Are the Most Valuable Resources in Dryland Areas Isolated Wetlands?1

BROUWER, Joosta,

a Brouwer Envir. & Agric. Consultancy, Bennekom, The Netherlands; email:

Abstract — In dryland regions wetlands stand out as areas where water and nutrients accumulate, plant and animal production potential is high, and production risk is low. Wetlands are therefore much sought after in dryland regions, by farmers, pastoralists, fishermen, collectors of natural products, and also wildlife. Economic data from reports on some of the 1,000 isolated wetlands in Niger, presented here, demonstrate this importance to people living at the isolated wetlands as well to people living farther away. The importance of the isolated wetlands is even greater in times of drought. At the same time the isolated wetlands are under threat of disappearing because of increasing human pressure, climate change, land use change in their catchments, etc.. Descriptions of selected wetlands in Niger visited in the mid-1990s and again twelve years later show this, too. Integrated participatory management of wetlands in dryland regions must be effectuated as soon as possible, so that these very important natural resources will be used wisely and sustainably, and not used up. The UNCCD should put this high on its list of priorities.

Keywords — Sahel, isolated wetlands, economic value, threatened ecosystems, participatory integrated management

1  Introduction

Water is what makes life possible in the arid and semi-arid regions of the world that the UNCCD is primarily aimed at. In arid and semi-arid regions rainfall is very undependable. Wetlands, on the other hand, are areas where water is concentrated, thus reducing production risk. Nutrients from sediments and livestock manure are concentrated at wetlands as well, thus increasing ecological and agricultural production potential in comparison with the surrounding drylands. Because of this low production risk and high production potential, wetlands in arid and semi-arid regions are much sought after by people as well as animals. Wetlands also facilitate the utilisation of the drylands surrounding them. In short, in dryland areas wetlands are extremely important resources.

Unfortunately wetlands in dryland areas are also under severe threat. These threats include conflicts of interests between different users and user groups, desertification, climate change, demographic change and socio-economic change, as well as lack of (integrated) management.

In this paper I use the wetlands of Niger to illustrate the value of wetlands in the Sahel and other arid and semi-arid regions, and to emphasise the need to use them wisely. In section 2 the various types of wetlands that occur in Niger are discussed. This is followed in section 3 by a description of their use for different purposes, in the wet season, in the dry season, and in different types of years. In section 4 the economic value of isolated wetlands to different user groups is quantified. In section 5 interactions between different types of wetland use, and with surrounding uplands are discussed. Recent trends and present and future threats to these wetlands are reviewed in section 6. In section 7 conclusions are drawn, and policy recommendations made.

Brouwer (2013) is a powerpoint presentation of this contribution, with pictures telling most of the story. Note that while many of the data are not recent, the story they tell remains valid. And, given the security situation in Niger of the past years, collecting new data is problematic.

2  Wetland Types in Niger

2.1  The few large floodplains

The river Niger drains a catchment of 1.5 million km2. It flows over a length of 550 km through SW Niger. The flow at Niamey, the national capital, varies between 0-1800 m3 s-1, with an average of 1030m3 s-1 (MHE-Niger, 1990a). This average flow was only half as large during the 1980’s, due to increased off-take and lower rainfall (MHE-Niger, 1991c). Along the river in Niger there are 63.000 ha of floodplain, i.e. on average an inundation zone 570 m wide on either bank. Approximately 10.800 ha of floodplain have been converted to irrigation area, mostly for growing rice. (MAE-DEP, 1991: 28; MHE-DFPP 1991).

In the east of the country the Komadougou Yobé forms the border with Nigeria. This river used to flow ten months per year, but in the mid 1990’s it only flowed for six months per year. This was due to a prolonged period of lesser rainfall, but also to the construction of dams upstream: in 1991 there were already 18 of them, with a total storage capacity of 2.6 billion m3 (MHE-Niger, 1991a).

Lake Chad consists of two major basins. In its very south-east Niger borders on the northern basin, which receives its water primarily from the Komadougou Yobé and from overflow from the southern basin. Partly as a result of greatly diminished flow in the Komadougou Yobé, the Niger part of Lake Chad was dry from about 1988-1998. The dry period caused very large parts of it to be invaded by Prosopis juliflora shrubs. (MHE-Niger, 1991a; W.C. Mullié pers. obs.)

2.2  The numerous smaller wetlands

In the north of Niger there are a number of oases, with orchards, grape and date production (de Beaufort and Czajkowski, 1986; MHE-Niger, 1991d). Little information is available about these wetlands. Throughout the country there are also a number of dry, ’fossil’ valleys, sometimes kilometres wide, dating from the time that the Sahara and Sahel were much wetter than now, approximately 6-10.000 years ago. In most of these valleys water hasn’t flown for centuries, some still carry water from time to time, while in all these ancient valleys groundwater is often close to the surface. (MHE-Niger, 1990a-e, 1991b-c)

Finally there are a large number of more or less isolated inland wetlands or lakes, called ‘mares’ in French. They are often located in depressions in the old drainage systems. There are more than 1000 in Niger alone, varying in size between 10 and 2000 ha at maximum extent. Some are very temporary, and only hold water a couple of months each year. Others contain water much longer. A number are even permanent, and always, or almost always, have water (MHE-DRE-Niger, 1993). These wetlands are enormously dynamic. Some disappear due to silting up (MHE-Niger, 1992; Piaton and Puech, 1992), but new ones appear as well. One such new wetland is at Dan Doutchi, in a depression that filled up as the drought broke in 1975: it now covers 1800 ha when full (Brouwer and Mullié, 1994b). By far the greatest number of these isolated wetlands is to be found south of 15° N, in approximately the 300-600 mm rainfall zone, between the line Mali-Tahoua-Lake Chad and the borders with Nigeria and Benin.

