al. (2007) estimated that the commercialvalue of the Lower Mekong fisheries is worth betweenUS$550 120 and US$1 796 560 per year at firstlanding.

One of the major limitations of the various studies isthat they often only account for the monetary value ofthe catch on local markets. In fact the actual value ofthese small-scale fisheries goes far beyond thismarket value, highlighting in particular the criticalrole that the sector plays in terms of food security,sources of cash and employment for resource-poorlocal communities in remote rural areas (e.g. Bénéet al. 2009).

(ii) Recreational fisheriesRecreational fisheries are the dominant use of fishresources in inland waters in the North and Southtemperate zones, particularly Europe, North Americaand Australia. The sector is also experiencing explo-sive development in many transitional economies inAsia and Latin America and a few countries inSouthern Africa (Angola, South Africa, Zambia).The economic potential of recreational fisheries isvery high. Direct income is generated from the saleof fishing licences, which may have to be paid to theowner of the fishing rights whether this is a public orprivate entity. The sector also has a considerable sec-ondary income generating effect through producersand sellers of fishing equipment, bait providers, boatrenters, guides, lodge owners, travel agencies, restau-rants, boat constructors, producers of books,magazines, documentaries and digital information onsports fishing, and producers of stocking material.

(iii) Ecosystem services associated with inland fisheriesA number of ecosystem services are associated withinland water fisheries as defined by Holmlund &Hammer (1999) and the United Nations 2004 Millen-nium Ecosystem Assessment. Fisheries managementstrategies should aim to conserve the full range ofservices if possible, although in many circumstancessome will be awarded higher priority than others.

(iv) Energy useInland fisheries are characterized by a relatively lowdependence on fossil fuels so the carbon footprint of


raceways

cages

completely fed and aerated ponds

fertilized and fed ponds

fertilized ponds

bursh parks and pens

heavily stocked fertilized (2000–3000 ha–1)

extensive stocked unfertilized (500–2000 ha–1)

natural production with stocking (



captive breeding). All aquaculture was originally basedon wild stocks and was only liberated by the develop-ment of artificial breeding techniques in the 1950s.

Capture-based and self-recruiting aquacultureremain strongly dependent on the productivity ofwild fish stocks and are only viable in the longerterm where fishing pressure on the fry remainswithin the limits imposed by the ability of wild popu-lations to compensate for removal of early life stagesthrough density-dependent processes.

(d) Can aquaculture substitutefor declining capture fisheries?

Aquaculture development is often promoted to miti-gate for real or perceived declines in inland fisheriesand their contribution to rural livelihoods. However,fisheries and aquaculture are very different activities,and it is not usually possible to simply replace fisherieswith aquaculture. The main reasons for this are:

— Fisheries exploit common pool resources. Theirexploitation requires access to the water body andresource, but does not require land and can operatewith very little capital. Aquaculture is the farming ofaquatic organisms owned privately, and it requiresprivate rights to land or an area of water, and sub-stantial capital, especially if production is intensified.

— Aquaculture is a farming activity, and requiresinputs such as seed fish, feed and/or fertilizer, ifyields are to be raised over and above ‘natural’levels.

— Fisheries present livelihood options for a widerange of people, but particularly the poor.Aquaculture is often taken up predominantly bybetter-off households, although successful uptakeby the poor is possible.

— To develop, aquaculture needs supply industries,in particular, seed production and distributionnetworks. Where such networks do not exist,substantial support may be required for theirdevelopment.

— Aquaculture produces a small number of mostlylarge-bodied species that provide high qualityprotein, but may not replace the diversity of micro-nutrients (especially calcium and vitamin A)available from small, wild fish eaten whole.

— There are cultural barriers to the development ofaquaculture and its uptake by particular groups.For example, because aquaculture is essentially afarming activity, it is rarely taken up by full-timefishers.

For these reasons, it must not be assumed that aqua-culture development is necessarily a suitablecompensation measure for loss of fisheries yield.

10. POTENTIAL EFFECTS OF CLIMATE CHANGE(ADAPTED FROM HALLS 2009)Climate change is likely to affect inland fisheriesthrough several mechanisms.

(a) TemperatureHigher temperatures reduce oxygen solubility in waterbut can raise the oxygen and food intake demand of


fish as their metabolic rates are raised. Associatedrises in gill ventilation rates can lead to increaseduptake of aquatic pollutants, potentially renderingthe flesh unfit for human consumption. Higher watertemperatures can also favour the survival of parasitesand bacteria. All these responses combine to poten-tially reduce fish survival, growth and reproductivesuccess both in wild populations and aquaculture sys-tems (Ficke et al. 2007). Similarly, many species intemperate regions have characteristic temperatureranges in which they live and breed and rises in temp-erature may result in species being displaced to higherlatitudes to be replaced by species preferring highertemperatures.

