Niger Delta Ecosystems: the ERA Handbook/The Resources of the Niger Delta
11 THE RESOURCES OF THE NIGER DELTA
- Renewable and Non-Renewable Resources
- Land
- Water
- Fish
11.1 RENEWABLE AND NON-RENEWABLE RESOURCES
The resources of the Niger Delta are all those things that people want to take in order to survive and/or in order to make money. They are described as being Renewable or Non-Renewable.
Renewable Resources
Renewable resources are the products of non-geological, short-term resource cycles as described in the previous chapter, such as fish, fertile soil and timber. They are renewable because they are continually available if the ecosystems that produce them remain viable, and because they can be reproduced by mankind (for instance trees can be planted for timber).
Non-Renewable
Non-renewable resources are the products of much longer resource cycles. In other words, in any time less than geological time, they can be used once only. Examples are salt and oil. A number of resources, while not being strictly renewable, are reusable. For instance rocks can be used for buildings again and again. Also modern human technology has extended the "renewability" of non-renewable resources. For instance, sump-oil can be refined, and waste paper can be pulped in order to make new paper.
Contrary to the popular view, most renewable resources are less easy to manage than non-renewable resources. This is because renewable resources are only potentially renewable and are dependant upon healthy ecosystems: Modern Society seems unwilling (because of short-term economic laws) or unable (because of ignorance) to manage ecosystems in a way that ensures the sustainable production of resources. This is a worldwide problem, so that, for instance, fish stocks in Europe's North Sea are declining just as fast as are the fish stocks in the Bight of Guinea because of bad management.
On the other hand, while non-renewable resources may be finite, they can be used up according to a plan and need not just disappear as a result of ignorant management.
The essence of good resource management depends upon two management attitudes which government policy needs to take into account:
- renewable resources need to be managed sustainably so that the ecosystems which supply them continue to be viable; and
- non-renewable resources have to be extracted in a manner that does not damage ecosystems irreparably.
A discussion of the resources of the Niger Delta contains too much information for one chapter and thus it has been broken down as follows:
- this current Chapter (eleven) covers land, water and fish;
- Chapter twelve covers forests;
- Chapter thirteen, soil and agriculture;
- Chapter fourteen, oil and gas; and
- Chapter fifteen, the impact of oil mining.
11.2 LAND
ECOZONE | APPROX. AREA | MAJOR ACTIVITIES |
Lowland Equatorial Monsoon (LEM) | 7400km² |
|
Freshwater (FAM) | 11700km² |
|
Brackish water (BAM) | 5400km² |
|
Sand Barrier Islands | 1140km² |
|
TOTAL | 25649km² |
In relation to the land resource in the Niger Delta, two issues need to be explained: reclamation and population density.
Human Population Density in the Niger Delta
The issue of land and human population density is important in relation to the development pressure that is put on the Niger Delta. At a glance the area seems to have a low population density compared with other parts of Southern Nigeria. However, close investigation shows that the amount of dry land upon which people can actually settle and farm is limited so that effectively the Niger Delta has the same population densities and pressures as the rest of Southern Nigeria.
A map appearing in a recent World Bank report (Defining an Environmental; Development strategy for the Niger Delta, 1995) shows a population density of 1.95 persons per hectare in Rivers State (now Rivers and Bayelsa States) compared to 6.18 and 7.12 for neighbouring Imo/Abia and Akwa Ibom States respectively. (Compared with Burundi at 2.9, Rwanda 3.5, India 2.1, Belgium 3.3, France 1.0).
This suggests that there is no population pressure in the Niger Delta. However the population densities of Ogoni undoubtedly match those of neighbouring Akwa Ibom, while other parts of the LEM ecozone and some of the Sand-barrier islands may not be far behind. Moreover, rural population densities on the limited islands of dry land in the Fresh-water ecozone appear to be equally high.
The situation is made worse because most of the Brackish-water ecozone (about 20% of the Niger Delta) is impossible to live on. The twin townships of Ogbolumabiri and Bassambiri (see map 11.) which make up Nembe are a good example. They are packed onto two islands largely made up of sand-fill and surrounded by mangrove forests that might as well be the sea; agricultural land is a few tens of hectares so that apart from for local shellfish all the food has to be imported.
