United Nations Office for Project Services (UNOPS) UNDP-Accra

Environmental Sensitivity Map for Coastal Areas of Ghana. Volume II - Coastal Environment

October 2004

Prepared for Environmental Protection Agency, Ghana by

United Nations Office for Project Services (UNOPS) UNDP-Accra

Environmental Sensitivity Map for Coastal Areas of Ghana. Volume II - Coastal Environment

October 2004

Prepared for Environmental Protection Agency, Ghana

Report no. Vol. II - Final Issue no. 1 Date of issue 30 October 2004

Prepared A.K. Armah, C. Biney S.Ø. Dahl and E. Povlsen Checked ERP/SDA/SHC Approved Steen Øgaard Dahl Environmental Sensitivity Map for Coastal Areas of Ghana 1

Table of Contents

1 INTRODUCTION 4

2 GEOGRAPHICAL BACKGROUND 5

3 PHYSICAL CONDITIONS 8

3.1 Climate 8 3.1.1 Rainfall 8 3.1.2 Evaporation 9 3.1.3 Temperature 9 3.1.4 Humidity 9 3.1.5 Wind 9

3.2 Hydrography 9 3.2.1 Temperature 9 3.2.2 Stratification of water masses (thermocline, halocline) 11 3.2.3 Tidal ranges 12 3.2.4 Salinity 12 3.2.5 Currents 12 3.2.6 Upwelling 13

3.3 Bathymetry and Sediments 14 3.3.1 The continental shelf and its extensions 14 3.3.2 Depth contours 15 3.3.3 Sediment types 16 3.3.4 Sediment balance 17 3.3.5 Littoral transport 17 3.3.6 Transport through tidal inlets 18

4 ECOLOGICAL CONDITIONS 19

4.1 Offshore Ecosystem 19 4.1.1 Introduction 19 4.1.2 Plankton 19 4.1.3 Fish 20 4.1.4 Shrimps and prawns 21 4.1.5 Shellfish grounds 21 4.1.6 Offshore benthic invertebrate fauna communities 21

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 2

4.2 Marine Coastal Ecosystems 22 4.2.1 Introduction 22 4.2.2 Sandy shores 23 4.2.3 Rocky shores 24 4.2.4 Coastal lagoons 26 4.2.5 Mangroves 31 4.2.6 Fringe forests 32 4.2.7 Estuarine wetlands 33 4.2.8 Depression wetlands 33

4.3 Birds 34 4.3.1 Songor Lagoon 35 4.3.2 Muni Lagoon 37 4.3.3 Sakumo Lagoon 37 4.3.4 Densu Flood Plain 39 4.3.5 Anlo-Keta Wetland 41

4.4 Endangered Species 43 4.4.1 Marine turtles 43 4.4.2 Manatees 44

4.5 Protected Areas 44

5 SOCIO-ECONOMIC CONDITIONS 50

5.1 Population and Settlements 50

5.2 Fishery 53 5.2.1 Introduction 53 5.2.2 Marine fisheries 54 5.2.3 Lagoon fisheries 60 5.2.4 Aquaculture 61

5.3 Oil and Gas Extraction 61

5.4 Salt Production 62

5.5 Industrial Development 63

5.6 Farming in Coastal Areas 63

5.7 Tourism 63

5.8 Historical Monuments 64

6 ENVIRONMENTAL DEGRADATION 67

6.1 Pollution 67 6.1.1 Municipal waste 67 6.1.2 Industrial waste 68 6.1.3 Chemical pollution from agriculture 68 6.1.4 Other chemical pollution 69

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 3

6.1.5 Oil spill events and threats 69

6.2 Coastal Erosion 70

6.3 Over fishing 71

6.4 Issues of Concerns in the Coastal Zone 72 6.4.1 Mangrove and wetland degradation 72 6.4.2 Sand and gravel mining in the coastal zone 72 6.4.3 Impact of inland drainage on coastal lands and waters 73 6.4.4 Endangered species 74

7 REFERENCES 75

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 4

1 Introduction Environmental Protection Agency of Ghana is the focal point for coastal zone management activities in Ghana and responsible for the National Oil Spill Con- tingency Plan. In order to strengthen the planning capabilities and support the Government of Ghana to perform sustainable coastal zone management, UNDP has supported the project ‘Environmental Sensitivity Map for the Coastal Area of Ghana’ with financial assistance from the Fund for Danish Consultancy Ser- vices administered by UNOPS.

The aim of the project has been i) to develop a GIS based environmental plan- ning tool for coastal zone management, ii) to develop a management tool for use in planning and implementation of oil spill response, and iii) to train the EPA staff in operating the GIS system

The project was carried out in 2003- 2004 by the joint venture of COWI and DDH Consulting both of Denmark with contributions from the national con- sultants, namely Charles Biney, A.K. Armah, Ernest Kusi-Minkah and George Botchie.

The project has been anchored in the Environmental Protection Agency with the assistance of the core staff of Daniel Amlalo, Roger Leh and Wilson Tamakloe.

The project has been reported in three volumes:

Volume I - Atlas. The Atlas contains 96 maps (scale1:20.000) covering the entire coastline of Ghana. The maps illustrate geological, ecological and human use features relevant in coastal zone management and in oil spill combat. Each map sheet includes a short description of the main features and indicates the ranking of the coastline in terms of sensitivity to oil spills

Volume II - Coastal Environment. The Coastal Environment Report de- scribes the geological-, hydrographical-, ecological- and socio-economical con- ditions mapped in the Atlas.

Volume III - Oil Spill Sensitivity Ranking. The Oil Spill Sensitivity Ranking Report describes the ranking system and the assessment of the sensitivity of the ecological and human use features to oil spill.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 5

2 Geographical background Ghana lies along the Gulf of Guinea in West Africa, within longitudes 3° 5’ W and 1° 10’ E and latitudes 4° 35’ N and 11°N. It covers an area of about 239,000 km2. The country is bordered by Togo to the East, Côte D’Ivoire to the West and Burkina Faso to the North.

The coastline of Ghana is about 550 km long.

Coastal plain Behind the coastline is a low lying coastal plain. The coastal plain is broad in the east and west, where it stretches over 80 km inland, and narrow in the mid- dle near Winneba and Accra. In this area it does not extend more than 16 km inland from the sea (Dickson & Benneh, 1980). There are two main vegetation zones on the coastal plain. In the Western part from the frontier with Côte d’Ivoire to Cape Coast the coastal plain is dominated by semi-deciduous and evergreen secondary tropical forest. The area from Cape Coast to the eastern border with the Republic of Togo comprises a relatively dry zone with low- lying thickets and savannah-grassland to the east (Armah and Amlalo, 1998).

Coastline and conti- Around 70 percent of the 550 km long coastline consists of sandy beaches. The nental shelf continental shelf (200 m depth limit) varies in width along the coast of Ghana, from 20 km off Cape St. Paul in the east to about 90 km at the expanded por- tion between Takoradi and Cape Coast in the west. Ghana’s offshore area (50- 200 meter depth) is estimated at 8,500 km2 and comprises soft (muddy and sandy-mud), hard and sandy bottoms. The coastal zone is dotted with over 90 coastal lagoons, most of which are very small and less than 5 km2 in surface area (Armah, 1993). The largest lagoon, the Keta Lagoon, however covers an approximate surface area of 350 km2 (Ababio, 2001).

The Ghanaian coastal zone may be divided into three geomorphologic zones (see Figure 2.1); the West, Central and East Coasts (Ly, 1980).

• The West Coast covers 95 km of stable shoreline and extends from Ghana's border with Côte d’Ivoire to the estuary of the Ankobra River. It is basically fine sand with gentle beaches backed by coastal lagoons.

• The Central Coast shoreline is 321 km long and extends from the estu- ary of the Ankobra River near Axim to Prampram, located to the east of Accra. It represents an embayed coast of rocky headlands, rocky shores and littoral sand barriers enclosing coastal lagoons.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 6

• The East Coast, which is made up of 149 km of shoreline, extends from Prampram eastwards to Aflao, at the border with Togo. It is character- ized by sandy beaches with the deltaic estuary of the Volta River situ- ated halfway in-between. The Volta River is the largest river in Ghana with a regulated flow of about 850 m3/s due to damming upstream. The East Coast has a significant proportion of its land area covered by the Keta Lagoon, the Volta Estuary and the Songor Lagoon.

Figure 2.1. Map showing the coastal zone of Ghana

Rivers The major rivers, which drain the coastal area, are, from the west, the Tano, Ankobra, Butre, Pra, Kakum, Amisa, Nakwa, Ayensu, Densu and Volta. Some of these such as the Amisa, Nakwa and Ayensu flow into the sea through la- goons. Three of these, the Ankobra, Pra and the Volta are among the largest and flow all year round. Peak discharges occur in June and July with low flows in February. For the Ankobra and Pra rivers, the mean discharge rates for the peak months are in the order of 110 and 480 m3/s respectively. The discharge rate for the low flow periods for the Ankobra River is about 4 m3/s and the Pra River 70 m3/s. The largest river in terms of catchment area and volume is the Volta, which was dammed in 1965 for hydroelectric power generation. It now has a regulated flow of approximately 900 m3/s. Tables 2.1 and 2.2 show the drainage areas and discharge of some of the major rivers.

Table 2.1 Drainage areas of main rivers

River Drainage Area (km2) Volta System 165,760 Tano 14,760 Ankobra 8,550 Pra 23,310 Other coastal rivers (Amisa, Nakwa, Ayensu and Densu) 19,420 Total 237,280

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 7

Table 2.2 Mean monthly discharge (m3/s) of Ghanaian rivers from 1967-1996 (Source: AESC-Hydro Division).

Month Volta Pra Ankobra Ayensu Amisa Nakwa Jan 778 94.2 5.0 5.0 2.8 2.8 Feb 825.3 70.8 3.9 2.8 1.9 1.4 Mar 839.0 94.2 21.2 4.0 2.8 3.9 Apr 846.7 117.8 49.6 5.0 5.0 5.0 May 867.7 117.0 70.8 7.1 5.0 5.0 Jun 897.0 460.0 117.8 28.3 28.3 24.8 Jul 895.3 495.6 106.0 21.2 24.8 21.2 Aug 879.3 279.0 28.3 14.2 5.0 7.1 Sep 850.0 247.8 49.6 24.2 10.6 14.2 Oct 828.7 424.8 94.2 14.2 14.2 10.6 Nov 858.7 318.6 318.6 7.1 7.1 10.6 Dec 850.0 117.0 10.6 5.0 5.0 5.0

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 8

3 Physical Conditions

3.1 Climate

3.1.1 Rainfall The climate of Ghana's coastal zone is tropical. The eastern coastal belt is warm and comparatively dry, the southwest corner hot and humid. It becomes pro- gressively drier from the southwest to the northeast of Accra. Two thirds of the coastal zone falls within the dry coastal savannah strip where annual rainfall ranges from 625 mm to 1000 mm and average 900 mm. Peak rainfall is in June and the lowest rainfall is observed in January. There is a double maxima annual distribution of rainfall in Ghana's coastal zone with the high maximum occur- ring in May/June and the low maximum in September/October. The lowest rainfall occurs in January. The relatively dry coastal climate of the southeast is believed to be caused by the prevailing winds (south-south-westerly) blowing almost parallel to the coast and to a cool current of water immediately offshore as a result of a local up-welling (Armah and Amlalo, 1998).

At the northern winter solstice, the doldrum zone lies to the south of the coast. The coastal areas are dominated by the NE Trade wind system, which is rela- tively free of clouds and rain, but is cool, dry, and dust-laden; it is known as the 'Harmattan'. Conversely, the SE Trade winds are associated with more clouds and precipitation, and divert in coastal regions above the equator as a southwest onshore monsoon. While there are two main seasons during the course of the year, the annual weather patterns are somewhat more complicated due to a short break in rainy season in August.

The typical weather is as follows:

• From April to July, there is a long rainy period (southern summer mon- soon season). The period starts with storms and humid SW winds of be- tween 15 m/s and 25 m/s. There is an up-welling event along the shore- line in July;

• A short dry period occurs in August as rainfall amounts suddenly de- cline about 75 percent;

• During October and November there is a short rainy period associated with decreasing winds and a weak up welling. Ocean surface tempera- tures increase during September, reaching 28°C; and

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 9

• From December to March there is a long dry season characterized by persistent Harmattan winds, which derive from anticyclone systems in the north.

3.1.2 Evaporation Mean annual evapo-transpiration ranges from a low of 1370 mm in Half Assini through 1490 mm at Cape Coast to 1674 mm along the East Coast.

3.1.3 Temperature The variation of temperature along the coast of Ghana is small. The mean daily maximum varies between 27oC – 29oC in August and 31oC – 33oC in Febru- ary/March. Mean annual temperatures range from 26oC in Half Assini to 28oC at Ada.

3.1.4 Humidity Relative humidity ranges between 50 - 80 percent in the eastern part of the coast and 70 - 100 percent in the west.

3.1.5 Wind The winds are characterized by persistent south-westerly monsoon modified by land and sea breezes in the coastal area. Speeds vary between 0.5 m/s at night and 2.0 m/s during the day. Storms are not common. Weaker line squalls with heavy rains and strong winds of short duration occur occasionally. Between December and February, hot dry north-easterly Harmattan winds occur when the inter-tropical convergence zone deviates from its southerly position be- tween 5oN – 7oN. The winds blow predominantly in a south-westerly direction with an average speed of 3 m/s throughout the year.