Outside of Niger, in just two regions of south-eastern Mauritania there are already at least 244 such isolated wetlands (Cooper et al., 2006). In other parts of the Sahel their prevalence is without any doubt similar.

3  The use of isolated wetlands in Niger for various purposes – differences between the wet season and the dry season and from year to year

See Brouwer (2009, on-line) for more detailed information on the use of isolated wetland in Niger at various times of year.

3.1  Cropping

During the rainy season there is little cropping activity or horticultural activity around isolated wetlands in Niger. Only crops like floating rice can cope with rising or permanently high water levels. During the rainy season, farmers with access to both wetland frontage and upland fields will be working on their upland fields, where they grow their staple food, pearl millet.

In agricultural statistics in Niger a distinction is seldom made between dry-season cropping that is irrigated, and dry-season cropping that is dependent on residual moisture in the soil. In the latter, as the water in wetlands recedes, crops are sown in the emerging soil. As the water stored in the soil is used up by the crop, supplementary irrigation is sometimes applied. Dry season cropping concerns crops like onions, tomatoes, beans, sweet potato, cabbage, lettuce and peppers (pers. obs.). These crops have a much higher nutritional value than the staple millet. Much of the dry season cropping is for (international) commercial purposes.

There is inter-annual variation in the area used in Niger for dry season cropping. During the years 1984-1991 it varied between 42.000 ha and 64.000 ha, rice not included (MAE-Niger, 1993). Dry season cropping was most extensive during 1984 and 1989: 63-64.000 ha, vs. <54.000 ha in other years. These two years were respectively a drought year and a year with patchy rainfall and poor millet harvests in many parts of the country. This shows that the total area useable for e.g. recession agriculture cannot be reduced with impunity: areas not used during good rainfall years may be an essential safety net during years of poor rainfall (Brouwer and Ouattara, 1995).

3.2  Livestock rearing

During the rainy season wetlands can provide drinking water to livestock, although the availability in the uplands of green feed and surface pools makes that less necessary. In some wetlands, but mostly along the Niger river, the grass ‘bourgou’, Echinochloa stagnina, may be grown during the wet season on rising water levels. When the water level has dropped it is harvested for hay.

During the dry season isolated wetlands can provide drinking water for livestock, and also grazing. Herders can bring in local cattle and small ruminants to drink every day, or every few days. Transhumance herders only use a particular wetland during a limited time of the year, as a part of their annual treks that sometimes cover thousands of kilometres.

No data could be found on inter-annual differences in utilisation of isolated wetlands by livestock. With livestock numbers decreasing during drought periods, utilisation by livestock of wetlands for drinking will also be lower during droughts. It should be noted that a particular isolated wetland may be important for livestock only once very so many years, when it can, and the other wetlands cannot, provide what the livestock and herders need. But if that year that wetland is not available because it has been used for other purposes, the whole associated livestock rearing system may collapse.

3.3  Fishing

During the rainy season fishing activity is generally low. Measures to increase fish production, such as re-stocking and increasing aquatic vegetation for fish to spawn in, do take place during the rainy season (MHE-DFPP, 1991).

Fishing mostly takes place during the dry season, when fish stocks have had time to grow and/or are driven closer together as the water level recedes. The main species caught are Clarias gariepinus (catfish), Tilapia nilotica, T. zilii and Lates niloticus (Nile perch). Also Bagrus bayad, Protopterus annectens (lungfish) and Auchenoglanis sp. (Brouwer and Mullié, 1994a).

Inter-annual variation in rainfall will lead to inter-annual variation in the maximum water level in isolated wetlands, and thus to variability in fish production in those wetlands. A nation-wide drought in 1984 did indeed lead to low fish production the following year, as mentioned in section 4.3. During drought years more aestivating lungfish Protopterus annectens may be dug out of the mud of dried out wetlands to serve as hunger food (Raverdeau, 1991; Cheferou Mahatan,1994; Brouwer and Mullié, 1994a).

3.4  Hunting and tourism

Hunting was largely banned in Niger in 1974, other than by traditional means. In 1996 hunting was legalised again on a much larger scale (Brouwer et al., 2001). The rainy season is not the preferred season for hunting, except for the collecting of eggs of e.g. Comb Duck Sarkidiornis melanotos. These eggs may be put under chickens and the hatched ducklings raised for later consumption (pers. obs.). For tourism, too, the rainy season is not the preferred season. Although the landscape is beautifully green at that time of year, travel to isolated wetlands along unsealed roads can be quite difficult. There are also many more mosquitoes than during the dry season.

The dry season is when most hunting in Niger takes place. Even before 1996 it was not uncommon for ducks and geese to be hunted with shotguns, at least along the Niger river. Live decoys and baited lines have been used as well (Giraudoux et al., 1988; Mullié et al., 1996). We have also seen little boys use catapults, as well as glue-sticks, to catch birds coming in to drink (Brouwer and Mullié, 1994a). Birds may also be caught as by-catch on fishing lines with hooks. In the local markets a multitude of animal species, including species found at isolated wetlands, are for sale for medicinal and magical purposes. To what extent these animals are caught in Niger itself is not clear (Brouwer and Mullié, 1994a).

There are no data about differences between years, as there is as yet little or no hunting or tourism at isolated wetlands in Niger,. Note that hunters often do not live at the wetlands they hunt at. If the local population does not profit from the hunters, the hunters may not be welcome. The same goes for tourists, of course.