Reclamation Dry land is created in the Fresh and Brackish-water ecozones, by sand-filling especially for urban expansion. For instance, Port Harcourt, Warri, Nembe, Ogbia and Brass, are largely built on sand-fill. This is not a modern phenomenon: nineteenth century European visitors to Warri commented on the spacious town, built on sand-fill. Smaller communities create land also: much of modern Sangana (discussed in detail in Chapter 19) is built on the sand dredged from the Sangana canal.
Also, throughout the mangrove forests, tiny settlements perch on Chicoco soil platforms dug out of the swamps, and reinforced with periwinkle and palm kernel shells. Similar reclamation occurs in the unofficial waterside settlement of the larger cities such as at Nembe Waterside in Port Harcourt where houses have to be raised up, and footpaths built on causeways, in order to remain dry during the long wet season. Such large settlements on Chicoco soil are not healthy because the water which dominates them is little better than sewage.
11.3 WATER
Water is the dominant feature of the Niger Delta. It is the sink into which the water of most of West Africa flows; and its estuaries are the drainage holes through which this water must pass. The condition of the water determines the condition of the Niger Delta and by studying the water and the life of the water we can obtain an idea about what is happening throughout the Niger/Benue river system.
The nature of Water, and Pollution
Without water there is no life, and access to drinking water is the prime factor in human settlement.
The irony of the Niger Delta is that while water dominates the physical environment, decent drinking water is hard to find: in the Brackish-water and Sandbarrier Island ecozones, the scarcity of drinking water has always determined the pattern of settlement. However in the Fresh-water and LEM ecozones, the availability of drinking water has only recently become a problem: because of pollution in the former, and in the latter because of falling water tables arising from forest clearance.
The tidal areas of the Brackish and Fresh-water ecozones are particularly susceptible to pollution in the dry season when the rivers are slow moving, so that pollutants are inefficiently flushed out as incoming tides tend to push them back upstream. This is graphically illustrated on the New Calabar River at Alu, North of Port Harcourt, where sump-oil from the Wills Brothers depot and spills from the bunkering operations at the Nigerian Institute of Oceanography, accumulate and merely move up and down the river with the tides.
In human terms much of the water in the Niger Delta is so polluted that illness and death from water-borne diseases are part of life. The most common water-borne illnesses are Diarrhoea, Dysentery and Cholera, and there is the ever-present danger of Typhoid and Guinea worm infection. Moreover parts of the Niger Delta are suitable environments for Bilharzia and River Blindness.
Details of the various water-borne diseases are as follows.
Diarrhoea: watery faeces which is often caused by water-borne bacteria in the gut.
Dysentery: caused by water-borne bacteria causing acute Diarrhoea in which blood is present.
Cholera: caused by water-borne bacteria causing chronic Diarrhoea and vomiting leading to death.
Typhoid: caused by water-borne bacteria which infect the gut causing symptoms similar to those of Malaria.
Guinea Worm - Dracunculatus dedinesis: the worm is taken into the system by drinking water contaminated with the water cyclops (tiny one-eyed crustaceans) that are infected with the Guinea Worm larvae. The cyclops is digested releasing the larvae that migrate into the abdominal tissues where they grow and mate. The males die but the females migrate to various parts of the body, most often the legs, and after about a year emerge in a painful blister. On contact with water the female releases eggs that thrive in still, shallow waters, but that die within three days if they do not find a water cyclops.
River Blindness - Onchocerciasis: caused by the parasitic filarial nematode, Onchocerca volvulus, it is transmitted to humans by the black fly (genus Simulium) which lives alongside rivers. The disease is endemic in much of Nigeria. The adult nematodes enter the skin of humans (the host) through the bite of the black fly (the intermediate host) as it makes a blood meal. A fibrous nodule develops in the skin which houses the adult nematodes that mate producing millions of microfilariae which migrate around the body (even to the eyes). When the black fly takes its next meal it ingests the microfilariae which develop into adults in the stomach wall, migrate to the head and proboscis (the feeding organ of the fly) ready to re-infect the human again. River Blindness is debilitating disease because after numerous infections, not only do the accumulated nodules cause ugly skin disorders and breakdown of the lymph glands but also insensitivity to light, loss of vision and eventually blindness.
