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Robert Whaples



Robert Whaples earned his Ph.D. in economics from the University of Pennsylvania in 1990. He is Chair of the Department of Economics at Wake Forest University and Director of EH.NET, which provides economic history services to the worldwide public at www.eh.net. His course, Modern Economic Issues, is available on CD and DVD from the Teaching Company.

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International Society for Ecological Economics
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The International Society for Ecological Economics (ISEE) is a not-for-profit, member-governed, organization dedicated to advancing understanding of the relationships among ecological, social, and economic systems for the mutual well-being of nature and people. The ISEE facilitates understanding between economists and ecologists and the integration of their thinking into a trans-discipline aimed at developing a sustainable world.

The ISEE’s flagship publication is the journal Ecological Economics, that publishes scholarly work on issues such as valuation of natural resources, sustainable agriculture and development, ecologically integrated technology, integrated ecologic-economic modelling at scales from local to regional to global, and integrating natural resources and environmental services into national income and wealth accounts.

Website: ISEE home page

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Featured Environmental Classic

Undersea (historical)



Originally Published As:
Title: Undersea
Author: Rachel Louise Carson
Source: Atlantic Monthly, 78 (September 1937), pp. 55–67
Year published: 1937


EDITOR'S NOTE: This paper is among Carson's earliest published work. It was originally titled “The World of Waters” and was written as an introduction to a U.S. Bureau of Fisheries brochure in 1935. She was encouraged to submit it to Atlantic Monthly, where it was published by editor Edward Weeks. Its publication marked Carson’s literary debut as a writer of critical merit. “Undersea” subsequently became the basis of Carson’s first book, Under the Sea-Wind (1941). “Undersea” introduces two of Carson’s signature themes: the ancient and enduring ecology that dominates ocean life, and the material immortality that encompasses even the smallest organism. From these four pages in Atlantic Monthly, Carson later admitted, “everything else followed.”


Who has known the ocean? Neither you nor I, with our earth-bound senses, know the foam and surge of the tide that beats over the crab hiding under the seaweed of his tidepool home; or the lilt of the long, slow swells of mid-ocean, where shoals of wandering fish prey and are preyed upon, and the dolphin breaks the waves to breathe the upper atmosphere. Nor can we know the vicissitudes of life on the ocean floor, where the sunlight, filtering through a hundred feet of water, makes but a fleeting, bluish twilight, in which dwell sponge and mollusk and starfish and coral, where swarms of diminutive fish twinkle through the dusk like a silver rain of meteors, and eels lie in wait among the rocks. Even less is it given to man to descend those six incomprehensible miles into the recesses of the abyss, where reign utter silence and unvarying cold and eternal night.

To sense this world of waters known to the creatures of the sea we must shed our human perceptions of length and breadth and time and place, and enter vicariously into a universe of all-pervading water. For to the sea’s children nothing is so important as the fluidity of their world. It is water that they breathe; water that brings them food; water through which they see, by filtered sunshine from which first the red rays, then the greens, and finally the purples have been strained; water through which they sense vibrations equivalent to sound. And indeed it is nothing more or less than sea water, in all its varying conditions of temperature, saltiness, and pressure, that forms the invisible barriers that confine each marine type within a special zone of life – one to the shore line, another to some submarine chasm on the far slopes of the continental shelf, and yet another, perhaps, to an imperceptibly defined stratum at mid-depths of ocean.

There are comparatively few living things whose shifting pattern of life embraces both land and sea. Such are creatures of the tide pools among the rocks and of the mud flats sloping away from dune and beach grass to the water’s edge. Between low water and the flotsam and jetsam of the high-tide mark, land and sea wage a never-ending conflict for possession.

As on land the coming of night brings a change over the face of field and forest, sending some wild things into the save retreat of their burrows and bringing others forth to prowl and forage, so at ebb tide the creatures of the waters largely disappear from sight, and in their place come marauders from the land to search the tide pools and to probe the sands for the silent, waiting fauna of the shore.

Twice between succeeding dawns, as the waters abandon pursuit of the beckoning moon and fall back, foot by foot, periwinkle and starfish and crab are cast upon the mercy of the sands. Every heap of brine-drenched seaweed, every pool forgotten by the retreating sea in recess of sand or rock, offers sanctuary from sun and biting sand.