3.5  Collecting of natural products

Local people collect natural products from their wetland during the whole year. These include wood for cooking; wood for construction (trees around wetlands are often larger than those growing further away from water); clay for brick making and pottery; water for domestic purposes, including the washing of clothes; plant (and animal?) products for traditional medicinal and magical purposes (Brouwer and Mullié, 1994a).

Products collected primarily during the dry season include the fruits and tubers of water lilies Nymphaea sp. for human consumption; bourgou Echinochloa stagnina to feed livestock; and water for agricultural purposes (Brouwer and Mullié, 1994a). Collectors may be local but may also come from further away.

3.6  Biodiversity

The vegetation of isolated wetlands in Niger, if present, often shows a concentric pattern, in which the dominating species varies with the depth and duration of inundation. Closest to the shore there is generally a zone dominated by the grass species Veteveria nigritana (shortest inundation time); then follow Oryza longistaminata (wild rice), Echinochloa stagnina (bourgou), and finally Nymphaea lotus and N. caerulaea (waterlilies, where there is water a meter or more deep at least four to five months of the year). In addition to these herbaceous species there may or may not be trees, sometimes in dense stands. These include various Acacia species, and Mitragyna inermis. (Mullié et al., 1999)

During the rainy season most mammals as well as most birds are not very dependent on isolated wetlands, as there will be sufficient surface pools for drinking throughout the landscape. The wetlands in the Liptako Gourma region north-west of Niamey harbour an important population of Black-crowned Cranes Balearica pavonina, a Sahelian species that is threatened .throughout its range by disappearance of wetlands, disturbance and capture for the live bird trade (Meine and Archibald, 1996; Brouwer and Mullié, 2001).

During the dry season large mammals such as antelopes, buffalo, elephants, hyenas, jackals, foxes, and even lions used to come to drink at isolated wetlands in Niger. However, other than foxes there are very few large mammals left in Niger, outside ’W’ National in the south-west of the country. Waterbird counts were conducted every year during January-February during 1992-1997, along the Niger River as well as at isolated wetlands throughout the country. In total more than 100 species of waterbird were observed during those counts, and almost 40 species of raptor. During the dry season Niger is host to an estimated 1.8 million waterbirds on average. Most of these have been born in Europe or Asia, and some fly more than five thousand kilometres to spend the Eurasian winter in Niger. Niger’s wetlands are therefore also important to the conservation of Europe’s and Asia’s biodiversity. (Mullié and Brouwer, 1994a, 1994b; Mullié et al., 1999; Brouwer and Mullié, 2001)

There is clear inter-annual variation in the importance of isolated wetlands in Niger for waterbirds. Two thirds of the waterbirds in Niger, on average about 1.2 million, use the isolated wetlands, depending on how much rain has fallen the preceding rainy season. The Niger River becomes more important when the rains have been poor and the isolated wetlands only partly filled.

4  Economic values of isolated wetlands

See Brouwer (2009, on-line) for more detailed information on the economic values of isolated wetland in Niger

4.1  Dry season cropping

In the 1990’s, financial returns per hectare per year in dry season cropping varied from 60.000 (low input Dolichos lablab) to 1.300.000 (onions) F CFA, or from $ 200 to $ 4.300 per ha per year (Raverdeau, 1991; Cheferou Mahatan, 1994). An upland millet crop would average $ 70 per ha per year (Brouwer and Mullié, 1994a). Around Illela, Niger, women each worked about 200 m2 of land during the dry season, while men worked about 2000 m2 (Cheferou Mahatan, 1994). Some people worked their own land, others rented it at up to $ 200 per ha per year. Introduction of motor pumps meant less people were needed to work the same area of land (Andreas Mueller, Projet Marécage Illela, pers. comm. 1994).

It is worth noting that irrigation projects may provide food and shelter to bird pests, particularly during the dry season when normally they would perish (Morel, 1971; Mullié, 1994). And irrigation projects, too, have a finite life: for irrigated areas in SE Australia the period of useability is estimated at 150-200 years (Meyers, 1994).

4.2  Livestock raising

Estimated livestock numbers, trade and production prices in Niger, from 1980 to 1991, are given in MAE-Niger (1993: 95-105). Cattle fetched about $ 130-200 per head in 1990, bulls $ 230-300, rams $ 26-43, goats $ 13-20. As an example of economic turnover, in the Region of Tahoua the exploitation rate (trade and slaughter) of cattle, sheep and goats in 1990 was given as 5.1, 9.9 and 6.9% respectively (MAE-DEP, 1991). Livestock clearly form a very important part of economic activity in Niger. If it is assumed that one-third of livestock production in Niger is dependent on isolated wetlands for its water supply, then the value of wetlands to livestock production in Niger was around $ 35 million per year in the early 1990’s (Brouwer, 2009).

4.3  Fishing

In 1989, the fish catch in the Region of Tahoua alone, one of the seven rural Regions of Niger, was estimated at 430 tons, with a value of more than $ 250.000 at the wetlands where they were caught (MHE-DFPP, 1991). In the capital Niamey the value of the fish was 5-10 times higher (pers. obs.). In 1993 it was estimated that, with an investment of $ 1 million, the fish production in the Region of Tahoua could be increased to 1.500 tons per year, with an annual value of close to $ 1 million at the then current prices. A total production of 2000 tons per year was considered achievable. (MHE-DFPP, 1991). Data for all of Niger are given in Figure 1 as well. Before 1975 fishermen at isolated wetlands in the Region of Tahoua were almost all from Nigeria (MHE-DFPP, 1991). At times this led to conflicts about access rights to wetlands (MHE-DFPP, pers. comm. 1994).