3.2 Hydrography

3.2.1 Temperature The temperature for the coastal waters ranges from about 16.3oC to about 28.8oC. Many deepwater sites exhibit numerous distinctly stratified thermo clines while shallow near shore sites demonstrate a distinct primary thermo cline with a linear temperature gradient to the bottom, indicating mixing of stratified layers already present. A strong density gradient in the euphotic zone, limiting the vertical exchange of nutrients between surface and deep waters is likely to exist. Surface temperatures of the photic zone are usually similar along the coast, on average 27.8°C. The Figures below show the monthly sea surface temperature distribution along the coastline.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 10

Figure 3.1. Monthly Sea Surface Temperature Distribution in the Coastal Waters of Ghana in 1997 (Source: Wiafe, 2002)

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 11

Figure 3.1.(continued)

3.2.2 Stratification of water masses (thermocline, halocline) Water masses offshore of the Ghanaian coast consist of five principal layers (Longhurst, 1962). A Tropical Surface Water (TSW, warm water of variable salinity) extends down to a maximum of about 45 m depending on the seasonal position of the thermocline. Below the thermocline (which varies from 5 to 35 m) occurs the South Atlantic Central Water (SACW, cool and high salinity wa- ter) down to a depth of about 700 m. Below this are consecutively, three cold

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 12

layers; the Antarctic Deep Water (ADW, 700-1500 m); the North Atlantic Deep Water (NADW, 1500-3500 m) and the Antarctic Bottom Water (ABW, 3500- 3800 m).

3.2.3 Tidal ranges The tide on the coast of Ghana is regular and semi-diurnal. The average range varies along the coast as shown in Table 3.1 for the main cities. As can be seen the tidal wave have virtually the same phase across the coast of the country. The average range of Neap and Spring tides increases from west to east. Tidal currents are low and have an insignificant influence on coastal processes except within tidal inlets.

Table 3.1. Tidal Range for the coast of Ghana

Location Tidal Range (m) Neap Mean Spring Phase Takoradi 0.58 0.90 1.22 107° Accra 0.62 0.94 1.26 107° Tema 0.64 0.96 1.28 107° Lome 0.68 1.00 1.32 108°

Other possible sources of intermittent increases of local water levels include line squalls and the transfer of energy from internal to surface tides. These processes could result in additional increases of about 30 cm.

3.2.4 Salinity o The salinity along the coastline ranges between 32 and 36 /oo. In coastal waters close to the major rivers, notably the Ankobra, Pra and the Volta, lower salinity o levels about 28 /oo may be recorded in the rainy season. For example, dry sea- o son measurement in December was as low as 31 /oo in Axim during the low tides due to the inflow of the Ankobra River 1km to the west of Axim. The Ankobra River has an annual mean flow rate of 51 m3/s (Armah and Am- lalo,1998). Salinity of the coastal waters generally increases from west to east as a result of higher rainfall in the west.

3.2.5 Currents The oceanography of the region is influenced by the meteorological and oceanographic processes of the South and North Atlantic Oceans, principally their oceanic gyro currents (Merle and Arnault, 1985; Fontaine et al., 1999).

The cold Canary and Benguela Currents are warmed as they flow towards the equator along the coastal margins. These currents then turn westward near the equator and diverge as the North and South Equatorial Currents (Longhurst, 1962). Between the North and South Equatorial Currents flows the Equatorial Counter Current (ECC). The ECC becomes known as the Guinea Current as it runs from Senegal to Nigeria. The Guinea Current flow the whole length of the

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 13

coast, as far as the Bight of Biafra, year round. It maintains its highest veloci- ties during the season of the southwesterly winds from June to October (Longhurst, 1962).

The ECC is driven by westward wind stress. When the wind subsides during February to April and October to November, it reverses (Garzoli and Katz, 1983; Richardson, 1984; Merle and Arnault, 1985). A small westward-flowing counter current lies beneath the Guinea Current. Below 40 m depth, it appears to turn to the southwest with velocities ranging from 0.5 to 1.0 m/s and 0.05 to 1.02 m/s near the bottom (Akpati, 1975; Binet et al., 1991). The cold subsur- face water could be a branch of the Benguela Current that penetrates and domi- nates the ECC.

3.2.6 Upwelling Upwelling seasons The coastal waters experience seasonal changes at the surface of the Tropical Surface Water (TSW). There is little change in the subsurface waters. The TSW layer is characterized by warm, well-mixed water that extends from the surface to the depth of the thermocline (about 30 m – 40 m). Seasonal changes in the hydrographic regime occur in the form of minor and major upwelling events, alternating with periods of stratification. Between January and February, the surface waters tend to be slightly cooler, indicating a minor upwelling.

By the end of June, there is an increase in the easterly wind in the western equatorial Atlantic that brings up cold South Atlantic Central Water (SACW) to replace the TSW (Moor et al., 1978). When the thermocline breaks, it signals the onset of the major upwelling. The sea surface temperature can fall from 30oC in May to 18oC in August. The subsurface system appears to comprise all the principal water masses of the South Atlantic.

Zone of upwelling The zone of upwelling extends from Cote d’Ivoire to Benin. Monitoring of beach temperature reveals that upwelling intensity is greater in the vicinity of Takoradi where the temperatures are usually lower than elsewhere in Ghanaian waters.

The cause of the upwelling has been the subject of research and debate by many scientists. Unfortunately, there has not been any acceptable explanation for the mechanism of this upwelling, as it does not follow any of the classical types.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 14

Figure 3.2. Upwelling areas along the west coast of Africa

3.3 Bathymetry and Sediments

3.3.1 The continental shelf and its extensions The continental shelf varies in width from a minimum of about 20 km off Cape St. Paul to about 90 km at the widest portion between Takoradi and Cape Coast. Submarine canyons exist off the Volta Delta (Edwards et al., 1997). A belt of dead madreporarian coral beginning at 75 m seaward traverses the entire shelf. Beyond this coral belt, the bottom falls sharply, marking the transition from the continental shelf to the slope. Soft sediments predominate along the coastline up to the coral belt.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 15

Figure 3.3. Marine Environment of Ghana Showing Configuration of the Coastline and Bathymetry (Source: Armah and Amlalo, 1998)

The shelf has been considered seismically stable, but recent tremors suggest the presence of some crustal instability. An active faulting has been identified near the intersection of the east-west coastal boundary fault zone and the northeast to southeast Akwapim fault zone (Tsidi et al. 1995). Currents along the coast- line move sands from west to east, forming a barrier beach system. This littoral drift is interrupted at a few places by the construction of harbours and groynes built to reduce shoreline erosion.

3.3.2 Depth contours The nature of the topography of the Ghanaian continental shelf is generally known but detailed studies which could lead to the production of coastal charts (1:50,000) showing sediment, intrawlable grounds and other features have not been made. The approximate surface areas of sedimentological subdivisions are shown in Table 3.2.

Table 3.2. Approximate surface areas of offshore sedimentological subdivi- sions

Zone Substrate Area (km2) INSHORE (10-50 m) Soft (muddy to sandy mud) 8,700 Hard and sandy 2,700 Rocky and non trawlable 300 SUB-TOTAL 11,700 OFFSHORE (50-200 m) Soft 6,500 Hard and sandy 2,000 SUB-TOTAL 8,500 TOTAL 20,200

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 16

3.3.3 Sediment types Sandy beaches constitute about 70 % of the coastline. The sediment along the coastline are redistributed mainly by a primarily eastward longshore current, in the form of littoral drifts and less importantly, tidal currents. There are several coastal streams and lagoons along the coastline that deposit sediment into the marine environment. The amount of sediment transported is closely related to levels of river discharge into the sea (Mensah, 1991). The latter is a factor of the amount of rainfall during the rainy season. It has been estimated that the two major rivers in the country (Volta and Pra) transport a total of 17.9x106 tons of sediment per year into the sea.

The sediment ranges from coarse sand particles in the inner shelf to fine sand to dark grey mud in the outer shelf. The mean sediment size ranges from 0.29 to 2.00 phi1.The sediment types that dominate the offshore region contain more than 75% terriginous grains lying on most parts of the shelf and upper slope, detrital sands with an admixture of carbonate on most of the outer shelf and up- per slope and glauconite-rich sediment with mixtures of biogenic carbonate in the outer part of the shelf and upper slope. The carbonate-rich sediment found on the outer shelf and upper slope off Cape Three Points is mainly silty mud, composed primarily of molluscan debris. From the inshore waters (~10 m) down to 200 m depth of the continental shelf margin, the surface coverage of the ocean bottom consists of 75% muddy to sandy mud, 23% hard and sandy sediment and 2% rocky type layer (Berncsek 1986; Armah & Amlalo, 1998).

The mean grain size and sorting coefficient (as error bars) along the coast of Ghana is presented in the Figure 3.4 below. The graph shows a gradual increase in average grain size from the west coast to the east coast (trendline).

5.0

4.0

3.0 e l a c 2.0 i S

Ph 1.0

0.0

-1.0 i i t e a n i h d s d m a u r a a a u n in m im h c da a n b k o am ga n w s kw a x w c ra o a e a n r ingo et o A o te ea en tp n r ia p N any Ad lo K De lf A Ei si T n ko m Co l Ap in e rt m b a s B o e B o a d a An w T E ss ke Ta K p Sa W a B pl H e A ua y Pr Ol k Ne ic s Ca A Pr Bu Sen Towns (Stations)

Figure 3.4. Mean grain size (phi scale) of sediments from principal locations along the coast showing general increase of grain size from west to east.( Armah, 2003, unpublished).

1 The phi scale is defined as -log2(grain size diameter) and is a commonly used term for grain size. Examples are: phi=0 equals grain size diameter 1 mm; phi=2 equals grain size diameter 0.25 mm; phi=-2 equals grain size diameter 4 mm

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 17

3.3.4 Sediment balance The main sources of sediment to the littoral zone are from rivers and erosion of shores and cliffs. The Ankobra, Pra and Volta River are the main sources of fluvial sediment supply to the coast. From these sources, the sediment is re- distributed by the incessant action of waves, currents and to a lesser extent the influence of tides. In general, sediment is transported both by longshore trans- port (i.e. parallel to the shoreline) and onshore transport (i.e. perpendicular to the shoreline).

It is estimated that the sediment yields of rivers along the coast varies between 30 – 80 tonnes/km2 per annum depending on the area of the catchment, topog- raphy, geology and climate of the coastal area (EC, 1989).

3.3.5 Littoral transport The action of the waves result in the transport of sediments put into suspension and transported by wave-induced currents along the shores. The rate of trans- port depends on the energy of the waves, the period of the waves and the direc- tion of the waves. The wave characteristics as well as the particle size charac- teristics of the sediments determine the amount of material that can potentially be transported along the shores.

The orientation of the West Coast is such as to expect some transport when the wave direction is south which an occurrence that predominates throughout the year but associated with low energy waves. When the wave direction changes to SSW or N 210° E, the angle the waves make with the coast is reduced to a negligible value. The little transport associated with the South waves may just be sufficient to distribute sediment from the Ankobra River. The beaches in this area are thus stable.

An estimate of the transport capacities of the Central Coast gives a littoral transport capacity of 400,000 m3/yr for the West Central Coast and 800,000 m3/yr for the East Central Coast. The transport amounts indicate an increasing transport potential from West to East. Available supply of sand from the rivers and shores is of the order of 200,000 m3/yr. The low value of the supply of sediment as compared with the transport capacity results in erosion and the ex- posure of the rocky substratum on the beaches.

On the East Coast, the Ministry of Works and Housing (1997), has estimated that the transport reduces from 1 million m3/yr along the straight shorelines running West to East to 50,000 m3/yr at Dzelukope and then increases to 215,000 m3/yr near Blekusu.

Sediment supply for this littoral zone has been from the River Volta, which dis- charged about 1 million m3/yr prior to the construction of the dam at Akosombo and to a lesser extent from erosion of the beaches. Generally, the shoreline south of the Volta Delta runs virtually straight in west to east direction. Follow- ing the damming of the Volta River cutting off substantial amounts of sedi- ments that reach the littoral zone, erosion has become of critical concern aver- aging about 2 - 3 m/year in recent times The only shorelines of the East Coast that are stable or accreting are the shores in the east from Aflao to Blekusu and

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 18

then from Dzelukope to Anloga. The bulging of the shoreline forming Cape Saint Paul has been shaped by the action of the waves and the sediment coming from the Volta River. The existence of the sandy Cape Saint Paul has contrib- uted to shoreline recession in the Keta area (Anthonio, 1993). Ly (1980) esti- mated the recession in the Keta area to have increased from 4 m/year before the construction of the dam on the Volta River in 1965 to 8 m/year after the dam construction. The rate of erosion in the Keta area is the worst that Ghana has ever experienced. Episodes of shore erosion over the last several decades have caused losses, perhaps as much as 70 percent, of the original residences and buildings in the towns and the coastal road between Keta and Havedzi. Coastal defence works aimed at protecting the Keta area from further erosion as well as flooding from the Keta lagoon were initiated in 2000 and completed in early 2004. This has effectively stopped the erosion at Keta and reclaimed land for rehabilitation. The entire defence works comprised four principal components:

1) Sea defence (construction of one 800m long revetment, seven groy- nes, up to 250m long each, and beach nourishment); 2) Land reclamation (using an estimated 4,220,000m3 of sand); 3) Construction of a +/- 8 km road link between Keta and Havedzi; and 4) Construction of a flood relief structure (to relieve flooding events on communities around the lagoon).