In the tide pools, seas in miniature, sponges of the simpler kinds encrust the rocks, each hungrily drawing in through its myriad mouths the nutriment-laden water. Starfishes and sea anemones are common dwellers in such rock-grit pools. Shell-less cousins of the snail, the naked sea slugs are spots of brilliant rose and bronze, spreading arborescent gills to the waters, while the tube worms, architects of the tide pools, fashion their conical dwellings of sand grains, cemented on against another in glistening mosai.

On the sands the clams burrow down in search of coolness and moisture, and oysters close their all-excluding shells and wait for the return of the water. Crabs crowd into damp rock caverns, where periwinkles cling to the walls. Colonies of gnome-like shrimps find refuge under dripping strands of brown, leathery week heaped on the beach.

Hard upon the retreating sea press invaders from the land. Shore birds patter along the beach by day, and legions of the ghost crab shuffle across the damp sands by night. Chief, perhaps, among he plunderers is man, probing the soft mud flats and dipping his nets into the shallow waters.

At last comes a tentative ripple, then another, and finally the full, surging sweep of the incoming tide. The folk of the pools awake-clams stir in the mud. Barnacles open their shells and begin a rhythmic sifting of the waters. One by one, brilliant-hued flowers blossom in the shallow water as tubeworms extend cautious tentacles.

The ocean is a place of paradoxes. It is the home of the great white shark, two-thousand-pound killer of the seas, and of the hundred-foot blue whale, the largest animal that ever lived. It is also the home of living things so small that your two hands might scoop up as many of them as there are stars in the Milky Way. And it is because of the flowering of astronomical numbers of these diminutive plants, known as diatoms, that the surface of waters of the ocean are in reality boundless pastures. Every marine animal, from the smallest to the sharks and whales, is ultimately dependent for its food upon these microscopic entities of the vegetable life of the ocean. Within their fragile walls, the sea performs a vital alchemy that utilizes the sterile chemical elements dissolved in the water and welds them with the torch of sunlight into the stuff of life. Only through this little-understood synthesis of proteins, fats, and carbohydrates by myriad plant “producers” is the mineral wealth of the sea made available to the animal “consumers” that browse as they float with the currents. Drifting endlessly, midway between the sea of air above and the depths of the abyss below, these strange creatures and the marine inflorescence that sustains them are called “plankton” – the wanderers.

Many of the fishes, as well as the bottom-dwelling mollusks and worms and starfish, begin life as temporary members of this roving company, for the ocean cradles their young in its surface waters. The sea is not a solicitous foster mother. The delicate eggs and fragile larvae are buffeted by storms raging across the open ocean and preyed upon by diminutive monsters, the hungry glass worms and comb jellies of the plankton.

These ocean pastures are also the domain of vast shoals of adult fishes: herring, anchovy, menhaden, and mackerel, feeding upon the animals of the plankton and in their turn preyed upon; for here the dogfish hunt in packs, and the ravenous bluefish, like roving buccaneers, take their booty where they find it.

Dropping downward a scant hundred feet to the white sand beneath, an undersea traveler would discover a land where the noonday sun is swathed in twilight blues and purples, and where the blackness of midnight is eerily aglow with the cold phosphorescence of living things. Dwelling among the crepuscular shadows of the ocean floor are creatures whose terrestrial counterparts are drab and commonplace, but which are themselves invested with delicate beauty by the sea. Crystal cones form the shells of pteropods or winged snails hat drift downward from the surface to these dim regions by day; and the translucent spires of lovely ianthina are tinged with Tyrian purple.

Other creatures of the sea’s bottom may be fantastic rather than beautiful. Spine-studded urchins, like rotund hedgehogs of the sea, tumble over the sands, where mollusks lie with slightly opened shells, busily straining the water for debris. Life flows on monotonously for these passive sifters of the currents, who move little or not at all from year to year. Among the rock ledges, eels and cunners forage greedily, while the lobster feels his way with nimble wariness through the perpetual twilight.

Farther out on the continental shelf, the ocean floor is scarred with deep ravines, perhaps the valleys of drowned rivers, and dotted with undersea plateaus. Hosts of fish graze on these submerged islands, which are richly carpeted with sluggish or sessile forms of life. Chief among the ground fish are haddock, cods, flounders and their mightier relative, the halibut. From these and shallower waters man, the predator, exacts a yearly tribute of nearly thirty billion pounds of fish.