(b) Hydrological impactsIn rivers, increasing flows during the flood season willtranslate to more extensive and prolonged floodplaininundation, potentially increasing overall system pro-ductivity including the fish component (Welcomme1985; Junk et al. 1989). Longer, more extensive floodsare likely to provide greater and more prolonged feedingopportunities for fish. Improved growth can favour sur-vival and reproductive potential (fecundity). Changes tothe timing of flows also have the potential to disruptspawning behaviour (Welcomme & Halls 2001).

The dry season is a period of great stress to manyriver fish species arising from diminished feedingopportunities and water quality, and elevated risk ofpredation or capture. Fish survival during this periodis therefore likely to be density-dependent. Increasedprecipitation and water availability during this periodmight favour fish survival and ultimately exploitablebiomass, while drier conditions would have theconverse effect (Halls & Welcomme 2004).

The combination of reductions in river flow and sealevel rise may change salinity profiles in river deltasand lead to greater upstream salinity intrusion.These changes may displace stenohaline (narrow sal-inity tolerance) species further upstream and increasethe upstream range and biomass of euryhaline (widesalinity tolerance) species, including those thatdepend upon brackish water environments to completetheir life cycles.

Perhaps the greatest impact will be in the conver-sion of snow- and glacier-fed rivers to rain-fed riversas the permanent ice in many mountain regions iseroded. This will change the hydrological character-istics of such rivers fundamentally, altering theirseasonality and the evenness of the food regimes.

(c) Watershed/basin level impactsCareful consideration will have to be given to bothplanned and autonomous adaptive coping strategiespursued by the agricultural sector. Less predictableflooding patterns and reductions in dry season flowsmay force small-scale farmers to build makeshiftlevees to protect their crops from flood damage andto rely increasingly on surface water bodies to meettheir irrigation needs. Planned adaptation may favourthe construction of large-scale storage reservoirs,flood control embankments and irrigation schemeswith an associated increase in withdrawal of water




from the aquatic ecosystems, which impact negativelyon the fisheries sector by obstructing fish migrationsand diminishing dry season habitat availability andquality (Halls et al. 1998, 1999).

11. FUTURE OF INLAND FISHERIESFisheries in Asia are very heavily exploited and havevery little apparent room for expansion by better man-agement. In Africa fishing pressure, althoughincreasing, is still below the level experienced in Asiaso there still may be some potential for expansion.The economic value of small-scale fisheries in Africacould be doubled or tripled simply by improving post-harvest processing techniques. In Latin America, fish-eries appear relatively less heavily exploited than inAsia, with few signs of fishing down at the communitylevel, although some individual stocks are underpressure. Inland fish resources in Europe, North Amer-ica and Australia are exploited more for recreationalthan consumptive purposes, and often managed tomeet conservation objectives (Cowx et al. 2010). As aresult production for food is declining.

The significance of current reported catches is diffi-cult to assess. It is assumed that actual catches havebeen at a maximum level for some time, althoughreal increases are still occurring in some fisheries.Increases in reported catch are mainly because ofimproved reporting of hitherto unrecorded sources ofinland fish, such as small-scale artisanal and subsis-tence yields, or yields from rice fields. It isimpossible to predict at what level reported andactual catches will merge, if ever, although it is clearthat present actual production exceeds the 10 milliontonnes estimate by a large margin.

Better understanding of the significance of inlandfisheries resource may influence the direction ofgeneral development policies for aquatic systems, inparticular in relation to further hydropower and irriga-tion investments. The greatest risk, particularly inrivers, coastal lagoons and estuaries and river-drivenlakes, is modification of flow regimes by water abstrac-tions and power generation, principally throughdamming. Climate change is likely to exacerbate thesituation arising from adaptive strategies such asflood control, and increasing demand for water for irri-gated agriculture. The risks of losing catch are alsoincreased by other forms of environmental damagesuch as draining of seasonal riparian wetlands andriver channelization. The assumption that betteridentification of the role of inland fisheries in liveli-hoods and food security would result in the sector’sneeds being considered when planning new civilworks on rivers has so far been unjustified. As aresult, losses of inland fishery production can beanticipated in many rivers, lakes and wetlands.

One method to mitigate for this loss is to developimproved fishery enhancements in the inland watersthat remain after the present wave of modifications.Fishery enhancement was popular in the 1980–1990s and achieved notable successes in increasinginland fish production in many countries. Unfortu-nately, current trends seem to indicate that use ofpublic funds to support large-scale stocking is not


acceptable in the existing financial climate, so the prac-tice has declined in several countries (de Silva & FungeSmith 2005). Nevertheless, knowledge of the tech-nique is still available and may well re-emerge as anoption if food security becomes an issue.

In summary, inland fisheries are an importantsource of cash and protein food, particularly inpoorer countries where its products are readily avail-able to the population. Yields at present are probablywell in excess of 10 million tonnes per year, but theprognosis for the future is far from good with manyof the external drivers reducing the amount beingcaught from many wild fisheries. This will almostcertainly result in issues of changing supply and avail-ability to some rural areas which remain dependentupon inland fisheries as a food source.

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