3.3.6 Transport through tidal inlets Estuaries and lagoons on the coast may be opened to the ocean or closed by a sand bar. The channel that is created when the estuary/lagoon is connected to the ocean is known as a tidal inlet. Through tidal inlets, sediment may be trans- ported to the littoral zone from rivers and the coastal plains in times of floods during or after the rainy season. During low flows the net transport of sediment could be into the lagoon/estuary raising the bottom elevation of the la- goon/estuary.

The main factor, apart from the river discharges during floods, influencing the transport of sediment through an inlet is its tidal prism which together with the net littoral transport across the mouth of the inlet determines if the inlet would remain opened or closed to the ocean (Bruun, 1962). On the coast of Ghana, open lagoons/estuaries tend to occur along the western sections of the Central Coast where rainfall is high. Closed lagoons tend to occur on the eastern parts.

There are about 26 permanently open lagoons while 13 lagoons are open in part of the year - usually in periods with major run-off from the catchment area (designated as ‘semi-closed’ lagoons).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 19

4 Ecological Conditions In this section the ecological conditions along the coast of Ghana are described in terms of:

1) The offshore ecosystems, i.e. the ecosystems encountered off the shoreline on and above the Continental shelf

2) The marine coastal ecosystems, i.e. the ecosystems found on the coastline and in the immediate near shore areas

4.1 Offshore Ecosystem

4.1.1 Introduction The seasonal upwellings that take place in the Gulf of Guinea each year from June to late September (major upwelling) and in December-January (minor upwelling) are of fundamental significance for the offshore ecosystem along the coast of Ghana. The upwellings bring cold, nutrient rich water to the sur- face. The nutrients cause blooms of plankton, attracting large shoals of small pelagic fish species, which form the basis for large seasonal fisheries along the coast.

4.1.2 Plankton The primary production in the Gulf of Guinea is high (>300 gC/m2-yr) with a peak production from June to September. The zooplankton biomass peaks very soon after the phytoplankton blooms.

During the upwelling periods the phytoplankton is dominated by diatoms such as Leptocylindrus sp, Nitzchia sp., Chaetoceros sp. and Rhizosolenia sp and Skeletonema costatum. During the periods when upwelling does not occur dinoflagellates are dominant

The zooplankton is completely dominated by Copepods (85-95%) with Ca- lanoides carinatus as a common species (Marine Fisheries Research Division 1995; Marine Fisheries Research Division, 2003).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 20

4.1.3 Fish Pelagic species The dominating pelagic fish stocks, which are sustained by the upwelling, are:

• Round sardinella (Sardinella aurita)

• Flat sardinella (Sardinella maderensis)

• Chub mackerel (Scomber japonicus) and

• Anchovy (Engraulis encrasicolus),

Round Sardinella The Round Sardinella (Sardinella aurita) schools in the coastal waters from inshore to the edge of the continental shelf. It is a migratory species, often ris- ing to the surface at night and dispersing. It feeds mainly on zooplankton, espe- cially copepods. The spawning seasons of the round sardinella coincides with the periods of coastal upwelling. Spawning take place in March, but the most significant spawning period is between July and October with peak spawning in August (Marine Fisheries Research Division, 2003). Eggs and larvae are pe- lagic and are transported by the currents. Juveniles tend to stay in nursery areas, but on maturity rejoin adult stocks offshore. Juveniles feed on phytoplankton.

Flat Sardinella The Flat Sardinella (Sardinella maderensis) also forms schools in coastal wa- ters. They feed on a variety of small planktonic invertebrates, fish larvae and phytoplankton. The flat sardinella spawns in July-September.

Figure 4.1. Flat sardinella (Sardinella maderensis).

Anchovy The Anchovy (Engraulis encrasicolus) also form large schools in coastal ma- rine waters. They may also enter lagoons and estuaries, especially during the spawning season, which is from April to November. The eggs are pelagic float- ing in the upper 50 m.

Chub Mackerel The Chub Mackerel (Scomber japonicus) form schools by size. It initiates schooling at a size of approximately 3 cm. The Chub Mackerel stays near the bottom during the day but migrate to the surface water at night, where it feeds on copepods and other crustaceans, fishes and squids.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 21

Tunas The small pelagic species are hunted by large pelagic species such as Yellowfin tuna (Thunnus albacares), Bigeye tuna (Thunnus obsesus) and Skipjack tuna (Katsuwonus pelamis).

Demersal species The offshore ecosystem also includes a wide variety of demersal (bottom- living) species. The major demersal species of importance for the fisheries in- clude the families Sparidae (redfishes), Pomadasidae (burros), Scaenidae (croakers), Lutjanidae (snappers), Mullidae (goatfish), Serranidae (groupers) and Polynemidae (threadfins) (Marine Fisheries Research Division, 2003).

4.1.4 Shrimps and prawns The most common species of marine shrimps in Ghana are the penaeid species Penaeus notialis and Penaeus setiferus. These species migrate from inshore waters to offshore areas to spawn. The migration is triggered by a decrease of salinity resulting from the freshwater run-offs during peak rainy periods in June and September.

The original shrimp trawling grounds in Ghana were coastal waters off Cape Three Points, Cape St. Paul at Keta and Accra. However, in recent years more shrimping grounds have been identified in the coastal waters off Shama, Adjoa, Axim, and Half Assini off the west coast of Ghana; and Ada off the east coast of Ghana. The estimated total area of the main shrimp grounds in Ghanaian wa- ters is approximately 520 km2 within water depths of 24 m to 45 m (Jones, 1970).

4.1.5 Shellfish grounds Recently large quantities of scallops (Chlamys purpuratus and Pecten Jaco- beus) have been discovered in the offshore areas extending from Winneba to Sekondi. Their distribution is however patchy. They are found within the water depths of 26 m and 27 m at the positions 40 59.77´ N; 1o 09.45´ W and 4o 59.76´N;1o 08.03´ W. These areas may require designation as marine protected areas to safeguard these bivalves, which are sensitive to disturbance by trawl- ers.

4.1.6 Offshore benthic invertebrate fauna communities The offshore benthic invertebrate fauna were described by Buchanan (1957, 1958). The following groups of fauna were identified: polychaete worms, rib- bon worms, amphipods, bivalves, gastropods, and decapod crustaceans. A re- cent study identified 359 taxa comprising 255 polychaete species, 49 crustacean species, 36 molluscan species, and 19 species of echinoderms, oligochaetes and sipunculids in the offshore environment. The abundance and distribution of these species followed seasonal climatic changes. Polychaetes were completely dominating (71 %). Crustacean and mollusc species contributed 14 % and 10 % respectively and other groups accounted for 5 % (i.e. echinoderms, oligochaetes and sipunculids).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 22

Polychaetes and crustacean species have been recorded to increase in abun- dance with water depths whilst echinoderms, oligochaetes and sipunculid de- crease in abundance with water depths. This pattern could be attributed to local factors.

Figure 4.2. Scallops caught in the offshore areas extending from Winneba to Sekondi.

4.2 Marine Coastal Ecosystems

4.2.1 Introduction There are six major types of ecosystems along the shores of Ghana, i.e.

• Sandy marine shore ecosystems

• Rocky marine shore ecosystems

• Coastal lagoon ecosystems

• Mangrove/Tidal Forest ecosystems

• Estuarine wetland ecosystems

• Depression wetland ecosystems

Table 4.1 give some examples of locations of these ecosystems

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 23

Table 4.1. Marine coastal ecosystems encountered along the coast of Ghana.

Marine Coastal Ecosystems Locations/examples

Sandy Marine Shores Cote d’Ivoire border to Axim, Prampram to the bor- der town of Aflao. A total of 385 km shoreline Rocky Marine Shores Senya Bereku, Cape Three Points Coastal Lagoons a) Open lagoon: Korle b) Closed or semi-closed lagoon: Songor, Muni Mangrove/Tidal Forest Lower reaches of Volta, Oyibi, Kakum, Ankobra Estuarine Wetlands Mouths of Volta, Pra, Butre, Ankobra Depression Wetlands Belibangara, Ndumakaka, Efasu

4.2.2 Sandy shores Sandy shores are the most prominent coast type in Ghana. As much as 385 km of the 550 km long coastline is made up of sandy shores. Long stretches of sandy beaches occur from the Cote d’Ivoire border to Axim and from Pram- pram to Aflao at the border to Togo.

Fauna Species diversity on sandy beaches is rather low, especially on beaches with coarse sand and steep slope. On such beaches only one species is normally en- countered, the ghost crab (Ocypoda cursa). This crab is active when the tide is low and retires to its burrow on the beach when the tide rises.

The species diversity is higher on fine grained flat sandy beaches with the fol- lowing species normally occurring: Ghost crab (Ocypoda cursa), the isopod Excirolana latipes, the amphipods Urothoe grimaldi and Pontharpinia inter- media, the mysid Gastrosaccus spinifer, mole crab (Hippa cubensi), the poly- chates Narine cirratulus, Glycera convoluta and Lumbrinereis impatiens, the bivalve Donax pulchellus and the gastropods Terebra micans and Olivancil- laria hiatula (Gauld & Buchanan, 1956).

Additionally, some segments of sandy beaches serve as important nesting sites for sea turtles (cf. Section 4.4).

Strand vegetation Above the high tide mark, typical strand vegetation is encountered. Typical species of this strand vegetation are the creepers Canavalia rosea and Ipomea pes-caprae in association with the grasses Cyperus maritimus and Diodia vaginalis. Prickly pear cactus (Opuntia vulgaris) is occasionally found

Further inland on the sand dunes, the vegetation may include the dwarf palm, Phoenix reclinata and the shrubs Baphia nitida, Grewia spp, Sophora occiden- talis, Thespesia populnea and Triumfetta rhombaidea. Coconut palms are also very common along the sandy shores (Taylor, 1960; Boghey 1957).

Benthic fauna The benthic fauna on the shallow water off sandy beaches consists of polychaetes, arthropods, molluscs, bryozoans and echinoderms (Bassindale 1961; Buchanan, 1957; and Evans et al. 1993). Edmunds (1978) recorded 68 taxonomic families of mollusc.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 24

Fish A number of fish species are typically found in shallow sandy seabed areas including the sergeant major fish (Abudefduf saxatilis), soles and tongue soles. Pelagic species such as mackerel and sardinellas also frequents coastal waters (Irvin, 1947).

4.2.3 Rocky shores Rocky shores are located mainly between Axim and Prampram where they oc- cur as rocky out-cropping alternating with sandy bays (Lawson, 1956).

The rocks are substrate for a wide variety of species of macroalgae, barnacles and littorinid snails.

Algae Ecologically, algae mats on rocky shores serve as important micro-habitats for epifauna (i.e. crustacean, macro-invertebrates) and fish.

The distribution of algal species on rocky shore in Ghana extends discontinu- ously from Prampram in the eastern coast to Axim near the Ankobra River on the western coast. Dominating species of macroalgae include: Sargassum vul- gare, Dictyopteris delicatula, Ulva fasciata, Chaetomorpha sp.and Lithotham- nia sp.(Lawson, 1956).

Figure 4.3. Algae on rocky outcrops during low tide at Prampram.

Fauna The rocks are also substrate for barnacles (Chthamalus dentata, Balanus tintinnabulum), snails and limpets. The common snails are the Littorina punc- tata. Other snails often encountered include Nodilittorina meleagris, Nerita senegalensis and the whelk Thais haemastoma. The dominating limpets are Si- phonaria pectinata, Fissurella nubecula and Patella safiana. At some sites oys- ters (Ostrea sp.) are found among the barnacles (Lawson, 1956).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 25

A number of fish species are characteristic of rocky seabeds. These include rainbow wrasses (Coris julis), parrot wrasse (Callyodon), morays and scorpion- fishes.

Zonation The distribution of algae, barnacles and snails is influenced by physical, chemical and biological factors. There is a typical zonation of species from the coastline seawards depending on depth and exposure to wave action (cf. Table 4.2) (John, 1987).

Table 4.2. Natural rocky shore zonation in Ghana with associated flora and fauna. After John (1986).

A B C D Relative Exposed Moderately Moderately Sheltered shore exposed sheltered height (m) Littorinids (snails) +1.60

Barnacles Littorinids

Brown algae Barnacles Littorinids

Blue-green Littorinids +0.80 Barnacles Chaetomorpha Ralfsia sp. Bachelotia sp. Barnacles spp. Enteromorpha Bachelotia sp. sp. 0.00 Red algal ‘turf’ Red algal ‘turf’ (mean sea Lithothamnia Lithothamnia Lithothamnia level) Small ‘mats’ of Red algal ‘turf’ red algae Dictyopteris sp. Lithothamnia Sargassum sp. Sargassum sp. -0.40 Lithothamnia Dictyopteris sp. Sargassum sp. Dictyopteris sp. -0.80 Lithothamnia

Flora and fauna in Tide pools are stagnant water in hollows and depressions of rocks established at tide pools in rocky low tide. Tide pools may also form above the zone not normally influenced by areas the tide. The water in such pools is replenished by wave spray, wave splash or by rainwater.

The tide pools house a quite rich vegetation of algae and a diverse fauna of in- vertebrates and fish. Due to the constantly changing temperature, salinity and oxygen concentrations in the tide pools only hardy organisms well adapted to the changing conditions are encountered.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 26

Examples of algae, which may be found in tidal pools, include: Sargassum vul- gare, Dictyopteris delicatula, Dictyota spp., Padina durvillei and Galaxaura marginata. Tide pools in the supra-littoral zone are usually free from sand and are lined by Lithothamnia sp. and Ralfsia expansa.

The fauna encountered in tidal pools include crabs and sea urchins such as Echinometra lucunter. The fauna in the tide pools also include the damselfish Microspathodon frontatus, Rupescartes atlanticus and juveniles of Abdefduf hamyi, the sergeant major fish (Abdefduf saxatilis) and the parrot-fish Pseudo- scarus hoefler.