If the underwater traveler might continue to explore the ocean floor, he would traverse miles of level prairie lands; he would ascend the sloping sides of hills; and he would skirt deep and ragged crevasses yawning suddenly at his feet. Through the gathering darkness, he would come at last to the edge of the continental shelf. The ceiling of the ocean would lie a hundred fathoms above him, and his feet would rest upon the brink of a slope that drops precipitously another mile, and then descends more gently into an inky void that is the abyss.

What human mind can visualize conditions in the uttermost depths of the ocean? Increasing with every foot of depth, enormous pressures reach, three thousand fathoms down, the inconceivable magnitude of three tons to every square inch of surface. In these silent deeps a glacial cold prevails, a bleak iciness which never varies, summer or winter, years melting into centuries, and centuries into ages of geologic time. There, too, darkness reigns – the blackness of primeval night in which the ocean came into being, unbroken, through eons of succeeding time, by the gray light of dawn.

It is easy to understand why early students of the ocean believed these regions were devoid of life, but strange creatures have now been dredged from the depths to bear mute and fragmentary testimony concerning life in the abyss.

The “monsters” of the deep sea are small, voracious fishes with gaping, tooth-studded jaws, some with sensitive feelers serving the function of eyes, other bearing luminous torches or lures to search out or entice their living prey. Through the night of the abyss, the flickering lights of these foragers move to and fro. Many of the sessile bottom dwellers glow with a strange radiance suffusing the entire body, while other swimming creatures may have tiny, glittering lights picked out in rows and patterns.

The deep-sea prawn and the abyssal cuttlefish eject a luminous cloud, and under cover of this pillar of fire escape from their enemies.

Monotones of red and brown and lusterless black are the prevailing colors in the deep sea, allowing the wearers to reflect the minimum of the phosphorescent gleams, and to blend into the safe obscurity of the surrounding gloom.

On the muddy bottom of the abyss, treacherous oozes threaten to engulf small scavengers as they busily sift the debris for food. Crabs and prawns pick their way over the yielding mud on stilt-like legs; sea spiders creep over sponges raised on delicate stalks above the slime.

Because the last vestige of plant life was left behind in the shallow zone penetrated by the rays of the sun, the inhabitants of these depths contrast strangely with the self-supporting assemblage of the surface waters. Preying one upon another, the abyssal creatures are ultimately dependent upon the slow rain of dead plants and animals from above. Every living thing of the ocean, plant and animal alike, returns to the water at the end of its own life span the materials that had been temporarily assembled to form its body. So there descends into the depths a gentle, never-ending rain of the disintegrating particles of what once were living creatures of the sunlit surface waters, or of those twilight regions beneath.

Here in the sea mingle elements which, in their long and amazing history, have lent life and strength and beauty to a bewildering variety of living creatures. Ions of calcium, now free in the water, were borrowed years ago from the from the sea to form part of the protective armor of a mollusk, returned to the main reservoir when their temporary owner had ceased to have need of them, and later incorporated into the delicate statuary of a coral reef. Here are atoms of silica, once imprisoned in a layer of flint in the subterranean darkness; later, within the fragile shell of a diatom, tossed by waves and warmed by the sun; and again entering into the exquisite structure of a radiolarian shell, that miracle of ephemeral beauty that might be the work of a fairy glass-blower with a snowflake as his pattern.

Except for the precipitous slopes and regions swept bare by the submarine currents, the ocean floor is covered with primeval oozes which have been accumulating for eons deposits of varied origins; earth-born materials freighted seaward by rivers or worn from the shores of continents by the ceaseless grinding of waves; volcanic dust transported long distances by wind, floating lightly on the surface and eventually sinking into the depths to mingle with the products of no less mighty eruptions of submarine volcanoes; spherules of iron and nickel from interstellar space; and substances of organic origin – the siliceous skeletons of Radiolaria and the frustules of diatoms, the limey remains of algae and corals, and the shells of minute Foraminifera and delicate pelagic snails.

While the bottoms near the shore are covered with detritus from the land, the remains of the floating and swimming creatures of the sea prevail in the deep waters of the open ocean. Beneath tropical seas, in depths of 1000 to 1500 fathoms, calcareous oozes cover nearly a third of the ocean floor; while the colder waters of the temperate and polar regions release to the underlying bottom the siliceous remains of diatoms and Radiolaria. In the red clay that carpets the great deeps at 3000 fathoms or more, such delicate skeletons are extremely rare. Among the few organic remains not dissolved before they reach these cold and silent depths are the ear bones of whales and the teeth of sharks.