4.4  Hunting and tourism, collecting of natural products and biodiversity

As there is as yet little or no hunting or tourism at isolated wetlands in Niger, its potential is completely undeveloped. On the value of collecting of natural products, and of biodiversity, no data could be found. What value would conservationists in Europe attach to for instance the millions of waterbirds from Europe that spend the northern winter at isolated wetlands in the Sahel?

4.5  Summary of economic data

Table 1 summarises the estimates of the very considerable annual values that isolated wetlands in Niger had for different uses in the early 1990’s. Since then the population of Niger has doubled, from 6 to 12 million. Utilisation by the local population of especially isolated wetlands has increased accordingly. Over those twenty years, the prices that are being paid for products from the wetlands have increased enormously as well. In short, isolated wetlands in Niger are generally even more, much more, important than they were twenty years ago. Except of course those wetlands that have already become seriously degraded, reducing their production value.

Table 1: Some estimated economic values of isolated wetlands in Niger in the early 1990’s. See Brouwer (2009), on-line.
Product SeasonYearExtent and valueRemarks
Croppingrainy ?Value probably quite low; cropping priority is uplands
Croppingdry199142-64.000 ha per yr $200-$4300 per haarea greater following poor rainy season in uplands; high nutrition, high value crops
Livestock keepingrainy & dry1991$35 million per yearvalue of traded livestock that was dependent on wetlands for water
Fisheriesrainy & dry1978-19851.100-5.000 tons per yearfish catch at all isolated wetlands, in Niger, value to fishermen
Fisheriesrainy & dry1978-1985$5-20(-40) million per yearfish catch at all isolated wetlands in Niger, city prices
Fisheriesrainy & dry1989430 ton, $250.000 per yearRegion of Tahoua only; value in Niamey 5-10x greater; potential 2.000 ton
Hunting & tourismdry ?potential completely undeveloped
Collecting of natural productsrainy & dry ?water, wood, clay; plant & animal products
Collecting of natural productsdrydrought years?waterlily fruits and tubers, and lungfish, are emergency food in times of drought
Biodiversityrainy ?almost no information
Biodiversitydry ?average 1.2 million waterbirds in Jan-Feb; other species?

For some users, such as pastoralists, isolated wetlands are essential to their way of life. For other groups, having access to wetlands as well as drylands increases the range of crop and livestock production options, from which they can choose depending on how good the local rains and the flood levels of the wetland are or were. As many authors have reported, risk reduction is a major goal for resource-poor farmers in the Sahel (e.g. Ubels and Horst, 1993: 29; Brouwer and Mullié, 1994a).

5   Interactions between wetlands and uplands and between different types of wetland use

Values of isolated wetlands for a particular purpose also depend on interactions with utilisation for other purposes. Sometimes such interactions are competitive and negative, sometimes they are positive. They can be local and intermittent, but also long-distance and permanent. For a full evaluation of links between isolated wetlands in the Sahel and associated uplands, and interactions between different user groups see Brouwer (2009), available on-line. The following points are a summary of what is written there.

Interactions between wetlands and uplands

  • Uplands can provide water and nutrient-rich sediments to wetlands, but too much water and/or too much sediment is detrimental
  • Too many dams and too much water off-take upstream will cause downstream wetlands to deteriorate or even die.
  • Raising the outflow level at a particular wetland will effect the water regime and the vegetation at the wetland and downstream.
  • Activities around wetlands can provide extra income that can be invested in uplands, and vice versa; but there can also be competition for resources, including labour.
  • Isolated wetlands are linked to local grazing areas by local livestock, and to more distant grazing areas and wetlands by transhumance livestock. The wetlands and grazing areas further south help make it possible to exploit the rainy-season livestock production potential of the northern Sahel. Without dry-season watering and grazing in the south, there can be no grazing in the north.

Cropping effects on other uses

  • Fish can spawn among the residues of the crops of the preceding dry season.
  • Increased dry season cropping would make an isolated wetland less attractive for livestock raising, hunting, tourism, collecting of natural products, biodiversity, and possibly fishing. In providing additional dry season employment opportunities, dry season cropping may also lead to a reduction in seasonal outmigration in search of work.

Livestock raising effects on other uses

  • Browsing, grazing and trampling by livestock can destroy the wetland vegetation, leading to a reduction of habitat for waterbirds and other animals, and also to a disappearance of resources for people..
  • Fishing and biodiversity can profit from livestock rearing because of the transfer of nutrients by livestock to isolated wetlands. The livestock watered at isolated wetlands in Niger have been estimated to contribute up to 10 tons of manure and associated urine per hectare per year, containing 300 kg N, 30 kg P and the associated energy of the organic matter for use by detritus-eating organisms (unpubl. data). This has an enormous effect on plant and animal production at the wetlands, including fish production and waterbird presence (see Brouwer, 2009). These latter uses will suffer if livestock raising is crowded out or disappears for other reasons.
  • It is not clear to what extent dry season cropping around isolated wetlands also profits from the transfer of nutrients by livestock to those wetlands. It would be very interesting to investigate that, given the conflicts between farmers and pastoralists at wetlands, with pastoralists often having to give way to farmers and give up access to wetlands and grazing resources.

Fishing effects on other uses

  • Isolated wetlands may be linked to other areas through fishermen that come from elsewhere to fish at the wetland.

Collecting of natural products effects on other uses

  • Harvesting of aquatic and fringing vegetation at wetlands, trees as well as herbs, by locals and by people from upland areas, is too often unsustainable and destructive, leading to a reduction of habitat for waterbirds and other animals, and also to the disappearing of resources for people.