4.2.4 Coastal lagoons Coastal lagoons are an important feature of the coastline of Ghana. There are more than 90 lagoons along the entire coastline. Coastal lagoons are bodies of salt water (from brackish to hypersaline), which are separated from the sea by barriers of sand and run parallel to the shore. They are important and vulnerable ecosystems, housing a wide variety of fish, shrimps, crabs, mollusc and poly- chaete species. They may be nursery areas for juveniles of marine fish and shrimp. Some lagoons are wintering sites for Palaearctic birds as well as roost- ing sites for local waterfowls. Five of the lagoons are designated Ramsar sites namely the Sakumo, Densu, Muni-Pomadze, Keta and Songor.

Two kinds of coastal lagoons are encountered in Ghana; these are ‘open’ and ‘closed’ lagoons.

Open lagoons The open lagoons have a permanent opening to the sea, they are normally fed by rivers that flow all year round and may form an extensive branched estuarine system of marshlands. There are about 26 open lagoons along the coast. Most of the open lagoons occur on the central and western parts of the coastline where higher rainfall results in a more continuous flow of the rivers and streams that run into them. Some lagoons that have previously been closed have been permanently opened to the sea in a bid to forestall seasonal floods from breaking the sandbar on which may be located an important facility e.g. the beach road on the Sakumo Lagoon near the port town of Tema.

Closed lagoons The closed lagoons typically lie behind a sand barrier, which separates them from the sea. They are more common on the eastern segments of the coast where rainfall is low and highly seasonal. In the rainy season, some of the closed lagoons do open to the sea as a result of floodwaters breaching the sand barrier. This occurs mainly as a result of freshwater seepage through the sand- bar, which makes it more susceptible to erosion by the sea (Kwei, 1977). Storm surges may also erode sandbars and open up closed lagoons to the sea (Armah, 1991). Under other circumstances, the sandbar may be manually breached dur- ing the rainy season to reduce the risk of flooding where this is considered a threat. About 13 lagoons can be characterised as ‘semi-closed’ lagoons.

The coastal lagoons are fringed by intertidal mud-or sandflats and in some sites by mangrove swamps.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 27

Physico-chemistry The temperature and oxygen levels fluctuate greatly within closed lagoons and they undergo sharp salinity changes ranging from near fresh water level during the rainy season to levels greater than 80‰ in the dry season (Kwei, 1977).

In open lagoons on the other hand conditions are buffered and changes in salin- ity, temperature and oxygen concentrations are moderate, because the water maintains some continuity with the sea for most part of the year.

The difference in salinity, temperature, oxygen levels and connections to the sea causes marked differences in the ecology and biodiversity of open and closed lagoons. This difference is evident when comparing data from Muni La- goon and Sakumo II Lagoon. Muni Lagoon is a closed lagoon that only occa- sionally is opened to the sea and Sakumo II is permanently connected to the sea via culverts (Table 4.3). The species compositions in the two lagoons are typi- cal for the fauna one generally encounters in open and closed lagoons.

Ecology of closed The species diversity in closed lagoons is low. The closed Muni Lagoon had lagoons only 3 species of fish and 9 species of invertebrates in May-June 1994.

The low species diversity in closed lagoons is due to highly variable salinity and the fact that during dry periods the salinity may be much higher than in the sea. Not many species can tolerate this.

In closed lagoons the Tilapia Sarotherodon melanotheron is usually the domi- nant fish species present (Pauly, 1976). It has acclimatised itself to the fre- quently hypersaline conditions occurring here and the reduced variety of food present. This type of lagoon is not open to the sea or only open for short periods of the year. Thus migration of fish and crustaceans from the sea is minimised and species from freshwater may find the lagoon too saline during dry season, which also contributes to the low species diversity.

Ecology of open la- The species diversity in the open lagoons is much higher than in the closed la- goons goon. In Sakumo II (the Densu Flood-plain) 14 species of invertebrates and 13 species of fish were caught in May-June 1994 (Table 4.3). The fish species in- clude true lagoon species, freshwater species that migrate from the rivers espe- cially during the rainy season and marine species migrating from the sea into the lagoons.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 28

Table 4.3. Comparison of salinity and diversity of invertebrates and fish of Muni Lagoon and Sakumo II Lagoon. Investigations carried out in March- June 1994 (source: Koranteng 1995a; Koranteng 1995b).

Muni Sakumo (II) Lagoon type Closed lagoon Open lagoon (Opens to the sea occasionally dur- (Permanently connected to the ing rainy season) sea via culverts) Hydrography Very variable salinity and hyper- Salinity decreased from 15-20 o o saline conditions during dry season. /oo in May to 2 /oo in June o Sharp decrease from 63 /oo in April o to about 20 /oo in May. Invertebrates 6 species of invertebrates 14 species of invertebrates Crustaceans: Crabs Uca tangerii Uca tangerii Callinectes latimanus Callinectes latimanus Cardiosoma armatum Cardiosoms armatum Molluscs: Sesarmia africana Tympanotonus fuscatus Shrimps Macoma cumana Parapenenaeopsis atlantica Turitella meta (juvenile) Penaeus duorarum (juvenile) Molluscs: Tympanotonus fuscatus Macoma cumana Semifusis morio Turritella ungulina Turitella meta Tivela tripla Anadara senilis Crassostrea tulipa Fish 3 species of fish 13 species of fish Sarotherodon melanotheron Brackish water species Tilapia zillii Sarotherodon melanotheron Liza falcipinnis Tilapis zillii Gobius ansorgii Periothalmus spp Freshwater species Oreochromis niloticus Clarias anguillaris Hemichromis bimaculatus Marine visitors Gerres melanopterus Lethrinusatlanticus Lutjanus fulgens Albula vulpes Juvenile forms Liza falcipinnis Mugil sp.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 29

Pauly (1975) defined four groups of fish and shrimps encountered in open coastal lagoons:

• Freshwater fish which swim into the lagoon during the rainy season (in- cluding the species Clarias anguillaris, Hemichromis bimaculatus, Oreochromis niloticus and Tilapia zillii.

• Fish species that spend all or most of their lives in the lagoon including the tilapia species Sarotherodon melanotheron, the mudskipper Priop- thalmus kaelruti and different species of gobids.

• Marine fish species that come into the lagoon for short incursions, such as Albula vulpes, Lutjanus fulgens and Lethrinus sp.

• Those that spawn at sea but have their juvenile forms washed into the lagoon just after the rainy season. The species use the lagoons as nurs- ery grounds, where they feed. Examples of species are the fish Mugil sp and Gerres melanopterus and the shrimp species Penaeus duorarum and Parapenaeopsis atlantica.

The mangroves and the bird life in the lagoons are described sections 4.2.5 and 4.3, respectively. Detailed descriptions of the flora and fauna of individual la- goons are found in the Atlas.

Figure 4.4. Tilapia Black-chinned tilapia (Sarotherodon melanotheron), which is very common in lagoons along the coast of Ghana

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 30

Table 4.4. List of selected coastal wetlands, approximate sizes and uses/benefits. WH = wildlife habitat; SP = salt production; F = Fishing (Source: Armah, 1993b).

Name Size (km2) Uses Benefits Amunsure (Nzulezo) 50.0 WH, F Aladoa 1.3 WH,F Anankwari 3.7 WH,F Abrobeano 1.7 WH, F, SP Fosu 1.0 WH, F Apabaka 1.5 WH,F,SP Muni 2.7 WH, F, SP Oyibi 3.6 WH, F, SP Sakumo 14.0 WH, F Korle 1.0 WH, F Kpeshie 1.6 WH, F Laloi (Laiwi) 10.2 WH, F, SP Gyankai (Djange) 3.5 WH, F, SP Songaw 15.0 WH, F, SP

Mixed extensive patches of Ruppia maritima and Ruppia – Sesuvium associa- tions were recorded in the Keta Lagoon, located at 6003’N and 0053’E. These remain the dominant and most important vegetation type in the lagoon. The dis- tribution of this submerged aquatic vegetation differs markedly between the dry and wet seasons. In recent time, local conditions have drastically affected the survival of this submerged aquatic vegetation.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 31

Figure 4.5. Vegetation in and around Keta Lagoon, including Ruppia maitima (Annual Report, 2000 on Environmental Monitoring Studies on Keta Sea Defence Works by RPI & ESL).

4.2.5 Mangroves The occurrence of Mangrove along the coast of Ghana is sparse. In 1995, the total area of land occupied by mangroves was estimated to be around 10,000 ha (Saenager and Bellan, 1995). Today, the area is probably significantly smaller.

Most of the mangroves are associated with lagoons and river deltas and are at various levels of degradation primarily through over-cutting and conversion to salt pans. In several places only scattered clumps of mangroves remain. Today good stands of mangroves are limited to three main areas:

• Around Elmina in the Western Region

• Near Iture, west of Cape Coast in the Central Region, and

• At the Volta Delta.

Species of mangrove Five species of mangroves are found in Ghana, which are the red mangroves, Rhizophora racemosa, Rhizophora mangle and Rhizophora harrisonii and the white mangroves Avicennia germinans and Laguncularia racemosa.

The red mangroves are the primary colonists in the open lagoon systems, which have regular tidal exchange whereas the white mangroves are the primary colo-

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 32

nists in closed lagoons (Sackey et. al., 1993). One of the obvious exceptions to this is the Korle Lagoon in Accra, which is an open type but colonized exclu- sively by the white mangrove Avicennia germinans.

Besides the lagoons, mangroves occur in the Volta Delta and the flood plains of the Kakum River at Iture. The best stands of mangroves in Ghana are found at the Volta Delta where the most common species is Rhizophora racemosa. The highest species diversity of mangroves in Ghana occurs at the Iture stand. Here, five species of true mangroves occur, i.e., Rhizophora racemosa, Rhizophora harrisonii, Rhizophora mangle, Avicennia germinans and Languncularia ra- cemosa. Other associated vegetation include: Conocarpus erectus, Thespesia populnea, Acrostichum aureum, Phoenix reclinata, Sessuvium portulacrastrum and Phylloxerus vermicularis.

Other plant species In the drier areas of the mangrove habitats, where less saline or normal soils in mangroves occur, other species such as Dahlbergia escastophyllum, Drepanocarpus luna- tus, Hibiscus tiliaceous and Terminalia catappa may be found.

Fauna in Mangroves In the mangroves, an abundance of oysters, gastropods, crabs (such as Sesarma sp.and Uca sp) and invertebrate larvae feed on the enormous deposits of or- ganic matter provided by mangrove trees and the large amount of sediments trapped by the mangrove roots. Mangroves in open lagoons and river deltas are important as nursery and feeding areas for marine fish and shrimps. Birds such as herons and cormorants raise their young in mangroves.

Figure 4.6. Fiddler crab (Uca sp) is common in mangrove areas

4.2.6 Fringe forests Fringe forests are encountered between 4° 46’ and 4° 48’ N and 2° 05’ and 2° 09’ W. Along this stretch of the coast the rain forest fringe the Ehunli and Ak- puhu Lagoons and an estuary where the rivers Nyile and Kpani meet along the western coastline. The Cape Three Point Forest Reserve occurs in this area as

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 33

well. A total of 141 species belonging to 58 diverse plant families made up of trees, shrubs, herbs, grasses and sedges have been observed in this area (RC, 2000).

4.2.7 Estuarine wetlands Estuarine wetlands comprise all wetland areas, which are exposed when the tide is out as well as the plains of estuaries, which are seasonally inundated dur- ing the rainy season. Again, the Volta River estuary wetland is the most promi- nent although due to the construction of two large dams upstream, seasonal flooding of the plains have been significantly reduced, altering the natural char- acteristics of this extensive wetland. Extensive stands of mangrove and other species typical of swamp forests still exist. Other floodplain wetlands occur in the west of the country where rainfall is high.

Estuarine fishes include the tarpon (Megalops), the shad (Ethmalosa frimbri- ata), the long finned herring (Ilisha africana), the ten-pounder (Elops lacerta), the barracuda (Sphyraena sphyraena), the flatfish Citarichthys stampflii, the tongue sole (Cynoglossus senegalensis), the pompano (Trachinotus gorensis), drums (Pseudotolithus elongatus, Pseudotolithus epipercus), the burro fish (Pomadasys jubelini and Pomadasys peroteti) as well as the burrito (Brachy- deuterus auritus) and the threadfin (Pentanemus quinquarius) (Schneider, 1990)

Table 4.5. List of selected of Estuarine Wetlands (associated with large wa- tercourses) approximate sizes and uses/benefits. WH = wildlife habitat; SP = salt production; F = Fishing (Source: Armah, 1993b).

Name Size (km2) Uses Benefits Butre 3.5 WH, F Ankobra 2.8 WH, F Kpani-Nyila 3.0 WH, F Hwin 2.0 WH, F Pra 16.0 WH, F Ahwin 2.3 WH, F, SP Eture 3.7 WH, F, SP Amisa 6.3 WH, F Nakwa 3.6 WH, F Volta Delta wetlands 702.0 WH, F, SP

4.2.8 Depression wetlands The depression wetlands are those not linked to any significant watercourse. They are rather small in size and confined mostly to the western part of the country. Rainfall is high throughout the year and sustains such wetland despite the absence of any drainage e.g. Belibangara Lagoon. Table 4.6 lists some of the coastal wetlands, their sizes and uses or benefits.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 34

Table 4.6. List of selected Depression wetlands, approximate sizes and uses/benefits WH = wildlife habitat; SP = salt production; F = Fishing (Source: Armah, 1993b).