Thus we see the parts of the plan fall into place: the water receiving from earth and air the simple materials, storing them up until the gathering energy of the spring sun wakens the sleeping plants to a burst of dynamic activity, hungry swarms of planktonic animals growing and multiplying upon the abundant plants, and themselves falling prey to the shoals of fish; all, in the end, to be redissolved into their component substances when the inexorable laws of the sea demand it. Individual elements are lost to view, only to reappear again and again in different incarnations in a kind of material immortality. Kindred forces to those which, in some period inconceivably remote, gave birth to that primeval bit of protoplasm tossing on the ancient seas continue their mighty and incomprehensible work. Against this cosmic background the life span of a particular plant or animal appears, not as a drama complete in itself, but only as a brief interlude in a panorama of endless change.

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Featured Map

Jamaican moist forests



Introduction

Jamaica (Photograph by Leo R. Douglas)

The moist forests of this ecoregion are characterized by rich floral and faunal diversity. In contrast to the rest of the Caribbean archipelago, Jamaica was never connected to another landmass. As a result, the island has a particularly high proportion of endemic plant and animal species. Two notable forest areas in this ecoregion are the Blue and John Crow Mountains and Cockpit Country. Deforestation rates in this ecoregion are very high; however, due to the establishment of new protected area and management systems these rates should be slowing as logging is prohibited. Although a lack of adequate environmental legislation and enforcement seems the obvious impediments to conservation, the fundamental problem in Jamaica as in many other areas is the pervasive poverty that must be overcome.

Location and General Description

Jamaica is the 3rd largest island of the Caribbean archipelago, is approximately 230 kilometers(km) long, 80 km wide at the center, and covers an area of approximately 11,500 square kilometers (km2). The island of Jamaica, which emerged from the ocean in the mid-Miocene, has never been connected to any other landmass. Jamaica ranks fifth among the world's islands and with the highest percentage of endemic flora. The island consists of two main mountain ranges, the John Crow Mountains in the east, which are limestone outcroppings, reaching a maximum height of 1,000 meters (m), and the Blue mountains, which are igneous shale reaching 2,290 m. The southern coastal plains are broad, and include flat alluvial areas, swamps, and dry hills of the neighboring ecoregions. The land surface is two-thirds limestone, the rest is composed of igneous rocks, sedimentary shale, and alluvium. Mean annual rainfall varies from less than 750 millimeters(mm) to more than 7,000 mm; rainfall increases with elevation.

This ecoregion comprises approximately 85% of Jamaica’s terrestrial area and covers all of the island except coastal areas and lowland dry forests. At present, only the most remote and inaccessible forests on Jamaica are considered original and undisturbed. In 1983, less than 67,000 hectares (ha) (6%) of Jamaica was covered in undisturbed natural forest. In 1995, the World Resources Institute ranked it as the country with the highest deforestation rate. Three broad groups of forest occur in this ecoregion: limestone forests, predominantly shale forests, and alluvial and wetland forests of the coastal plains. Development threatens this ecoregions forests as coastal residents seek to escape the high temperatures of lower elevations. The WWF/IUCN study publication; Centers of Plant Diversity and Endemism recognizes 2 critical areas in Jamaica, totaling 700 km2 (the Blue and John Crow Mountains and Cockpit Country). The limestone forest flora of the Blue and John Crow Mountains contains more than 600 species of flowering plants and includes about 275 vascular plant species and 14 varieties which are endemic to Jamaica. About 87 vascular plant species or 33% of Jamaica’s endemic vascular plant flora, are strictly endemic to the Blue and John Crow Mountains.

Cockpit Country consists of evergreen seasonal forest, mesic limestone forest, and degraded mesic limestone forest. In valleys, human interference has resulted in areas of pasture and some agricultural crops. The whole region is estimated to contain 1500 vascular plant species, of which 400 are endemic to Jamaica, including 100 species of angiosperms and one species of fern which are strictly endemic to the Cockpit Country. According to Proctor, there are 106 species which, in Jamaica, are only found in the Cockpit Country. Strict endemic species are best represented in the families Rubiaceae(11 spp.), Compositae (9 spp.), Gesneriaceae (8 spp.), Euphorbiaceae (7 spp.), Orchidaceae (7 spp., in the genus Lepanthes), and Myrtaceae (6 spp.). Floristic studies indicate that each limestone knoll can support distinctly different plants, including those which are endemic to just one knoll.