Biodiversity and Hunting and tourism effects on other uses

  • Biodiversity at isolated wetlands is obviously important to collectors of natural plant and animal products.
  • The introduction, accidental or otherwise, of plants such as Water Lettuce Pistia stratiotes, Water Hyacinth Eichhornia crassipes, and bulrush Typha sp., may affect the collection of natural products.
  • Biodiversity is likely to be negatively affected, immediately or eventually, by increases in dry season cropping; degradation or destruction of aquatic and fringing vegetation by farmers, fishermen, herders and/or livestock; by an increase in disturbance by the same groups; by changes in the flooding regime through the raising of the outflow level of the wetland and/or increased retention of water upstream in the catchment; by too much hunting or hunting at too many wetlands; and by overcollection of natural products.
  • Waterbirds at a particular wetland link that wetland with the other wetlands they frequent. These include wetlands in the same area with which the wetland forms a habitat system for all or part of the year; as well as all the other wetlands along the flyways of the birds concerned. Bird ringing and satellite tracking studies have shown that migratory birds link Niger to at least 93 other countries, from Guinea to NE Canada, across Scandinavia to Siberia, and down via the Caucasus and the Middle East to Madagascar and South Africa.

6  Recent trends and threats to isolated wetlands in the Sahel

A number of recent trends at, and changes to, isolated wetlands in the Sahel have already been mentioned in the previous section. Many of them are part of, or related to, world-wide demographic, climatic, environmental and socio-economic changes. The casual observer will say that whether these trends are seen as opportunities or threats will depend on one’s point of view. However, that is not completely correct. For not overly large wetlands near Zinder, southern Niger, Framine (1994) already estimated that, without proper counter measures, it would take only 10-20 more years for a change from an aquatic to a marshy ecosystem to be effected. At the same time it was said that 20-30 years after farmers move in, wetlands will be degraded for all kinds of use, including cropping. This degradation is confirmed by data in Table 2, where a comparison is made between the situation at a dozen isolated wetlands in southern Niger in 1992-1997 and in 2006-2008. In my considered opinion much of this degradation at isolated wetlands in Niger is due to a lack of PINReM, Participatory Integrated Natural Resource Management.

Table 2: Examples of changes happening at isolated wetlands in Niger, from 1992-1997 to 2006-2008 (based on Brouwer 2010, available on-line). IBA = Important Bird Area according to BirdLife International (Fishpool and Evans, 2001).


Examples of changes
Kobadié wetland, 50 km SW of Niamey along the road to Ouagadougou, ca. 20 ha: 1992-1997: wonderful looking wetland with lots of trees and full of waterlilies, many birds; used by local people was very moderate
2006: all large trees (Khaya senegalensis) and most medium size trees (Mitragyna inermis) were cut; many more people were present, lots of disturbance, and few birds.
IBA Kokoro wetland, 30 km NE of Téra and 150 km NW of Niamey, max. 2,100 ha 1992-1997: up to 13.108 waterbirds of 44 species in a glorious setting of flooded grassland surrounded by patches of Acacia nilotica forest, red dunes, huge granite boulders and palm trees
2008: large areas of fringing Acacia nilotica forest had been cleared; a lot more vegetable gardens had been constructed; and grazing pressure by livestock on the aquatic vegetation had increased enormously (perhaps in part because of the poor rains the preceding year, but most likely because of an increase in population and livestock size); waterbirds were concentrated in a much smaller area of the original wetland and were much less in number (approx. 7.200).
IBA Namga or Namaga wetland, and 40 km NE of Téra and 150 km NW of Niamey, max. 500 ha 1992-1997: up to 13,190 waterbirds of 54 species;
2008: the wetland had mostly dried up due to poor rains in 2007; the adjoining village, from which the wetland received its name, had grown significantly; only about 1.200 waterbirds were observed.
Mari wetland,10 km NE of Tillabéri, 100 km NNW of Niamey, max. 270 ha 1992-1997: up to 4,266 waterbirds;
2006: no waterbirds present because an earthen dam had been constructed to raise the level of the outflow of the wetland, while the (former?) wetland had been almost completely taken over by farmers.
Yaya wetland, 40 km W of Birni N’Konni 1992-1997: a total of 122 waterbirds was counted in this nice little wetland, next to a village;
2006: although still quite nice and with some waterbirds, now there was a clear increase in population and human activity when compared to the situation ten years earlier.
IBA Dan Doutchi wetland, 80 km NW of Birni N’Konni, max. 1800 ha; originated in 1975 after a huge rainfall event which followed the drought of 1973-1974 1992-1997:up to 55 species of waterbird;
2006: an earthen dam had been built to raise the level of the outflow of the wetland; still a lot of water present, with people, fishing activities and vegetable growing and some other human influence; very few waterbirds still present in the area.
IBA Tchérassa reservoir, 6 km NE of Birni N’Konni 1992-1997: 15,000 Cattle Egrets and 3,000 other waterbirds (mostly ducks) present in January 1994;
2006: large areas of Acacia nilotica had been cut, especially in the areas where the Cattle Egrets used to roost; an increase in human population and activity was obvious.
Galmi reservoir, 60 km E of Birni N’Konni 1992-1999: up to 1,033 of waterbirds;
2006: few waterbird present, while the population pressure and fishing activities appeared to have increased
Tabalak wetland, 25 km NE of Tahoua along the road to Agadez, max. 1,150 ha 1992-1997: up to 5,464 waterfowl of 48 species; Tabalak used to have quite a few trees along its northern end (Acacia nilotica, A.albida, Prosopis juliflora, and Balanites aegyptiaca), but in 1993 many of these were cut; in 1993-1994, about 20% of the perimeter was covered by vegetable gardens, while 80% was accessed by livestock;
2007: many less waterbirds, in combination with a big increase in human population and human activities; it appeared that 80% of the perimeter was now covered by vegetable gardens (with some narrow passages for livestock that want to reach the water), and only 20% was freely accessible to livestock.
Liptako-Gourma region, where the countries of Niger, Burkina Faso and Mali meet. The Liptako-Gourma is an area with (still) lots of great wetlands, threatened by population increases, migration and climate change. Some of the wetlands are probably also threatened by the construction of a dam in the Niger River at Kandadji, south of Ayorou, about 80 km south of the Niger-Mali border. Dam construction implies employment and (temporary) settlement of laborers; this condition attracts people that provide goods and services to these laborers, causing, e.g.: construction of housing, for which timber is cut; in dry areas much of the timber grows in drainage lines and around wetlands; provision of firewood, for which wood is cut; growing of vegetables, mostly around wetlands, which means less access to those wetlands for pastoralists and destruction of the bordering vegetation.