Name Size (km2) Uses Benefits Belibangara 0.5 WH, F Ndumakaka 0.2 WH Efasu 0.3 WH Ehuli 1.4 WH, F

4.3 Birds Ghana’s coastal wetlands form an ecologically important unit, providing feed- ing, roosting and nesting sites for thousands of migratory and resident birds. Eight of the coastal wetlands: Keta Lagoon, Songor Lagoon, Sakumo Lagoon, Korle Lagoon, Densu Delta, Muni Lagoon, Elmina Salt Pans and Esiama Beach, qualify as internationally important wetlands under the Ramsar criteria of supporting 20,000 waterfowls or 1% of the population of a waterfowl spe- cies.

Keta and Songor each hold over 100,000 seashore birds and supports interna- tionally important numbers of seven species of waders. Sakumo, Densu flood- plain, Korle and Muni each holds 23,000 – 35,000 birds and supports interna- tionally important populations of up to 6 wader species. Table 4.7 shows the wetlands utilized by the birds.

Figure 4.7 Ringed plover is a common migrating species wintering in lagoons in Ghana.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 35

Table 4.7. Important seashore bird sites in Ghana (Source: EPC, 1990)

Site Maximum Status of Sites Number of Birds Re- corded Esiama Beach 10,000 Important Elmina Salt Pan 5,000 Fairly important Muni Lagoon 12,000 Important Densu Delta and Panbros Salt Pans 30,000 Important Korle Lagoon 12,000 Important Sakumo Lagoon II 14,000 Very Important Laiwi Salt Pans 5,000 Fairly important Songor Lagoon Complex 55,000 Outstandingly important Atiteti (Volta Mouth) 9,000 Fairly Important Keta Lagoon Complex 55,000 Outstandingly important

4.3.1 Songor Lagoon The Songor wetland supports spectacular concentrations of seashore birds, comprising terns, waders, herons and ducks. The area serves as a stopover point and has a high rate of shorebird population turn over. The wetland supports in- ternationally important populations of seven species of waders: spotted red- shank, greenshank, ringed plover, curlew sandpiper, little stint, avocet and black-tailed godwit. The site has the highest tern count on the Ghanaian coast and supports nationally important populations (over 10% of the total coastal count) of at least 32 species of water birds. Table 4.8 presents the peak counts and national importance of the most abundant seashore bird species recorded at Songor.

Over 80% of the total number of species recorded in Songor is Palaearctic mi- grants. Migrant birds begin to arrive at the site in late August and their numbers peak in September-November. The birds start to leave the area at the onset of the dry season, when large sections of the lagoon dry up and by January, the bird population is less than 5% of the autumn peak.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 36

Table 4.8. Peak counts and national importance of the most abundant sea- shore birds recorded at Songor (as at 30th June 1991).

Species Max. count entire Peak % coast at Songor of entire coast SHOREBIRDS Black-winged stilt 12,460 4,390 35.2 Avocet 3,750 3,740 99.8 Pratincole 1,700 40 2.3 Ringed plover 6,160 3,010 48.9 White-fronted sand plover 110 70 63.6 Kittlitz’s sand plover 480 140 29.2 Grey plover 2,780 980 35.2 Knot 2,360 1,490 63.1 Sanderling 6,480 700 10.8 Little stint 12,350 2,530 20.5 Curlew sandpiper 27,980 6,920 24.7 Black-tailed godwit 1,590 200 12.6 Bar-tailed godwit 500 130 26.0 Whimbrel 460 30 6.5 Curlew 360 10 2.8 Spotted redshank 10,440 10,060 96.4 Redshank 450 50 11.1 Marsh sandpiper 290 160 55.2 Greenshank 8,350 5,070 60.7 Wood sandpiper 600 40 6.7 Common sandpiper 600 90 15.0 Turnstone 440 80 18.2 TERNS Caspian tern 440 110 25.0 Royal tern 7,550 2,570 34.0 Sandwich tern 6,080 5,120 84.2 Roseate tern 400 70 17.5 Common tern 12,660 11,900 94.0 Little tern 3,240 2,740 84.6 Black tern 20,680 18,060 87.3 OTHER WATERFOWL Long-tailed cormorant 790 110 13.9 Pink-backed pelican 900 410 45.5 Western reef pelican 1520 1,020 67.1 Western reef heron 6,400 4,460 69.7 Little egret 1,860 180 9.7 Grey heron 1,720 460 26.7 White-faced tree duck 7,060 410 2.4 Black headed gull 280 190 67.9 Lesser black-backed gull 760 540 71.1 Source - Ntiamoah- Baidu and Gordon, 1991

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 37

4.3.2 Muni Lagoon The Muni Lagoon supports an estimated population of 23,000 water birds, comprising 27 species of waders, 8 species of terns and 7 species of her- ons/egrets. The site is particularly important for terns: supporting 17-65 % of the total coastal count of terns. It also supports internationally significant num- bers of black-winged stilt (Table 4.9). Seashore bird populations are highest at Muni during August to April, when palaearctic migrants are present on the Ghanaian coast. Black-winged stilts nest on the site during May-July.

Table 4.9. Peak counts and national importance of the most abundant sea- shore bird species recorded at Muni (as at 30th June 1991).

Species Max. count Peak % entire coast at Muni of entire coast SHOREBIRDS Black-winged stilt 12460 150 1.2 Avocet 3750 50 1.3 Pratincole 1700 40 2.4 Ringed plover 6160 320 5.2 White fronted sand plover 110 25 22.7 Grey plover 2780 130 4.7 Knot 2360 30 1.3 Sanderling 6480 150 2.3 Little stint 12350 160 1.3 Curlew sandpiper 27980 840 3.0 Black-tailed godwit 1590 50 3.1 Bar-tailed godwit 500 30 6.0 Whimbrel 460 30 6.5 Marsh sandpiper 290 40 13.8 Greenshank 8350 320 3.8 TERNS Royal tern 7550 3200 42.4 Sandwich tern 6080 2100 34.5 Roseate tern 400 80 20.0 Common tern 12660 8210 64.8 Little tern 3,240 210 6.5 Black tern 20,680 3520 17.0 HERONS Western reef heron 1520 80 5.3 Little egret 6400 270 4.2 Great white egret 1860 20 1.1 Source: Ntiamoah-Baidu and Gordon, 1991

4.3.3 Sakumo Lagoon The recorded total of 66 species and the estimated population of 32,500 make the site the third most important seashore bird site on the Ghana coast. The site supports internationally important populations of six wader species: spotted redshank, greenshank, curlew sandpiper, little stint, black-tailed godwit and black winged-stilt (Table 4.10); and nationally important populations (> 10% of total coastal record) of at least 30 species of waterfowl. At certain times of the

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 38

year, Sakumo supports 90-100% of the total population of black heron, teal, black-tailed godwit and ruff recorded on the Ghana coast.

Over 80 % of the seashore bird species recorded at Sakumo is accounted for by palaearctic migrants. Migrant birds are most abundant on the site during Sep- tember to March/April. Resident birds recorded breeding on the site include Kittlitz’s sand plover, pratincole, little tern, pied kingfisher, yellow throated longclaw, plain-backed pipit, fantail warbler and red bishop.

Table 4.10. Peak counts and national importance of the most abundant sea- shore birds recorded at Sakumo (as at 30th June 1991).

Species Max. count Peak % entire coast at Sakumo of entire coast SHOREBIRDS Black-winged stilt 12,460 900 7.2 Avocet 3,750 450 12.0 Pratincole 1,700 1420 83.5 Ringed plover 6160 1040 16.9 White-fronted sand plover 110 20 18.2 Kittlitz’s sand plover 480 100 20.8 Grey plover 2780 300 10.8 Knot 2360 210 8.9 Sanderling 6480 180 2.8 Little stint 12350 2570 20.8 Curlew sandpiper 27,980 3270 11.7 Ruff 300 300 100 Black-tailed godwit 1,590 1460 91.8 Bar-tailed godwit 500 200 40.0 Whimbrel 460 40 8.7 Curlew 360 10 2.8 Spotted redshank 10,440 3280 31.4 Redshank 450 30 6.7 Marsh sandpiper 290 110 37.9 Greenshank 88350 1180 14.1 Wood sandpiper 600 190 31.7 Common sandpiper 600 150 25.0 Turnstone 440 140 31.8 Jacana 400 170 38.6 TERNS Royal tern 7550 340 4.5 Sandwich tern 6080 610 10.0 Roseate tern 400 40 10.0 Common tern 12660 2150 16.9 Little tern 3240 200 6.2 Black tern 20680 2630 12.7 OTHER WATERFOWLS Long-tailed cormorant 790 60 7.6 Squacco heron 600 110 18.3 Black heron 140 130 92.8 Western reef heron 1520 1020 67.1

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 39

Little egret 6400 1360 21.2 Great white egret 1860 380 20.4 Grey heron 1720 740 43.0 Glossy ibis 120 10 8.3 White-faced tree duck 17,060 640 3.7 Garganey 7450 830 11.3 Teal 140 140 100 Black-headed gull 280 30 10.7 Lesser black-backed gull 760 10 1.3 Source: Ntiamoah-Baidu and Gordon, 1991

4.3.4 Densu Flood Plain The Densu Flood Plain has a record of 57 species of seashore birds with an es- timated population of 35,000. The site is particularly important for terns, being the second most important tern site (after Songor) on the coast of Ghana. The importance of the Densu Flood-plain site is further enhanced by its population of roseate terns, a threatened species. The peak count of 200 roseate terns at this site accounts for approximately 20% of the European breeding population of this rare species. Other water birds, which occur in significant numbers on the site, include waders and herons.

The site supports internationally important populations of four species of wad- ers: curlew sandpiper, little stint, spotted redshank and black-winged stilt. Fif- teen other species of water birds occur in nationally important numbers (> 10% of peak counts for the entire coast, Table 4.11). Seashore birds are most abun- dant on the site from August to March. At least 70 species have been recorded on the site.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 40

Table 4.11. Peak counts and national importance of the most abundant sea- shore birds recorded at Densu Flood-plain (as at 30th June 1991).

Species Max. count Peak at % entire Entire coast Densu Delta coast SHOREBIRDS Black-winged stilt 12460 310 2.5 Avocet 3750 100 2.7 Pratincole 1700 330 19.4 Ringed plover 6160 1560 25.3 White-fronted sand plover 110 10 9.1 Kittlitz’s sand plover 480 30 6.2 Grey plover 2780 340 12.2 Knot 2360 30 1.3 Sanderling 6480 230 3.5 Little stint 12350 2610 21.1 Curlew sandpiper 27980 4730 16.9 Ruff 300 20 6.7 Bar-tailed godwit 500 10 2.0 Whimbrel 460 30 6.5 Curlew 360 5 1.4 Spotted redshank 10440 550 5.3 Marsh sandpiper 290 30 10.3 Greenshank 8350 390 4.7 Wood sandpiper 600 50 8.3 Common sandpiper 600 50 8.3 Turnstone 440 50 11.4 TERNS Royal tern 7550 2590 34.3 Sandwich tern 6080 1970 32.4 Roseate ternn 400 200 50.0 Common tern 12660 3130 24.7 Little tern 3240 930 28.7 Whiskered tern 100 30 30.0 Black tern 20680 2250 10.9 OTHER WATERFOWL Long-tailed cormorant 790 130 14.4 Squacco heron 600 20 3.3 Black heron 140 2 1.4 Western reef heron 1520 310 20.4 Little egret 6400 1630 25.5 Great white egret 1860 290 15.6 Black headed gull 280 60 21.4 Lesser black-backed gull 760 30 3.9

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 41

Table 4.12. Species of birds recorded breeding at the Densu Flood plain site.

Species Comments Black-winged stilt Nests, eggs, nestlings Pratincole Nests, eggs, fledglings Kittlitz’s sand plover Newly hatched young, fully fledged young follwing parent

Little tern Nests, eggs, fledglings Little bittern Nest parent nest visiting Pied kingfisher Nest holes in banks of salt pan Purple gallinule Nest and eggs Yellow crowned bishop Several nests, containing eggs, singing and displaying males

Red bishop Several nests, containing eggs, singing and displaying males

Yellow-throated long claw Singing birds African pied wagtail Singing and displaying birds Copper sunbird Singing bird Brown sunbird Singing bird Pin-tailedwhyday Displaying birds

4.3.5 Anlo-Keta Wetland The Keta wetland is the most important seashore bird site along the coast of Ghana. The site has all the 72 seashore bird species recorded for the Ghana coast. Current estimated seashore bird population is around 110.000, but the true population is believed to be several times higher than this estimate. The bird population includes several thousands of waders, terns, herons and ducks. At times, Keta alone holds 60% of the total population of waders on the Ghana coast (Ntiamoah-Baidu and Hepburn, 1988). The site supports internationally important populations of eight species of waders: spotted redshank, greenshank, ringed plover, curlew sandpiper, little stint, black-tailed godwit, avocet and black-winged stilt (Table 4.13).

The site is important for one species of tern, caspian tern; the entire coastal population of caspian tern is often found on the Keta Lagoon. The site contrib- utes 90-100 % of the recorded total count for ten species: black-winged stilt, knot, curlew, wood sandpiper, caspian tern, western reef heron, squacco heron, purple heron, white-faced tree duck and garganey. Eighteen other species occur in numbers, which account for over 50 % of the recorded coastal total popula- tion for the species.