Biodiversity Features

Of 3,003 species of flowering plants recorded from Jamaica, 830 (28%) are endemic; of 579 fern species 82 (14%) are endemic; and within the Bromeliaceae and Orchidaceae, both of which are richly represented on Jamaica, endemism is 31%.

More than twenty endemic birds species occur (more than on any other oceanic island in the world) on the island of Jamaica with the number of species almost doubling in the winter due to the arrival of migrants from North America. Most of the birds occur in the forests throughout the island, an exception being the recently split red-billed and black-billed streamertails (Trochilus polytmus and T. scitulus) the latter of, which is confined to eastern Jamaica including the Blue Mountains. Many of the bird species are suffering declining population numbers due to habitat loss and illegal hunting for foreign collectors or by farmers for crop protection. The endemic Jamaican least pauraque (Siphonorhis americanus) is thought to be extinct, but some scant evidence suggests it may still survive.

Reptile and amphibian diversity is equally rich as is represented by the number of endemics. Jamaica boasts 27 island endemic reptile species and 20 island endemic amphibian species. Endemics specific to this forest ecoregion are Sphaerodactylus richardsoni, S. semasiops, Anolis garmani, A. reconditus, Eleutherodactylus grabhami E. griphus, E. jamaicensis, E. junori, E. luteolus, E. nubicola, E. orcuttia, E. pantoni, and E. sisyphodemus. The Indian Mongoose (Herpestes auropunctatus), first introduced to Jamaica in 1872, is an adaptable species that has had a profound effect on native vertebrates, especially reptiles and amphibians. Several endemic butterflies, (Papilio homerus, Eurytides marcellinus) and most of the more than 500 endemic species of Jamaican snails (e.g., Pleurodonte spp. and Annularian pulchrum) are found in this moist ecoregion.

There are three island endemic bats on Jamaica (Artibeus flavescens, Phyllonycteris aphylla, Eptesicus lynni). The sole remaining extant native mammal of Jamaica, the Jamaican hutia (Geocapromys brownii), is found mostly in the remote mountainous regions of eastern, central, and southern Jamaica where it is threatened by hunting pressure and habitat loss.

Current Status

Jamaica has a protected area network with 40 parks and reserves, however, these are largely unmanaged, unmonitored, and neither hunting nor habitat encroachment are effectively controlled. Staff shortages in relevant agencies are acute and fines for violators of environmental legislation, following successful prosecution, are minimal. In the 1980s the principal obstacles faced when attempting to develop a working park system included lack of public awareness, political support, protected area legislation, and comprehensive park system policy statement. At the same time the need for definition and restriction of management capacity in priority areas developed.

Types and Severity of Threats

Leading environmental concerns include deforestation, soil erosion, population pressures, and lack of public awareness concerning conservation. Mining for a variety of minerals, chiefly limestone, is a serious threat to many of the forests in central Jamaica many of which have never been scientifically assessed. Mining has had a major impact, with bauxite (aluminum ore) mining being particularly important. Perhaps the most immediate serious threat is deforestation as a result of large and small-scale cultivation, principally on the southern slopes of the Blue Mountains, but also in other areas. Deforestation causes massive soil erosion and the quality of the land deteriorates rapidly. Water-courses leading from the mountains become heavily laden with sediment and water flows decrease and become more erratic. This results in water shortages alternating with floods at lower altitudes. Until recently, interior forests were very inaccessible, however, continued road construction into these areas will inevitably lead to increased deforestation and selective cutting.

Justification of Ecoregion Delineation

Our classification for the moist forests of Jamaica are based on conglomerations of the following moist forest types/formations according to Grossman et al and Brown and Heinman: limestone forest and ruinate, virgin forest, mist forest, and elfin woodland, and wet forest fringes and related river valleys. Our classification does not separate out montane formations, which occur between 900 - 1,500 m.