Because of the continuing urbanisation, the demand for rice in Niger, and elsewhere in West Africa, will continue to increase. There have been proposals to develop a further 70.000 ha of land for irrigation in Niger, out of 210.000 ha considered suitable, much of it around isolated wetlands. The market for various other crops grown around wetlands will no doubt increase as well. In addition there is the increasing pressure due to population growth, which in Niger is estimated at 3.1% per annum or more. That growth percentage means a doubling of the population in less than 23 years, and a quadrupling in 45 years. Around wetlands the pressure will grow even faster, due to migration to wetlands from upland areas.

What effects climate change will have on all this is uncertain, but no-one appears willing to bet that the effects of climate change will be positive in the Sahel. This in spite of the fact that the drought of 1973-74 has led to the creation of quite sizeable (up to 1800 ha), new isolated wetlands in Niger.

All in all, there is no doubt that the human pressure on wetlands in Niger will increase enormously during the years to come. It remains to be seen how the poorest people will fare under such conditions if they are not offered help. Under present conditions, in particular poor people still have a lot of (traditional) access to wetlands and their resources. The danger is that those traditional access rights will be diminished by new developments. Transhumance pastoralists, present at isolated wetlands only part of the year, are likely to lose out to farmers, present all year round. At the same time conversion of upland grazing areas to millet fields has forced pastoralists to try their luck further north, where as yet there is less pressure from agriculture. This has caused for instance Peuhl to graze their herds in formerly Touareg areas, again leading to conflicts. Fishermen, collectors of natural products and biodiversity are also likely to be affected.

What then is the best way to further manage and develop Sahelian wetlands? Unfortunately, there is no simple answer. What is important is that it is realised how things came to be as they are, and what side effects proposed changes may have. Certainly, without creation and/or maintenance of the right infrastructure and macro-economic climate, wetland management and development will come to nought (cf. Breman, 1992). What is also clear is that management and planning will have to be participatory to be successful (cf. Dugan, 1990; Ubels and Horst, 1993; Kouokam, 1994). In addition, appropriate attention will have to be paid to traditional techniques for utilising the wetlands; to possible tradeoffs between the various types of wetland utilisation for production and conservation; and to the different roles of men and women in the traditional production processes, with women often working smaller areas and growing different crops (Ubels and Horst, 1993; Cheferou Mahatan, 1994). Finally, management and development of Sahelian wetlands will without doubt have to take account of the intimate relationships that exist between the use of wetlands; the use of the drylands that surround them; and the use of other areas further away and at other times of year by people and animals that use the isolated wetlands in the Sahel only during particular seasons.

I would like to add that the importance of isolated wetlands to many user groups is not just limited to the Sahel. Scoones (1991) gives a similar but more wide-ranging evaluation of the importance of small wetlands in semi-arid areas of Africa. Other relevant publications include Dugan (1990), Claude et al. (1991), Hollis et al. (1993), and Sally et al. (1994).

7  Conclusions and policy oriented recommendations

From the above it will be clear that isolated wetlands in the Sahel, and arguably in other arid and semi-arid regions of the world, are

  • natural resources that are very valuable to a quite a number of user groups,
  • under severe threat from a number of processes that include desertification,
  • poorly known.

There is no recent synthesis of what is known about these isolated wetlands, and not even a good inventory of what wetlands there are, how they are utilised, what their value is, and how they might best be managed.

What the UNCCD should do with urgency for isolated wetlands in the Sahel, and probably in other arid and semi-arid regions of the world, together with the Ramsar Bureau, national Ramsar Committees, and other national and international bodies, is:

  1. make an inventory of, and database with, all wetlands larger than e.g. 10 ha when they are full (or perhaps >50 ha to start with)
  2. add to that database information on the physical characteristics of each wetland, its utilisation by people, its biodiversity, its economic value, and the threats to its functioning
  3. encourage the formulation and implementation of National Wetland Programmes that will in due course take over the coordination of the first two tasks, and that will promote and help implement wise use of all wetlands, through Participatory Integrated Natural Resource Management based on the Ecosystem Approach of the Convention on Biological Diversity.


Breman, H. (1992): Desertification control, the West African case; prevention is better than cure. Biotropica, 24(2b): 328-334.