The site is most productive during September to April. Presently the most im- portant areas for birds in the Keta wetland are the shallow waters and mud banks around Anloga, between Woe and Fiahor, around Adina and Afiadeny- igba. The Adina section alone often holds 10,000-15,000 curlew sandpipers, equivalent to 2-3 % of the estimated East Atlantic Flyway population of the species.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 42

Table 4.13. Peak counts and national importance of the most abundant sea- shore birds recorded at the Keta (as at 30th June 1991).

Species Max. count Peak % entire coast at Keta entire coast SHOREBIRDS Black-winged stilt 12,460 12,080 96.9 Avocet 3,750 1,560 41.7 Pratincole 1,700 1,010 59.4 Ringed plover 6,160 2,860 46.4 White-fronted sand plover 110 50 45.5 Kittlitz’s sand plover 480 390 81.3 Grey plover 2,780 1,390 50.0 Knot 2,360 2,340 99.1 Sanderling 6,480 580 8.9 Little stint 12,350 5,790 46.9 Curlew sandpiper 27,980 14,810 52.9 Ruff 300 140 46.7 Black-tailed godwit 1,590 1,270 79.9 Bar-tailed godwit 500 230 46.0 Whimbrel 460 60 13.0 Curlew 360 330 91.7 Spotted redshank 10,440 8,330 79.8 Redshank 450 170 37.8 Marsh sandpiper 290 260 89.6 Greenshank 8,350 6,910 82.7 Wood sandpiper 600 540 90.0 Common sandpiper 600 280 46.7 Turnstone 440 110 25.0 Jacana 400 280 70.0

TERNS Caspian tern 440 440 100 Royal tern 7,550 290 3.8 Sandwich tern 6,080 520 8.5 Roseate tern 400 10 2.5 Common tern 12,660 2,770 21.9 Little tern 3,240 810 25.0 Whiskered tern 130 130 100 Black tern 20,680 1,870 9.0

OTHER WATERFOWL Long-tailed cormorant 790 650 82.3 Pinked-backed pelican 900 690 76.7 Squacco heron 600 570 95.0 Black heron 140 40 28.6 Western reef heron 1,520 1,420 93.4 Little egret 6,400 3,980 62.2 Great white egret 1,860 1,650 88.7 Purple heron 100 100 100 Grey heron 1,720 1,170 68.0

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 43

Glossy ibis 120 80 66.7 White-faced tree duck 17,060 17,040 99.9 Garganey 7,450 6,910 92.7 Teal 140 110 78.6 Black-headed gull 280 100 35.7 Lesser black-backed gull 760 500 65.8 Little gull 225 130 59.1

Source: Ntiamoah-Baidu & Gordon, 1991

4.4 Endangered Species

4.4.1 Marine turtles Marine turtles found Marine turtles are listed as endangered and are among the marine animals under in Ghana protection by law in Ghana (L.I 685). Five species of marine turtles are found in the coastal waters of Ghana:

• The Hawksbill (Erectmochelys imbricate),

• The Leatherback (Dermochelys coriacea)

• The Loggerhead (Caretta caretta)

• The Green turtle (Chelonia mydas)

• The Olive Ridley turtle (Lepidochelys olivacea).

The Olive Ridley turtle is the most abundant species in Ghana (Carr and Camp- bell, 1995). Minor nesting of the leatherback has also been recorded (Márquez, 1990).

The marine turtles spend most of their life at sea, but during the breeding sea- son they go ashore and lay their eggs on sandy beaches.

Marine turtles breed- The sandy beaches of Ghana support the breeding of the Green turtle, the ing in Ghana Leatherback and the Olive Ridly turtle. They have been found to nest on the flat and sandy beaches of Old Ningo, Labadi, Chorkor, Elmina, Bortianor, Keta and Fete. The shoreline from Prampram to the Volta (a distance of 65 km) serves as the main turtle sites (Carr and Campbell, 1995). Minor number of turtles are nesting in the western part near Amansuri Wetland and Atuabo

Breeding The turtles come ashore to nest between August and March. Female turtles return to the beach on which they were hatched to lay their eggs. They visit the beach three to seven times during a nesting period. Each turtle lays about 350 to 500 eggs within a breeding season. The eggs are laid in holes in the sand, which the females dig with their flippers. The nests are normally located above high- tide level. After laying, the eggs are covered with sand. The female turtle then returns to sea, leaving the future hatchlings to fend for themselves. Incubation of the eggs takes about 2-3 months. After hatching the hatchlings fight their

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 44

way across the beach to the sea, often attacked by gulls and other predators. Marine turtles may nest every 1-4 years after reaching maturity, which is esti- mated to take 23 years (Eckert, 1993)

4.4.2 Manatees The Manatees are large aquatic mammals. Very little is known about the West African manatee (Trichechus senegalensis). They are considered rare and elu- sive. They are found in coastal marine and estuarine habitats as well as fresh- water along the West coast of Africa from the Senegal River south to the Kwanza River in Angola. Studies conducted by the Institute of Aquatic Biology of the CSIR and the Wildlife Department in Ghana indicate that the manatee could be found in the Abby Lagoon and the Volta estuary. There is apparently a comparatively high abundance of the species in Volta Lake compared to other sites in West Africa.

Figure4.8. Rare manatee from the Volta estuary. Photo credit: P. K. Ofori- Danson

4.5 Protected Areas There are five protected wetlands along the coast of Ghana. These are

• The Muni Pomadze Lagoon

• The Densu Delta

• Sakumo Lagoon

• Songor Lagoon

• Anlo-Keta Lagoon complex

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 45

These sites are of international importance as feeding grounds for large concen- trations of more than 70 species of migratory and resident water birds as well as breeding sites for 3 species of marine turtles (cf. Section 4.3 and 4.4). They were all designated Wetlands of International Importance according to the Ramsar convention on 14 August 1992. The characteristics of the Ramsar sites are presented in Tables 4.14 - 4.18 below.

Table 4.14 Characteristics of the Muni - Pomadze Lagoon Ramsar site. (Lin- coln, Fishpool and Evans, 2001).

Location West of Winneba approximately 55 km west of Accra, International Ramsar site no. 563. Designation National Two Forest Reserves (Yenku and Winneba Fuelwood) in the northern Designations part of the area. Area 8,670 ha Importance This coastal wetland serves as feeding, breeding and roosting grounds for waterbirds such as terns, waders, and herons. It also has a high di- versity of mammals and there are turtle nesting sites on the beaches. Principal The site features are coastal saline semi-closed lagoon surrounded by Features sand dunes, areas of marshland and degraded forest and scrubland. Two seasonal rivers, the Aboaku and Pratu feed the lagoon with freshwater and the lagoon opens into the sea during the rainy season. The lagoon has a surface area of 4,500 ha, an average depth of 0.6 m, a o maximum depth of 1m and an average salinity of 39.3 /oo. Flora The eastern fringes of the lagoon are marginally covered with Avicennia africana mangroves. The drier areas are predominantly grassland, the main species being Imperata sp., Cyperus sp and Panicum sp. The vegetation in the seasonally flooded areas consists mainly of Sesuvium portulacastrum and Paspalum vaginatum. The degraded forests and semi-natural scrubland are dominated by a mixture of coarse grasses and sedges (Vetiveria spp, Brachiaria spp), herbs (Cassia sp. and Azadirachta indica) as well as shrubs (Bonnetia sp., and Abutilon sp.). The adjacent forest reserve is dominated by Cassia sp., Eucalyptus sp., and mahogany. The vegetation on the narrow strip of sand dune, which separates the lagoon from the sea, is mainly Sporobolus sp. and fringed by coconut palms (Cocos nucifera). Fauna The site supports an estimated population of 23,000 waterbirds com- prising 27 species of waders, 8 species of terns and 7 species of her- ons/egrets. The site is particularly important for terns. Water bird popu- lation is highest during August to April. There are 114 species of terres- trial birds and the area has several species of mammals. Three species of marine turtles are reported to nest on the beaches (Lepidochelys olivacea, Chelonia mydas and Dermochelys coriacea) Human Fishing is one of the main activities in the lagoon area, as well as col- Activity lection of fuel wood and hunting. The area is known as one of the most important sources of bush-meat in the country. Part of the grassland is used for cattle and sheep grazing. Farming and stone mining are also taking place in the surrounding lands.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 46

Table 4.15. Characteristics of the Densu Flood-plain Ramsar site. (Lincoln, Fishpool and Evans, 2001).

Location Ca 11 km west of Accra International Ramsar site no. 564. Designation National None. Designations Area 4,620 ha Importance This site is a good representative example of a coastal wetland on the south coast of West Africa. The site serves as feeding, breeding and roosting grounds for waterbirds, including the globally threatened Ro- seate tern. In addition there are turtle nesting sites on the beaches. Principal The site is a flood-plain containing, open lagoon, sand dunes, scattered Features mangrove stands, saltpans, marsh and scrub. There is no direct outlet channel to the sea, but the lagoon often overflows into the sea after heavy rains. Seasonally inundated grasslands extend 27.5 km upstream from the sea. Tidal influences extend upstream for some 10 km. Flora Sesuvium portulacastrum, Paspalum vaginatum, Sporobolus virginicus, Cyperus articulatus and Imperata cylindrica form the main vegetation of the floodplains. Scattered stands of mangrove Avicennia africana are found. Fauna The Densu Flood Plain has a record of 57 species of seashore birds with an estimated population of 35,000. The site is particularly important for terns. Its population of the globally threatened Roseate tern further en- hances the importance of the Densu Flood Plain site. A total of 15 fin fishes belonging to 14 genera and 9 families occur. Sarotherodon melanotheron and Tilapia zillii are the dominant species. Three species of marine turtles are reported to nest on the beaches (Lepidochelys olivacea, Chelonia mydas and Dermochelys coriacea) Human The main activities within the wetland are the large scale commercial Activity salt operations and lagoon fisheries mainly for Tilapia and lagoon crab. Local people gather fuel wood in the area and the site is used for farm- ing.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 47

Table 4.16. Characteristics of the Sakumo Lagoon Ramsar site. (Lincoln, Fishpool and Evans, 2001).

Location Ca 3 km West of Tema International Ramsar site no. 565. Designation National None Designations Area 1,340 ha Importance The site is a good representative example of a wetland on the south coast of West Africa. It is an important wetland for many species of waterbirds. In addition there are turtle nesting sites on the beaches. Principal The site includes a brackish-saline lagoon whose main habitats are open Features lagoon, surrounding flood-plains, freshwater marsh, and coastal savan- nah grassland. The lagoon is separated from the Sea by a narrow sand dune, on which the Accra-Tema road is built. It is connected to the sea by a narrow non-functional (permanently open) sluice. Flora Avicennia africana forms the main element of the mangrove commu- nity, Paspalum vaginatum, Sesuvium portulacastrum, and Philoxerus vermicularis are the main elements of the saltmarsh, while Typha aus- tralis is mainly associated with the estuarine brackish water/freshwater marsh. Fauna Seventy species of waterbird have been recorded at the site with esti- mated maximum numbers of some 30,000 birds. Thirteen fish species belonging to thirteen genera and eight families occur along with Sarotherodon melanotheron, which constitutes about 97 % of the fish population. Three species of marine turtles are reported to nest on the beaches (Lepidochelys olivacea, Chelonia mydas and Dermochelys co- riacea). Human Fishing is the main livelihood of the communities around the lagoon. Activity Farming and some industrial activities also occur near the site.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 48

Table 4.17. Characteristics of the Songor Lagoon Ramsar site. (Lincoln, Fishpool and Evans, 2001).

Location About 100 km east northeast of the city of Accra, on the southeast coast, in Dangme East district, Greater Accra region International Ramsar site no. 566. Designations National None Designations Area 28,740 ha Importance The site is a good representative example of a wetland on the south coast of West Africa. It is an important wetland for many species of waterbirds. In addition there are turtle nesting sites on the beaches Principal The site is a closed lagoon with inundated mudflats that form the main Features habitat within the site. The lagoon is separated from the sea by a narrow sand-dune on which small villages are situated. The lagoon is 16 km long and 7 km wide at its widest point, with an average depth of 1.75 m and a maximum of 4 m, within the floodplain of the River Volta. Flora The vegetation of the site is composed of Paspalum vaginatum, Cype- rus articulatus, Sesuvium portulacastrum and Eleocharis mutata that dominate the floodplains. Andropogon guyanus, Heteropogon contortus and Azadirachta indica dominate the catchment areas. Degraded man- groves with Rhizophora racemosa and Avicennia africana are found along the creeks. Fauna The Songor wetland is the second most important site, after Keta for waterbirds on the Ghanaian coast supporting an estimated number of over 100,000 birds Three species of marine turtles are reported to nest on the beaches (Lepidochelys olivacea, Chelonia mydas and Dermoche- lys coriacea). Human Local communities depend on the site for fish resources, farming and Activity salt production.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 49

Table 4.18. Characteristics of the Anlo- Keta Lagoon complex Ramsar site (Lincoln, Fishpool and Evans, 2001).

Location About 140 km east-northeast of Accra, on the south coast of the region of Volta, southeast Ghana. International Ramsar site no. 567. Designations National None Designations Area 127,780 ha; Importance Most important seashore bird site along the Ghana coast. The site is a good representative example of a wetland on the south coast of West Africa. Principal Part of the Volta estuary comprising a complex of lagoons with varying Features salinity (including Avu, Keta, Nogui, Logui and Angaw lagoons) and several small islands. The surrounding flood-plain consists of marsh, scrub mangrove and farmland. Flora There are substantial mangrove stands and stands of Ruppia grasses in the Lagoon. The site falls within the coastal savannah region of Ghana. Grasses dominate the vegetation, with patches of trees and shrubs. An- dropogon gayanus, and Heteropogon contortus dominate the catchment and the floodplain areas. Fauna The area is abundant with birds and has all the 72 seashore bird species recorded for the Ghana coast. Current estimated seashore bird popula- tion is around 110,000. Fish and butterfly species abundant. The endan- gered waterbuck is also found in the area. Human The site is used for its rich fish resources, salt production, charcoal pro- Activity duction, and hunting.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 50

5 Socio-economic Conditions The coast and the sea are very important for the people of Ghana and for the economy of the country. The main economical activities in the coastal zone are fishing, farming, manufacturing industry, salt production, oil and gas extraction and tourism.