Bilharzia - Schistosomiasis: caused by the liver fluke, Schistosoma haematobium, which thrives in still shallow waters. It is transmitted to humans, its host, through drinking contaminated water, and maintained in the ecosystem in the dry season in the snail Bulinus truncatus.
The flukes, which are larvae, are able to penetrate unbroken skin so that anyone who has regular contact with infested water is at risk. The larvae penetrate a surface vein and work their way through the blood system, into the heart, lungs, liver and abdomen, and thence back into the blood stream where they become adults, which lay eggs that are expelled from the body in blood from the damaged bladder and rectal veins. In the water the eggs hatch into ciliated larvae and search for a snail which they enter through the foot. Within the snail the larvae migrate to the liver and develop into sporocysts (sacs full of eggs) which eventually develop into larvae that break out of the snail as liver flukes. The whole process in the snail takes about three months or longer, allowing the S. haematobium to survive when its water habitat dries out.
Bilharzia is debilitating because it causes itchy skin and tissue deterioration, it erodes the blood vessels, causes internal bleeding, and the eggs are thought to cause cancer.
The problem for the Niger Delta is that there are no appropriate local controls over water pollution. Even if there were, the Delta is held hostage to the up-stream polluting activities of much of Nigeria and the countries within the Niger Benue basin, which include: Cameroon, the Benin Republic, Burkina Faso, Niger, Mali and Guinea.
Sources of Water Pollution
These include:
- domestic sewage and other organic wastes;
- infectious disease bacteria;
- fertiliser residues;
- pesticides and insecticides;
- industrial effluents;
- eroded sediments;
- other solid waste; and
- Petroleum.
Sewage and other organic wastes not only spread disease but also in decomposition have a high biological oxygen demand which may starve aquatic life of oxygen, particularly in the dry season when water movement is sluggish. Because of high water tables, pit latrines are difficult to construct in the Fresh and Brackish-water, and Sand Barrier Island ecozones. Thus public toilets float on the water beside settlements and human faeces falls directly into the water, often within yards of water collection points down-stream. In some districts bathhouses are part of the public toilets so that people immerse themselves in water that is separated from toilet water by no more than a few rotting planks. Ironically, these designs are recommended by the local authority, while simple technology exists to build healthy latrines in high water-table conditions on land.
Agricultural residues are not yet a major problem from within the Niger Delta. However, along with industrial effluents, they will increasingly become a problem arising up-river as Nigeria and the other counties in the Niger basin use more fertiliser and pesticides, and continue to industrialise (the River Niger is a prime site for industrial projects). A major source of local industrial pollution is the wastes of motor-boats.
Solid wastes mainly take the form of non-degradable manufactured items of which plastic is the prime offender, and farmers now complain about the amount of plastic bags which occur in the alluvium deposited on the seasonal flood plains.
Oil pollution is an epidemic throughout the Niger Delta, primarily as a result of careless management and the use of materials and standards that would not be acceptable in Europe and North America.
Canal Construction
Canals, known as Slots, built to give access to oil extraction facilities can damage local water resources and affect the salinity levels of water in the Fresh-water/Brackish-water ecotone. Detailed discussion of this problem is covered in Chapter 15.4.3.
Conclusion
It has to be said that the outlook for the purity of the Niger Delta's water is bleak, although international pressure in recent times has caused oil companies, at least, to reassess their responsibilities in the area.
11.4 FISH
11.4.1 AN INDICATOR ANIMAL FOR AQUATIC ECOSYSTEMS
The biomass, bioproductivity and biodiversity of fish in the Fresh-water ecozone depend upon three factors.
- The nutrients and solutes in the water, which are the beginnings of food chains, and which (in terms of individual chemicals) influence a wide range of physiological activities from nervous reactions, to breathing and breeding.