Brouwer, J. (2009): The seasonal role of isolated wetlands in the Sahel: key resources for people and biodiversity, under pressure from global change. Paper presented at ’Seasonality Revisited’, an International Conference organised by the Future Agricultures consortium at the Institute of Development Studies, Brighton, UK, 8–10 July, 2009. (1 July 2013)

Brouwer, J. (2010): Climate Change in Dryland and Wetland Ecosystems in the Sahel Region. In: Andrade Pérez, A., Herrera Fernandez, B., Cazzolla Gatti, R. (eds.), Building Resilience to Climate Change: Ecosystem-based adaptation and lessons from the field, 32-45, Gland: IUCN. ?6297/Building-resilience-to-climate-change–ecosystem-based-adaptation-and-lessons-from-the-field (1 July 2013)

Brouwer, J. (2013): Are the most valuable resources in dryland areas isolated wetlands? Paper presented at the Second Scientific Conference of the UN Convention on Combatting Desertification, Bonn, Germany, 9-12 April 2013. (1 July 2013)

Brouwer, J. and Mullié, W.C (1994a): Potentialités pour l’agriculture, l’élevage, la pêche, la collecte des produits naturels et la chasse dans les zones humides du Niger, in : Kristensen, P. (ed.), Atelier sur les zones humides du Niger. Proceedings of a workshop, 2-5 November 1994, La Tapoa/Parc du W, Niger, 27-51, Niamey, Niger: IUCN-Niger.

Brouwer, J. and Mullié, W.C. (1994b): The importance of small wetlands in the central Sahel. IUCN Wetlands Programme Newsletter, 9: 12-13.

Brouwer, J. and Mullié, W.C. (2001): A method for making whole country waterbird population estimates, applied to annual waterbird census data from Niger. Ostrich, Supplement No. 15: 73-82.

Brouwer, J. and Ouattara, M. (1995): Interactions between wetlands and surrounding drylands in the Sahel: a key to sustainable use. Paper presented at the meeting of IUCN’s SAWEG (Sahelian Wetlands Expert Group), Dakar, Senegal, 21-24 May 1995.

Brouwer, J., Codjo, S.F. and Mullié, W.C. (2001): Niger, in: Fishpool, L.C.D., Evans M.E. (eds), Important Bird Areas of Africa and Associated Islands: Priority Sites for Conservation., BirdLife International Conservation Series no. 10, 661-672, Cambridge and Newbury, UK: BirdLife International and Pisces..

Cheferou Mahatan (1994): Etude de la filière des cultures de contre-saison, zone du PMI. SNV-Netherlands Organisation for Development Aid, Projet Mares Illela, Niamey, Niger.

Claude, J., Grouzis, M. and Milleville, P. (1991) : Un espace sahélien: la mare d’Oursi, Burkina Faso, Paris : Editions ORSTOM..

Cooper, A., Shine, T., McCanna, T. and Tidane, D.A. (2006). An ecological basis for sustainable land use of Eastern Mauritanian wetlands. J. Arid Envir., 67: 116–141.

de Beaufort, F., and Czajkowski, A.-M. (1986). Zones humides d’Afrique septentrionale, Centrale et Occidentale. II Inventaire préliminaire et méthodologie. Inventaires de Faune et de Flore, Fascicule 35, Paris: Conseil International de la Chasse et de la Conservation du Gibier, Sécretariat de la Faune et de la Flore, Muséum National d’Histoire Naturel.

Dugan, P.J. (ed.) (1990): Conservation de zones humides, Gland: IUCN.

Fishpool, L.C.D., Evans, M.E. (eds) (2001): Important Bird Areas of Africa and Associated Islands: Priority Sites for Conservation, BirdLife International Conservation Series no. 10, Cambridge and Newbury, UK: BirdLife International and Pisces.. 1144 pp

Framine, N. (1994): Pisciculture des zones humides: compatabilité, exploitation et conservation, in: Kristensen, P. (ed.), Atelier sur les zones humides du Niger. Proceedings of a workshop, 2-5 November 1994, La Tapoa/Parc du W, Niger, 17-26, Niamey, Niger: IUCN-Niger.

Giraudoux, P., Degauquier, R., Jones, P.J., Weigel, J. and Isenmann, P. (1988). Avifaune du Niger: état des connaissances en 1986. Malimbus, 10: 1–140.

Hollis, G.E., Adams, W.M. and Aminu-Kano, M. (eds) (1993): The Hadejia-Nguru Wetlands. Environment, economy and sustainable development of a Sahelian floodplain wetland. Gland and Cambridge: IUCN.

Kouokam, R. (1994): Application de la méthode accélérée de recherche participative "MARP" dans la zone pilote du Projet Waza-Logone (Province de l’Extrême-Nord du Cameroun. Paper prepared for the IUCN Workshop on the Initiative on Sahelian Floodplains, Tapoa, Niger, 31 October - 2 November 1994.

MAE-DEP (1991): Annuaire Statistique Séries Longues, 1991. Niamey, Niger: Ministère de l’Agriculture et de l’Elevage, Direction des Etudes et de la Programmation.

MAE-Niger (1993): Annuaire des statistiques de l’agriculture et de l’élevage 1991. Niamey. Niger: Ministère de l’Agriculture et de l’Elevage, Directions des Etudes et de la Programmation, Service d’Analyse des Politiques et de la Coordination des Statistiques. 111 pp. + figures.

Meine, C.D. and Archibald, G.W. (eds.) (1996): The Cranes: - Status Survey and Conservation Action Plan. Gland: IUCN.

Meyers, W.S. (1994): Australian irrigation: balancing rights and responsibilities, production and conservation. Soils News (Newsletter of the Australian Society of Soil Science), 99, July 1994: 1-4.