5.1 Population and Settlements In Ghana, the coastal zone represents only approximately 6.5 % of the total area of the country but around 25 % of the population. High population densities (>500 inhab./km2) are present at the Accra – Tema area, Cape Coast and Se- kondi-Takoradi area.

A large number of minor towns and settlements are scattered along the coast and the majority are hosting fishing communities. Approximately 185 villages and towns are registered as having fishing activities (Bannerman et al. 2001)

Administratively, the coast is divided into 4 regions and 21 districts of which 17 districts are bordering the seashore while 4 districts are further inland but still considered to be part of the coastal zone (WB and EPA, 1996). The admin- istrative features are summarised into Table 5.1.

The population along the coastline represents 7 distinct ethnic groups with the Nzema dominating the coastal stretch from the border with Cote d’Ivoire to Axim (~105 km coastline), the Ahanta living from Dixcove to Sekondi (~80 km), the Fante living from Shama to Mankoadze (~ 150 km), the Efutu – Awutu living from Winneba to Nyanyano (~25 km), the Ga living from Kokro- bite to Kpone (~45 km), the Dangbe living from Prampram to Ada (~70 km) and the Ewe living from Ada to Aflao (~75 km).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 51

Table 5.1 – Regions and districts in the coastal region and population, area and length of shoreline. (Data from 2000 Census – Ghana Statistical Service, 2002; WB and EPA, 1996)

Region District Population Area Coastline (Code no) (2000) (sq km) (km) Western Jomoro (D101) 111,348 1350 55 Nzema East (D102) 142,871 2088 51 Ahanta West (D103) 95,140 568 57 Shama/Ahanta East (D104) 369,166 417 32 Central Komenda/Edena/Eguafo/Abrem(D201) 112,437 401 29 Cape Coast (D202) 118,106 125 12 Abura Asebu Kwamankese (D203) 90,093 401 4 Mfantseman (D204) 152,855 522 46 Gomoa (D205) 194,792 842 19 Ajumako Enyan Esiam (D209) 91,965 458 0 Awatu Efutu Senya (D206) 169,972 713 39 Greater Ga (D302) 550,568 562 0 Accra Accra (D301) 1,658,937 345 34 Tema (D303) 506,400 476 24 Dangme West (D305) 96,809 962 30 Dangme East (D304) 93,112 772 38 Volta Tongo North (D405) 130,388 1836 0 Tongo South (D401) 64,811 503 0 Akatsi (D404) 93,477 900 0 Anlo Keta (D402) 133,661 728 55 Ketu Denu Dzodze (D403) 237,261 632 24 Total 5,212,175 15601 549

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 52

Fig 5.1 – Administrative boundaries in Ghana. (Data source: web informa- tion and CIESIN).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 53

Fig 5.2–Population densities in Ghana (Data source: web information and CIESIN).

5.2 Fishery

5.2.1 Introduction Fishery is very important in Ghana. The fishing industry is one of the most promising in West Africa, in terms of resources and experience of the people engaged in the industry. Structurally, the industry is categorized into artisanal, inshore, industrial and tuna fishing.

Artisanal fishery dominates the industry, providing about 70 % of the total ma- rine production in the country. This fishery is usually year-round but shows

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 54

definite peaks and lows in the course of the year. Throughout the coastal areas of Ghana, the artisanal fisheries rely on fish from both the inshore and offshore marine environment.

Coastal lagoons and estuaries are also very important sources of fish and shell- fish. Although fish landings from any one lagoon or estuary may be compara- tively small, these water bodies do provide significant quantities of fish prod- ucts for subsistence purposes.

Fish is the single most important low cost animal protein source in the country and accounts for about 60-70 % of the total animal protein intake by the aver- age Ghanaian. A substantial part of this fish intake is derived from the coun- try’s marine capture fishery, whilst aquaculture contributes only a small per- centage (Fig. 5.3).

100

80

60 % 40

20

0 1997 1999 2001

Marine catch Inland catch Aquaculture

Figure 5.3 Fishery and aquaculture in Ghana. Distribution of total catch on marine catch, inland catch and aquaculture. Percentage of total catch

5.2.2 Marine fisheries The marine fishery is the largest fishing industry in Ghana, accounting for the largest percentage of the labour force involved in the fishing industry. It is made up of men, carrying out fishing and women, who are mainly involved in processing and marketing. The marine fishery resources may be broadly placed in four categories based on the bathymetric distribution as follows:

• Small pelagic species: these are exploited by both artisanal and indus- trial fishers using small purse seines, beach seines and various types of nets. Species caught are the round sardine (Sardinella aurita), flat sar- dine (Sardinella maderensis), anchovy (Engraulis encrasicolus) and the chub mackerel (Scomber japonicus).

• Large pelagic species: these include the Yellowfin tuna (Thunnus al- bacares), skipjack (Katsuwonus pelamis), bigeye (Thunnus obesus),

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 55

black skipjack (Euthynnus alleterratus) and frigate tuna (Auxis sp.). These are exploited using baitboat/pole and line vessels.

• Coastal demersal species: these species include red Pandora (Pagellus bellotti), red snapper (Lutjanus fulgens), burrito (Brachydeuterus auri- tus), Congo dentex (Dentex congensis), surgeon fish (Acanthurus mon- roviae), barracuda (Sphyraena sphyraena), cassava fish (Pseudotolithus senegalensis), tongue sole (Cynoglossus senegalensis), crevalle jack (Caranx hippos), blue-spotted sea bream (Sparus caeruleostictus), and triggerfish (Balistes capriscus). A variety of nets are deployed for the capture of these fishes.

• Deep water demersal species: these are in waters of depth between 200 and 300 m. They include the blackmouth croaker (Penteroscion mbizi), silver rag driftfish (Paracubiceps ledanoisi), deep-sea red crab (Geryon maritae), spinous spider crab (Maja squinado) and deep-water rose shrimp (Parapenaeus longirostris).

Marine fishing is carried out along the whole coast of Ghana, but it is most in- tensive east of Cape Three Points, where the industry is in the hand of Fante, Gã and Ewe fishermen.

Fishing fleet and fishing methods The marine fishing fleet can be classified into 4 main groups; canoes, inshore vessels, deep-sea vessels (industrial trawlers and shrimpers) and tuna vessels.

Canoes The canoe fishery dominates the number of vessels, employment and fish landings. The number of canoes has fluctuated but currently stands at about 10,0000, out of which 52.6 % are motorized. The canoes operate from about 185 fishing villages, utilizing 304 landing sites (Table 5.1).

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 56

Figure 5.4. Canoe landing site near Dwomba

The canoes use a wide variety of gears, including purse seines (Watsa and Poli), beach seines, drift gill nets (including Ali nets and nifa nifa), set gill-nets and hook and lines (Doyi, 1984).

Purse seines are surrounding nets, which are used to surround schools of fish. A purse seine is basically a long net wall that is set around a school of fish from the canoe. The nets are provided with a so-called purse line at the bottom of the net, which enables it to be closed like a purse and thus retain most of the fish surrounded. The most common purse nets used in Ghana are the Watsi and Poli purse seines.

Beach seines are operated from the beach or on the banks of the lagoons. The beach seines consist of a net bag and two net wings to each of which are at- tached a long drag rope. The seine is set from the beach using a canoe and dragged to land by two groups of men and women pulling in each of the two drag ropes.

Drift gill nets are long net walls allowed to drift freely along with the currents often with the craft to which they are attached. Fish that swim into the nets are caught by gilling, entangling or enmeshing them in the netting. Drifting nets include among others so-called Ali nets and nifa-nifa nets.

Set gill nets are basically net walls, which are fixed to the seabed or at a certain distance above by means of anchors or weights. Fish that swim into the nets are caught by gilling, entangling or enmeshing them in the netting.

Hook and line are used with bait placed on hooks, which are attached to a line. The bait attracts the fish.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 57

Table 5.1. Number of landing sites, canoes and fishermen in all 17 coastal Administrative Districts (Source: Bannerman et al., 2001).

District Landing Number Number of fishermen sites of canoes Ketu District- Volta Region 8 195 5457 Keta District- Volta Region 34 323 6406 Sub Total 42 518 11863 Dangbe East – Gt. Accra 21 477 12041 Dangbe West – Gt. Accra 16 836 11744 Tema District – Gt. Accra 7 563 5195 AMA District- Gt. Accra 18 852 10263 Ga District – Gt. Accra 5 229 1783 Sub Total 67 2957 41026 Efutu-Ewutu Senya District Central Region 7 442 9427 Gomoa District – Central Region 19 729 5238 Mfantseman District – Central Region 34 1128 1250 Cape Coast District – Central Region 14 198 2168 Abura-Asebu-Kwamankese Central Region 8 425 3396 Komenda-Edina-Eguafo-Abrew – Central Region 19 853 9430 Sub Total 101 3775 45909 Shama-Ahanta East District Western Region 15 1086 10392 Ahanta West District Western Region 21 824 4629 Nzema East District Western Region 31 622 5766 Jomoro District Western Region 27 199 3571 Sub Total 94 2731 24358 Grand Total 304 9981 123156

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 58

Figure 5.5. Beach seining (Volta Region near Adafoah)

Inshore vessels Inshore vessels are inboard-engine vessels of up to 30.5 m overall length. Most of these vessels are equipped for purse-seining and trawling. There are harbours for these vessels at Tema, Apam, Elmina, Aboadi, Takoradi and Axim

Deep sea vessels The deep-sea vessels are also trawlers but equipped with freezers. They are more than 30.5 m in length. They are based in the harbour at Tema.

Tuna vessels The locally registered tuna vessels are pole and line vessels. There are 26 baitboat/pole and line vessels with a carrying capacity between 200 and 400 Mt of frozen tuna, which undertake trips of nearly one month at sea.

Fishing season The fishing season is closely influenced by the upwelling phenomenon, which is from January to April (minor upwelling) and July to September (major up- welling). Trawling takes place all year round. Catches from trawls appears to be less abundant in the hot season. Canoe fisheries for demersals are seasonal and alternate with the fishery for small pelagics when they are available.

Fish landings Fish productivity is propelled by the two seasonal local upwellings. Peak catches of both pelagic and demersal fishes are taken during the major upwell- ing.

The annual fish production ranges from 290,000 to 472,000 metric tonnes for a 5-year period 1998-2002 constituting about 5 % of the agricultural GDP. About 80 % of the annual landings come from marine sources, 19 % from inland fish- eries, principally, the Volta Lake and 1 % from freshwater fish culture. The an- nual fish requirement is estimated to be about 700,000 metric tonnes.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 59

Table 5.2. Fisheries data for a 5-year period (1998-2002) in metric tonnes.

1998 1999 2000 2001 2002 Fish production 472,039 422,041 450,000 - 290,008 Fish requirement 736,000 754,000 772,000 792,000 720,000 Fish consumption 411,905 405,236 486,967 486,061 - Fish import 17,100 52,156 64,024 105,619 144,597 Fish export 57,855 68,962 44,350 73,299 3,827

Figure 5.6. Fish landing site, Elmina.

Fish processing and marketing The fisheries sub-sector provides employment for at least 500,000 fishers, processors, traders, mechanics and boat builders who together support twice as many dependants.

Nearly half of the artisanal fisheries labour force is women who are engaged in processing and selling of fish. They are responsible for the marketing of 60-90 % of the fish produced. The landed fish are bought by fishmongers who process them before selling. Some women only process and sell fish obtained from their husbands’ share of the catch to wholesalers or retailers. Others buy fish in addi- tion to their husbands’ share, usually from fishermen who are indebted to them. Furthermore, some of the women are employed as hired labour in fish process- ing, with the aim of earning enough money to start their own fish marketing ventures.

Smoking, sundrying, salting, fermenting and frying, are generally the methods involved in fish processing. These are then taken to the market centres for sale. Smoking is most widely practised, especially, smoked sardinella, and anchovy are highly appreciated.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 60

Fish is transported up country from fishing villages in trucks on an individual or shared basis to be marketed. The transactions and economics of fish market- ing depend highly on the seasonal and local fluctuations in catches.

Figure 5.6. Fish processing (from Dwomba)

5.2.3 Lagoon fisheries In Ghana, coastal lagoons support a thriving artisanal fishery of both subsis- tence and commercial importance. There are over 90 coastal lagoons along the entire coastline, which serve as nursery grounds for a variety of fish, which are vulnerable to the fishery throughout the year. Fishing in the lagoons may either be seasonal or all year round. In general, productivity in the lagoons peaks up during the wet season, from May to July and to a lesser extent from August to November following the two rainfall regimes experienced in southern Ghana.

Among the various fishing methods employed in the coastal lagoons are cast nets, set-nets, drag nets, gill nets, hook and line, bottle traps, crab traps, rope

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 61

fishing, acadja fishing and bamboo traps. These may be deployed from canoes or by wading through the water.