- Oxygen, which enters the water as a product of photosynthesis (by the phytoplankton and the higher plants), and directly from the atmosphere in fast and turbulent rivers. Not all the oxygen is available for the fish, which have to compete for it with other life forms, especially the decomposers. Also, turbidity reduces the ability of fish to take up oxygen through their Gills.
- Light, which decreases with depth and turbidity, and which influences oxygen levels from photosynthesis and the ability of fish to search for food.
Fish are so sensitive to their environment in terms of these factors that any decline in overall fish populations, in the weight of individual fish and/or in fish biodiversity, for a given ecosystem, suggests that something is going wrong. In this respect the health and the trends in the health of fish populations provide an indication of the health of aquatic ecosystems, just as birds make good indicators for terrestrial ecosystems. In this respect fish are often termed Indicator Species.
11.4.2 FRESH-WATER FISHING
Fresh-water fishing appears to be of less economic importance than fishing in the Saltwater ecozones. The catch is lower and both fishermen and women complain of declining catches. Many women say they catch only for the pot and that there is nothing left over for sale. This is borne out by investigations of local markets. Nonetheless the extensive floated lines and nets seen in the wider rivers suggest that despite turbidity and increasing pollution, fishing is a worthwhile economic activity. Moreover fish trapping in swamps, streams and lakes is a common practice.
The major fish species found in the Niger Delta and other Southern Nigerian fresh waters are well known to researchers, and there is a general opinion that they are underutilised. The potential for small-scale fish farming is high but river fishing is likely to beincreasingly limited by pollution and, in the white water rivers, by turbidity.
Common in the turbid waters of the Niger Delta are the Catfish, which do not have scales (classified as the animal order Siluriformes). One of the most common is the small (100-150mm) Chrysichthys nigrodigitatus which is yellow having spiny back and side fins. Also common is the slightly larger Mud-Catfish, Clarias anguillaris.
Of the scaly fish the large African River Pike, Hepsetus odoe, the small Moonfish, Citharinus latus, and many types of Tilapia are common.
Some of the more common fish are set out hereunder.
SOME FRESH-WATER FISH OF THE NIGER DELTA AND NEIGHBOURING RIVER SYSTEMS
Siluriformes
- Family Bagridae (Catfish): smooth skin, broad heads, wide mouths, concave tail fins, and the obvious 'whiskers' known as Barbels.
- Chrysichthys nigrodigitatus, large with a pointed snout.
- Bagrus docmak, flattened head.
- Auchenoglanis occidentalis, obvious 'leopard' spots.
- Family Clariidae (Mud Catfish) which are also able to breathe air with very primitive lung-like organs close to the Gills: differentiated from the Bagridae by a convex tail fin and very clear elongated fins along the back and belly.
- Clarias gariepinus, a small fish with obvious 'leopard' spots on its back.
- Clarias anguillaris, one of the smallest Mud catfish, having a stripy back.
- Heterobranchus bidorsalis, a large fish.
- Heterobranchus longifilis, also large.
Scaly Fish
- Family Cichlidae, the Tilapia and Tilapia-like fishes: small and scaly; vertically flat; long fins along their backs broken into segments, called Rays, by spines; and comparatively large tail fins.
- Order Characiformes: fish which have fins without rays, including a number of families which include the following species.
- Hydrocynus lineatus, the Tigerfish, having its distinct stripes along each row of horny scales.
- Hepsetus odoe, the African River Pike, being a large fish with big teeth.
- Citharinus latus and citharus, the Moonfish, having deep moon-shaped bodies.
11.4.3 INSHORE, ESTUARINE & BRACKISH-WATER FISHING (MARINE)
By contrast to the Fresh-water ecozones, fishing in these ecozones (which we call marine) is intense and has been well documented. Marine fish resources have been characterised as follows:
- Periwinkles, only utilised by local communities;
- Oysters, only utilised by local communities but suitable for culture;
- Squids, Cuttlefish and Octopi, which are incidental to bottom trawling but which have useful protein value;
- Crabs and Lobsters, which are largely under-used;
- Shrimps (sometimes known as Prawns or Cray-fish), which are seriously overfished;
- Sharks and related Sawfish, Rays, Scates and Mantas, which have very high quality meat; and
- the Bony Fish, which make up the majority of the catch, with about 80 utilised species including Croakers, Sole, Catfish, Snappers Barracuda, Bonga, Mackerel, Mullet, Sardines and Ribbonfish.