MHE-DFPP (1991): Organisation de la production et de la commercialisation du poisson dans le Département de Tahoua. Rapport de Projet. Niamey, Niger: Ministère de l’Hydraulique et de l’Environnement, Direction de la Faune, de la Pêche et de la Pisciculture.

MHE-DRE-Niger (1993): Liste des mares et leur régime. Niamey, Niger: Min. de l’Hydraulique et de l’Envir., Direction des Ressources en Eau.

MHE-Niger (1990a-c): Synthèse des ressources en eau du Département de Tillabéri./Zinder/Tahoua Projet PNUD/DCTD NER/86/001. Niamey, Niger: Ministère de l’Hydraulique et de l’Environnment, Direction Départementale de l’Hydraulique de Tillabéri.

MHE-Niger (1990d-e): Les nappes aquifères à l’Ouest de l’Aïr – synthèse hydrogéologique. Première partie: les nappes paléozoiques. Deuxième partie: les nappes des gres d’Agadez. Projet PNUD/DCTD NER/86/001. Niamey, Niger: Ministère de l’Hydraulique et de l’Environnement, Direction des Ressources en Eau.

MHE-Niger (1991a-d):. Les ressources en eau du Département de Diffa/Maradi/Dosso/ Nord-Est Nigérien. Projet PNUD/DCTD NER/86/001. Niamey, Niger: Ministère de l’Hydraulique et de l’Environnment. Direction Départementale de l’Hydraulique de Diffa.

MHE-Niger (1992): Séminaire National sur l’Etat de Connaissance de Ressources en Eau du Niger. Contribution des Directions Départementales de l’Hydraulique et du Genie Rural de Maradi. Maradi, du 21 au 25 avril 1992. Maradi, Niger: Ministére de l’Hydraulique et de l’Environnement, Direction Départementale de l’Hydraulique de Maradi.

Morel, G.J. (1971): Report on the controversy between agriculture and waterfowl conservation in West Africa. Report to the 17th Annual Executive Board Meeting of the International Wildfowl Research Bureau, Slimbridge, Glos., England, 9-10 Dec. 1971.

Mullié, W.C. (1994): [Capture and trade of the Red-billed Quelea Quelea quelea in the Lake Chad Basin: sustainable use of a biological resource.], Niamey, Niger: DFPV (in French).

Mullié, W.C. and Brouwer, J. (1994a): with Dupont, P., Codjo, F., Adamou Kounou and Souvairan., P., Waterbirds and wetlands in the Sahel: a threatened resource. Results of three years monitoring (1992-1994) in the Republic of Niger. Report submitted to IUCN-Niger.

Mullié, W.C. and Brouwer, J. (1994b): L’importance des zones humides au Niger pour les oiseaux d’eau afrotropicals et paléarctiques, in:. Kristensen, P. (ed.), Atelier sur les zones humides du Niger. Proceedings of a workshop, 2-5 November 1994, La Tapoa/Parc du W, Niger, 57-74, Niamey, Niger: IUCN-Niger.

Mullié, W.C., Brouwer, J. and Scholte, P. (1996): Numbers, distribution and habitat of wintering White Storks in the east-central Sahel in relation to rainfall, food and anthropogenic influences, in:.Biber, O., Enggist, P., Marti, C., Salathé, T. (eds.), Proceedings of the International Symposium on the White Stork (Western Population), Basel, Switzerland, 7-10 April 1994, 219-240.

Mullié, W.C., Brouwer, J., Codjo, S.F. and Decae, R. (1999): Small isolated wetlands in the Sahel: a resource shared between people and birds, in: Beintema, A., van Vessem, J. (eds), Strategies for conserving migratory waterbirds - Proceedings of Workshop 2 of the 2nd International Conference on Wetlands and Development held in Dakar, Senegal, 8-14 November 1998., Wetlands International Publication 55, 30-38, Ede, Netherlands: Wetlands International.

Piaton, H. and Puech, C. (1992): avec Carette, J.: Apport de la télédétection pour l’évaluation des ressources en eau d’irrigation pour la mise en valeur des plans d’eau à caractère permanent ou sémi-permanent au Niger. Rapport de synthèse, Ouagadougou, Burkina Faso and Lausanne: Comité Interafricain d’Etudes Hydrauliques and Ecole Polytechnique Fédérale de Lausanne.

Raverdeau, F. (1991): La contre saison au Niger. Etude des systèmes de culture dans les départements de Tillabery et Dosso, Niamey, Niger: Université de Niamey, Faculté d’Agronomie.

Sally, L., Kouda, M. and Beaumond, N. (eds) (1994): Zones humides du Burkina Faso. Compte rendu d’un séminaire sur les zones humides du Burkina Faso, Gland: IUCN Wetlands Programme.

Scoones, I. (ed.) (1991): Wetlands in drylands: the agroecology of savanna systems in Africa. Part 1: Overview - ecological, economic and social issues, London: International Institute for Environment and Development.

Ubels, J. and Horst, L. (eds) (1993): Irrigation design in Africa. Towards an interactive method. Wageningen and Ede, The Netherlands Wageningen Agricultural University and Technical Centre for Rural and Agricultural Co-operation.


Brouwer, J. (2014): Are the Most Valuable Resources in Dryland Areas Isolated Wetlands? In: Planet@Risk, 2(1), Special Issue on Desertification: 47-56, Davos: Global Risk Forum GRF Davos.

This article is based on a presentation given during the UNCCD 2nd Scientific Conference on "Economic assessment of desertification, sustainable land management and resilience of arid, semi-arid and dry sub-humid areas", held 9-12 April 2013 in Bonn, Germany (