Additional Information on this Ecoregion

Further Reading

  • Allen, B. 1990. National park planning in Jamaica: a project in sustainable development and conservation. Paper presented to the Association of Caribbean Studies Conference on the Caribbean Environment, Santo Domingo, Dominican Republic.
  • Anon. 1987. Jamaica: country environmental profile. Kingston, Jamaica: Government of Jamaica, Ministry of Agriculture, NRCD and R. M. Field Associates, Inc.
  • Anon. 1989. Conservation of Forest Ecosystems. National Forestry Action Plan Jamaica. Report coordinated by C. Weber. 75 pp.
  • Brown, F. M., and B. Heineman. 1972. Jamaica and its butterflies. E.W. Classey Limited, London, UK. ISBN: 0900848448
  • CCA. 1996. Economic and financial evaluation of Buccoo Reef Marine Park: Management options. Prepared by Simmons and Associates for the Caribbean Conservation Association.
  • Collar, N. J. and P. Andrew. 1988. Birds to watch: the ICPB world checklist of threatened birds. Cambridge: ICBP Technical Publication, No. 8.
  • Davis, S. D., V. H. Heywood, O. Herrera-MacBryde, J. Villa-Lobos, and A. C. Hamilton, editors. 1997. Centres of plant diversity: a guide and strategy for their conservation (Volume 3. The Americas). WWF-World Wide Fund for Nature and IUCN-The World Conservation Union. IUCN. IUCN Publications Unit, Cambridge, U.K. ISBN: 283170197X
  • Davis, S. D., S. J. M. Droop, P. Gregerson, L. Henson, C. J. Leon, J. Villa-Lobos, H. Synge, and J. Zantovska. 1986. Plants in danger. What do we know? Gland, Switzerland and Cambridge, U.K.: IUCN. ISBN: 2880327075
  • Downer A. and R. Sutton. 1990. Birds of Jamaica: a photographic field guide. Cambridge University Press. Cambridge. ISBN: 0521383099
  • Greenway, J. C. 1967. Extinct and vanishing birds of the world. 2nd Ed. Dover Publications. New York. ISBN: 0486218694
  • Grossman, D.H., S. Iremonger, D.M. Muchoney. 1993. Jamaica: map of natural communities and modified vegetation types. Jamaica: a rapid ecological assessment. Phase 1: An island-wide characterization of mapping of natural communities and modified vegetation types. The Nature Conservancy, Washington, D.C., USA.
  • Hoagland, P., M. E. Schumacher, and A. G. Gaines, Jr. 1995. Toward an effective protocal on land-based marine pollution in the wider Caribbean region. WHOI-95-10. Prepared by Woods Hole Oceanographic Institution (WHOI) for the U.S., Woods Hole Massachusetts.
  • Johnson, T. H. 1988. Biodiversity and conservation in the Caribbean: profiles of selected islands. International Council for Bird Preservation, Monograph No. 1, Cambridge UK. ISBN: 0946888140
  • Mittermaier, R. A., N. Myers, and C. G. Mittermaier editors. 1999. Hotspots: earth’s biologically richest and most endangered terrestrial ecosystems. Toppan Printing Company, Japan.
  • Proctor, G.R. 1986. Cockpit Country and its vegetation. In D.A. Thompson, P.K. Bretting, and M. Humphries, editors. Forests of Jamaica. The Jamaican Association of Scientists and Technologists, Kingston, Jamaica. Pp. 43-47, 140-143.
  • Stattersfield, A. J., M. J. Crosby, A. J. Long, and D. C. Wege. 1998. Endemic bird areas of the world: priorities for biodiversity conservation. Birdlife Conservation Series 7. Birdlife International, Cambridge, U.K.
  • Stoffers, A. L. 1993. Dry coastal ecosystems of the West Indies. In E. van der Maarel, editor, Ecosystems of the world 2B: dry coastal ecosystems Africa, America, Asia and Oceania. Elsevier Science Publishers, B.V., Amsterdam.
  • Thorsell, J.W. 1981. Towards a national park system for Jamaica. Natural Resources Conservation Department, Ministry of Mining and Energy.



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Country Profile

Water profile of Barbados



Geography and population

Barbados (13°10' North, 59°32' West) is an independent island nation. It is the most easterly of the Eastern Caribbean islands. It has a land area of 430 kilometers2 with the highest point rising to 323 meters near the center of the island. About five-sixths of the island are coraline in nature, with the remaining one-sixth of shales, sands and clays known as the Scotland District. The Scotland District though quite rugged is known for its land slips and erosion problems. The coraline area is characterized by a number of terraces rising towards the interior of the island, and deep gullies from the higher elevations (bordering the Scotland District) radiating to the coast. Cultivable land is estimated at 22,472 hectares (ha), of which the cultivated area in 1997 was 17,000 ha, 16,000 for annual and 1,000 ha for permanent crops. The major crops grown are sugar cane, cotton, root crops and vegetables. For administrative purposes, the country is divided into 15 provinces or parishes.