Protein: with fats and oils, and carbohydrates, the major component of living things. Protein is made up of molecules called Amino Acids, which form a variety of proteins essential to life - both structural (e.g. the protein that make up muscles) and functional (e.g. the proteins that make up enzymes used to trigger chemical reactions in the body). As with fats and carbohydrates, proteins are vital to the diet of animals and are most efficiently supplied by meat.
Marine fishing is a major economic activity in the Niger Delta. It is carried out in a number of ways by Local People: from the deep-sea boats with 4-6 crew and a couple of outboard motors, to simple throw nets on the seashore, to the collection of Molluscs in the mangrove forests.
As explained in Chapter 7, marine fishing throughout Nigeria and the whole of West Africa is dependent upon the mangrove forests of the Niger Delta. Moreover, the Nigerian fishing industry provides a great deal of employment and economic opportunity because it is labour intensive and dominated by the small fishermen who were still taking up to 90% of the national marine catch in the late 1980s.
11.4.4 THE DECLINE OF MARINE FISHING
Environmental damage to the Niger Delta and over-fishing throughout the region is a threat to the Nigerian marine fishing industry. It has been suggested in the Natural Resources Conservation Action Plan, that the sustainable marine catch (excluding the deep sea) is 190,000 tonnes a year. However, between 1980 and 1986 annual recorded catches ranged between 137,000 and 370,000 tonnes on a declining plain, and fishermen complain that their catches are going down. Deep-sea trawler catches have declined similarly from a peak of 535,000 tonnes in 1979, to 286,000 in 1986, but over the same period, trawler numbers increased from 92 in 1979, to 440 in 1989. Also, the mean length of trawled fish has declined between 1981 and 1990, for example, as follows:
Length in cms | 1981 | 1991 |
Croaker | 32.32 | 26.41 |
Soles | 32.88 | 25.47 |
Threadfin | 24.08 | 20.81 |
It is interesting that fishermen from Ondo State have been moving into the Niger Delta because they cannot compete with Lagos trawlers. But the trawlers have been following them, resulting in confrontation with local fishermen.
A 1980 to 1989 survey (Nigerian Federal Department of Fisheries Statistics 2nd Edition) of trawler catches brought to Lagos showed the following worrying average, as annual tonnes per trawler of specific fish caught (sample figures only):
Tonnes/Trawler | 1980 | 1985 | 1989 |
Croaker | 739 | 403 | 52 |
Soles | 82 | 89 | 19 |
Catfish | 218 | 3 | 0 |
Snappers | 105 | 27 | 16 |
Barrracuda | 159 | 21 | 7 |
11.4.5 THE FUTURE OF THE FISHING INDUSTRY
The Niger Delta and national fish catches are declining, and the only option for Nigeria's future fishing industry has four necessary and interdependent parts:
- A limitation of marine fishing.
- Maintenance of the mangrove forests as the foundation of the fish life cycle.
- Increased fish farming in the Fresh-water ecozone.
- Increased fish farming in the Brackish-water ecozone, without compromising its vital place in initiating the marine food chain.
In the fresh-water ecozones fish farms can be encouraged on a small-scale, which can be maintained by a single family. The fish can be fed on household waste, rats, lizards, fish intestines, poultry manure and easily grown crops such as Plantains, Papaya and Cassava. What is needed is a secure supply of young fish, (fingerlings).
Because of the high level of nutrients in the water, mangrove environments are ideal for farming fish in cages, enclosures and ponds. Nonetheless large areas of mangroves have been destroyed in Southeast Asia for Prawn and Shell fish farms, and similar activity in the Niger Delta would be counter productive in relation to deep-sea, inshore and estuarine fishing. However the nutrient rich environment can be used to increase the national fish yield by raising of fingerlings in ponds to be released into the creeks; rather in the manner of seeding mountain streams with trout.