Map of Barbados. (Source: FAO-Forestry)

The population census of 1990 recorded 260,491 residents, mainly concentrated in the urban corridor along the west coast, south coast and Bridgetown, the capital (located in the southwest). Population growth rate averaged about 0.27% from 1990 to 1997. There are well established and accessible health and education institutions, potable water to the entire population, well developed local and international transport links and telecommunications infrastructure. The main foreign currency earners are tourism and agriculture. Agriculture (non-sugar, sugar and fisheries) contributed 6.3% and 4.9% to gross domestic product (GDP) in 1996 and 1997 respectively, and employed 5.1% of the labor force in 1997.

Climate and water resources

Climate

Barbados has a tropical oceanic climate with a cooling influence from the northeast trade winds. Average daytime temperature is about 29°C ranging from 20 to 32°C. The average annual rainfall is 1,422 mm with the wet (hurricane) season from June to December. In the dry season, rainfall may be less than 25 milimeters/month.

Water resources

Annual internal renewable water resources (IRWR) were estimated in a 1997 Water Resources Study to total about 82 million m3. Groundwater derived from infiltrated rainfall accounts for 73.9 million m3; surface water amounts to 5.8 million m3; springs 2.0 million m3 and direct runoff to the sea 0.5 million m3.

Water withdrawal

Exact quantities of water withdrawal are unknown since irrigation applications are rarely ever calculated, as total metering is only now being implemented for all abstractions and connections to the potable supply. Annual water withdrawal in the agriculture sector in 1996 was estimated at 19.01 million m3 (not including golf course irrigation at 0.9 million m3) whereas the domestic, municipal and industrial sector accounted for 25.85 million m3. Unaccounted water was about 35 million m3.

Almost all of the island's potable water is pumped from 21 groundwater wells in the karstic coraline area of the island, and small quantities obtained from two springs in the Scotland District. Water is treated with chlorine to meet World Health Organization (WHO) and U.S. Environmental Protection Agency (EPA) guidelines and standards, prior to distribution. In the east of the island, there are a few relatively small rivers fed by spring sources, and ephemeral streams that flow during rain events. During the dry season (January to June) there can be water shortages in the potable supply to some areas. The use of water for other non-essential purposes is then prohibited island-wide. There is a sewerage system in place servicing the Bridgetown area.

Irrigation and drainage development

Irrigation potential was estimated in 1998 at 3,587 ha. In estimating this figure, consideration was given to land capability and maintaining safe yields from the groundwater supplies. The 1989 agricultural census indicated an irrigated area of about 1,000 ha. The island's potable water supply is used extensively by small farmers as their irrigation water supply. There are about 120 private hand-dug wells which are mainly used for irrigation. In the past many of the shallower wells were equipped with windmills but today the electric submersible pump is the norm. There is some relatively limited use of dams, springs, streams, roof catchments and road-catchments.

There is extensive use of conventional sprinkler systems and drip micro-irrigation systems for vegetable, fruit and horticultural crops. Drip irrigation has been widely used especially in the past ten years both by farmers and for landscaping. There is no surface irrigation (basin, furrow, flood recession) in the conventional sense, but the term is used to include the use of garden-hose flooding and hand-watering. The Government offers rebate incentives for the use of sprinkler and drip irrigation systems.

There are two Government-financed and operated irrigation schemes providing a piped, on-demand, pressurized water supply. In the north of the island, there is the Spring Hall Land Lease Project (land settlement project) with 22 farmer/family leased plots of land averaging about 10 ha each. The second scheme is the Rural Development Programme in the south, made up of nine individual irrigation systems servicing over 250 farmer-owned plots averaging under one hectare each. The systems are now quite dependable and small farmers rely upon them heavily during the dry season. Water charges are respectively US$16 cents and 22 cents per cubic meter of water used (compared to US$1.06 commercial rate for the potable supply). Regularly produced crops include tomatoes, cucumbers, hot peppers, sweet peppers, onion, carrot and beet. Other irrigated crops include citrus, bananas, plantains and cut-flowers. Irrigated vegetable farmers can get three crops in a season.

There is relatively little wastewater reuse at present for irrigation. A few hotels treat their wastewater and re-use it for irrigating lawns and gardens. Also a number of private homes run part of their wastewater to fruit trees or small banana patches in the backyard.

There is little drainage work carried out by private farmers. In some areas, beds are raised in the wet season to facilitate better drainage in the root zone. Generally, none of the drainage work is traditionally linked to surface irrigation or a high water table. The Soil Conservation Unit of the Ministry of Agriculture has carried out substantial land stabilization works in the Scotland District. The drainage of surface and subsurface flows is essential for this land stabilization. The flows are channeled safely via gabion structures to storage reservoirs or to stream courses which flow into the sea. Little of this water is now used for irrigation, and little quantification is made of the stream flow and irrigation potential in the area. Plans are being put in place to utilize some of this water for irrigation.

Institutional environment

The Barbados Water Authority (BWA) is the institution with overall responsibility for the development, management and assessment of the island's water resources. BWA supplies all potable water and also operates the Bridgetown Sewerage System. All abstractions from wells, streams and rivers must be approved and licensed by the BWA. There is currently no abstraction fee but there are plans to implement this in the near future.

Generally, development of irrigation rests with the Land and Water Use Unit of the Ministry of Agriculture and the Irrigation Unit of the Barbados Agricultural Development and Management Corporation (a Government corporation), which operates and maintains the two public irrigation schemes. They have no regulatory mandate. The Soil Conservation Unit of the Ministry of Agriculture must be consulted on all development in the Scotland District.

Water quality and environmental pollution matters fall within the mandate of the Environmental Engineering Division while public health water-related matters fall to the Public Health Inspectorate. Both are sections within the Ministry of Health. In 1963, the Government instituted a policy (revised in 1973) which created a system of five Groundwater Protection Zones implemented across the island to guard against bacteriological contamination of the public water supply wells. The most stringent regulations are enforced in the Zone I area which is located immediately around all existing and potential public water supply sites. Zones 2 to 5 provide progressively less stringent controls. The policy, however, does not address chemical contamination and still needs specific legislative authority.

Relevant water resources conservation legislation includes the Barbados Water Authority Act (1980), the Underground Water Control Act (1953), the Three Houses Act (1713) and the Porey Spring Act.

Trends in water resources management

The 1997 Water Resources Study suggests that unaccounted-for water in the BWA's potable water supply approaches 60%. There are ongoing efforts to reduce this level by at least 30% with several measures including the implementation of tariff increases to control demand. Contracts have been signed for the construction of a 6 million m3/y brackish water desalination plant to augment the potable water supply. A Draft Policy Framework for Water Resources Development and Management for Barbados is in preparation.

Construction is well advanced on a sewerage system to service the south coast and plans are approved for a system for the west coast by 2005. Wastewater from these systems together with the Bridgetown system will amount to about 11 million m3/y, and is now being considered as a water resource for golf course irrigation, as a buffer to seawater intrusion along the west coast and other uses.

Licensing and a usage fee will be implemented for all agricultural (and other) abstractions in an attempt to control and monitor water use.

Sprinkler and drip irrigation systems are now well accepted by the farming community. The focus will now be to optimize irrigation water use efficiencies. Further development of farming districts similar to the Rural Development Programme with dedicated (public or private financed) irrigation systems, will encourage farmers to reduce their dependence on the potable (chlorinate) water supply, and allow them access to lower rates for irrigation water.

There are recommendations for the implementation of a Code of Agricultural Practice to address potential pollution problems attributed to pesticides, herbicides, and fertilizers in agriculture.

Further reading

  • Water profile of Barbados, Food and agriculture Organization.
  • World Factbook: Barbados, Central Intelligence Agency.
  • Town and Country Planning Department. 1998. Area Development Plan (Final Draft). Bridgetown.
  • Barbados Water Authority. 1997. Draft Policy Framework for Water Resources Development and Management. Bridgetown.
  • Barbados Water Authority. 1997. Barbados Water Resources Development and Management. Statistical Services Department. Statistical Services Labor Force Survey. Bridgetown.
  • Statistical Services Department. 1994. Barbados 1990 Population and Housing Census, Vol I. Bridgetown.
  • Ministry of Agriculture. 1992. Barbados 1989 Agricultural Census. Bridgetown.



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