Fish populations of these lagoons are dominated by the cichlids; of which Sarotherodon melanotheron, Tilapia guineensis and Hemichromis fasciatus are the major species. Most of the lagoon fish are small (6-8 cm). Other fish spe- cies in the lagoons are Tilapia zillii, Oreochromis niloticus, H. bimaculatus, Ethmalosa fimbriata, Mugil spp. and the shellfishes, Anadara senilis and Tym- panotonus fuscatus. Two species of crustaceans are also fished in commercial quantities in lagoons that are occasionally open to the sea or receive over-wash from the sea at high tides. These are the blue-legged swimming crab (Callinec- tes amnicola) and to a lesser extent, the marine shrimp (Penaeus notialis).

5.2.4 Aquaculture Even though the potential for marine aquaculture exist in Ghana there are yet no commercial large-scale projects operating. A few small-scale aquaculture ponds are found in the coastal zone for instance at Tema. There is also an ex- perimental marine aquaculture facility at Ada.

5.3 Oil and Gas Extraction Over the years, more than 30 wells have been drilled. This has led to three im- portant discoveries; The Saltpond-, The North Tano- and the South Tano oil and gas fields.

The Saltpond Field initially had a production rate of 4000 barrels of oil/day in 1977 when it began. Output, however, dropped steadily and the field was closed down in 1986. Gas reserves of the Saltpond Field are estimated to be 30 billion cubic feet while crude oil deposits were less than 50 million barrels.

The North and South Tano Fields are situated about 18 and 35 km offshore in the south-west of Ghana, respectively. Explorations and appraisal have been carried out in these fields over the past 20 years. Philips Petroleum, the interna- tional company, which made the discoveries, estimated about 131 million bar- rels of oil in place in the South Tano Field with about 850 billion cubic feet of gas. The same company estimated a reserve of 135 million barrels of oil for the North Tano Field. Some appraisal wells were drilled by Petro-Canada Interna- tional Assistance Corporation in the South Tano Field in 1984. The offshore concession and exploration areas for Oil and Gas in Ghana is shown in Figure 5.4 below.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 62

Figure 5.7. Offshore concession and exploration areas for Oil and Gas in Ghana.

5.4 Salt Production Salt production takes place within or on the edges of coastal lagoons. Extensive production occurs at the Songor, Sakumo, Keta, Djange, Old Ningo, Prampram, Laloi, Nyanya, Nakwa, Apabaka, Iture, Brenu, Akyinmu, and Ahwin Lagoons.

Three different methods are applied for salt production in the coastal areas of Ghana:

• The traditional method where brackish water is allowed to evaporate within the lagoons during the dry season (September to March). This simple method is practised in the Keta, Songor, and Nyanya Lagoons.

• The second method of production entails the use of salt pans con- structed with lagoon mud. The pans are filled with water from the la- goon or tidal channels at high tide when more saline water is available. Sometimes such pans are made of more permanent material e.g., con- crete. Examples of this method can be found in the Nyanya and Keta Lagoon areas.

• The third method is relatively capital intensive and involves pumping of sea water using motorized pumps into large concrete concentration pans to evaporate. Used to be practised in areas like Iture and Djange.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 63

Figure. 5.8. Saltpans in Keta Lagoon using small dikes of mud

5.5 Industrial Development More than 60 % of the manufacturing industries in Ghana are situated in the larger towns along the coast. Most industries are encountered in the Accra- Tema area, followed by Takoradi and Cape Coast. The industries include a wide variety of food-processing-, metal production-, textile-, chemical-, and cement factories as well as oil refineries. A free port zone has just been estab- lished at Tema and it is expected to further enhance the industrial development. The Aboadze thermal plant near Takoradi is another recent large industrial es- tablishment in the coastal zone.

5.6 Farming in Coastal Areas There is a quite varied production of crops in the coastal zone of Ghana includ- ing root crops, grains and vegetables. Two important crops of the coastal zone of Ghana are coconuts and shallots.

Coconuts The main commercial coconut production areas are in the Central and Western Regions. It is estimated that 75 % of all coconut production comes from the Western Region and 17 % of the regions population being dependent on it as their principal source of income. Overfield et al. (1997) estimate that the indus- try is worth US$8.84 million.

Shallot Shallot farming is an important economic activity along the eastern coastal strip lying between the sea and Keta Lagoon. It constitutes a major source of income for many households. The shallots are grown either in monoculture or inter- cropped with other vegetables such as okra, pepper, tomato and cowpeas.

Cattle Semi-nomadic rearing of cattle is an important livestock activity in the coastal savannah stretching from Winneba in the Central region to the Volta Region.

5.7 Tourism Tourism has emerged in recent times as an important foreign exchange earner for Ghana. The coastal area of Ghana offers varied opportunities for tourism

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 64

and holds significant potentials. The major assets are the broad beaches and cliffs, the coastal lagoons and estuaries having a rich birdlife, historical monu- ments (forts, castles, light houses etc.) and cultural activities.

The assets thus attracts various types of tourists among others the important cultural and heritage tourism related to the history of slave trades and forts, eco-tourism and beach and water sport tourism all associated to the coastal zone.

The major costal tourism attraction sites are in Keta, Ada, Ningo, Prampram, Tema, Labadi, Accra, Winneba, Kromantse, Cape Coast, Elmina, Brenu- Akyinim, Komenda, Sekondi-Takoradi, Axim and Busua.

There are 28 waterfront hotels with approximately 1000 beds registered by the Tourist Board of Ghana. Furthermore, there are a similar number of minor re- sorts and campsites at waterfronts. Only the 28 officially registered hotels are depicted in the Atlas.

5.8 Historical Monuments A number of forts and castles are found along the coast of Ghana. Many are quite well preserved, others are mere ruins. They were built by Europeans, i.e. Portuguese, Dutch, French, Britons, Brandenburg-Prussians, Danes and Swedes during the period 1482 -1837. The forts and castles were in fact built as forti- fied trading stations for the trade with gold, ivory and, most important, slaves, which were destined for sale to the plantation owners in the New World. Rec- ognizing their unique place in an unfortunate chapter of the world history. UNESCO has designated Ghana’s castles and forts as World Heritage Monu- ments (Anquandah, 1999). Table 5.3 provides an overview of the existing cas- tles and forts (including ruins) of Ghana.

Table 5.3. Existing forts and castles (including ruins and remains) from West to East.

Location Name of fort History/remarks Beyin Fort Apollonia Built by Britain in 1770. It was the last fort built by the British on the Gold Coast. It was renovated in the Late 1950ies and con- verted to a resthouse in the 1970s. Axim Fort Sâo Antonio Built by the Portuguese around 1515. The fort was captured by (Fort St Anthony) the Dutch in 1642 and remained under Dutch control until it was handed to Britain in 1872 Princes Fort Gross Freder- Built by the Brandenburg-Prussians in 1683. In 1717-1724 held town icksburg by an Ahanta chief. Taken over by Netherland in 1725 and later by Britain in 1872 Akwidaa Fort Dorothea The fort is a ruin today (Fort Akodaa) Dixcove Fort Metal Cross Built by the British in the period 1692-1696. It was then called Dixcove Fort. The fort was captured by the Dutch in 1868 and renamed Fort Metalen Kruiz (Fort Metal Cross), only to be re- turned to Britain in 1872 Butre Fort Batenstein Constructed by the Dutch in 1656. Handed over to Britain in

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 65

1872. Today a substantial by somewhat overgrown ruin. Sekondi Fort Orange Built by the Dutch in 1690 and taken over by Britain in 1872. The fort is still in use as a lighthouse Komenda Fort Vreedeburg Built by the Dutch in 1682. Only a little ruins remains today Komenda Fort English Built by the British in 1687. Only a little ruins remains today Shama Fort St. Sebastian Built by the Portuguese in 1523. In 1638 captured by the Dutch. Taken over by the British in 1872. Elmina Fort St. Jago Built in 1665-1666 by the Dutch to protect St. Georges Castle Elmina St. Georges Castle Founded in 1482 by the Portuguese. It is the oldest extant colo- (Elmina Castle) nial building in sub-Saharan Africa. The Portuguese held the Castle for 150 years and in 1637 taken over by the Dutch. Was sold to Britain in 1872. Cape Cape Coast Castle The Portuguese built a trade lodge on the site in 1555. Then the Coast Swedes built a permanent fort (Carolusburg) in 1653. During the next 11 years, the Danes, the local Fetu chief and the Dutch each in turn captured and held Carolusburg for a time. Then in 1665 it was captured by the British. Served as a seat of the British gover- nor. Cape Forts Victoria and Small Outpost look - out forts for Cape Coast castle. Fort Victoria Coast William was constructed in 1837 and fort William in 1820. Fort William is now a lighthouse. Moree Fort Nassau Built by the Dutch in 1612. This was the first fort built by the Dutch on the Gold Coast. Now a substantial ruin Anomabu Fort Charles In 1630 the Dutch built a fort at Anomabu, only to abandon it in 1664 due to pressure from the British, who built Fort Charles on the site in 1674. Britain left the fort due to disagreements with the local traders and destroyed the fort so that it could not be cap- tured by a rival power. The British built a new fort Charles over the foundations of the old fort in 1756 Saltpond Fort Amsterdam Dates back to 1631 and was the first fort built by Britain on the Gold Coast. Destroyed in an attack by the people of Anoma in 1811. It was restored in 1951 Apam Fort Built by the Dutch in 1697, captured by the British in 1782, re- Leydsaamsheid turned to the Dutch in 1783 and finally handed over to Britain in (Fort Patience) 1868. It is now a resthouse. Winneba Winneba was the site of an important British fort from 1673 to 1812. Traces of the old fort can be seen in the Methodist Church built on the site in late 19th century Senya Fort Good Hope The Dutch built a small trading lodge in 1660 in Senya Beraku. Beraku The lodge was abandoned shortly afterwards, but in 1704 the Dutch returned and built Fort of Good Hope. The fort was handed over to Britain in 1868. In the 1980ies the fort was restored as a joint historical monument and resthouse Accra James Fort Built by the British in 1673 Accra Ussher Fort Built by the Dutch in 1652. Taken over by the British in 1782. Accra Christiansborg Built by the Danes in 1661. It was briefly occupied by the Portu- Castle (Osu Cas- guese in 1679, but returned to Denmark in 1693. After that the tle) castle remained the Danish headquarters for 150 years, before being sold to Britain with four other Danish forts in 1850. The castle has been seat of the Government from 1876 to the present day.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 66

Prampam Fort Vernon Built in 1742 by Britain. Only some traces of the fort remain in the wall of a guesthouse Old Ningo Fort Fredensborg Built by the Danes in 1735. Very little remains of the fort Keta Fort Prinsensteen Constructed by the Danes in 1784 and sold to Britain in 1850. Today it is essentially a ruin, a large part of the fort being de- stroyed by waves during a storm in 1980.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 67

6 Environmental Degradation

6.1 Pollution There are three major sources of pollution of the coastal area:

• Municipal waste

• Industrial waste

• Agriculture

Other types of pollution include tar-balls grounded on the beaches as a result of ballast water discharge from petroleum tankers, and dumping of disused vessels along the shore.

6.1.1 Municipal waste Municipal waste include sewage, faecal waste and garbage from households.

Municipal sewage Individual disposal of household sewage is widespread along the coast and only Tema has a fully centralized sewer system. However, the sewage is discharged into the sea untreated. In Accra, only a small section is connected to a central sewer system discharging the sewage untreated into the sea.

Recently, stabilization ponds have been installed for the new residential areas. The drainage systems for storm-water in the twin cities are similar with dis- charges into the Chemu and Korle Lagoons for Tema and Accra respectively. The Chemu lagoon has virtually disappeared while the Korle Lagoon, which was severely silted and colonized by Avicennia mangroves and other opportun- istic species capable of coping with the high organic content of the lagoon, is being dredged. The drainage systems of Accra and Tema are also used for the disposal of substances such as used engine oil from garages.

Faecal waste and The most depressing of the municipal sources of pollution is that of faecal garbage waste and garbage from the numerous settlements along the coast. If beach tourism is to grow, appropriate steps must be taken to provide sanitation facili- ties to handle this menace. It will also require a serious education effort on the part of the relevant authorities. The role of the district assemblies, local coun- cils and chief fishermen, in this regard, as instruments of change should be cru-

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 68

cial as this would involve a change in an attitude which unfortunately has a long tradition.

Despite the poor sanitation levels in most of the coastal towns, there has been only one study covering the entire coast on the status of bacterial pollution (Afoakwa et al., 1988). Ten sampling sites were selected based on the existing and proposed tourist resorts and recreational beaches. It was established that faecal pollution existed at all the points monitored. The total coliform counts ranged from 4 per 100 ml of sea water at Prampram Beach and Newtown (near the Côte d’Ivoire border) to 2,400 per 100 ml of sea water at Aflao, Bortianor Beach and Victoria Park (Cape Coast) and Saltpond. Faecal coliform counts ranged from 2 per 100 ml of sea water (at Prampram Beach) to 2,400 counts per 100 ml at Aflao, Bortianor Beach and Victoria Park. There is the need for regular bi-annual surveys of the coastal waters, especially amenity beaches for faecal coliform to determine their health status.

6.1.2 Industrial waste The main producers of industrial wastes are the textile, food, petroleum refiner- ies and processing industries. According to the Ghana Environmental Action Plan of 1994, the main producer of industrial pollutants by weight is the textile industry whose weight is estimated to account for30 % of the total amount of waste. The manufacture of food and beverages contributes 25 % while petro- leum refining and handling accounts for 20 %. Mineral exploitation and proc- essing are estimated to account for 10 %. Abrokwa- Ampadu (1986) estimates that at Tema, 80 % of wastewater discharged are from the textile industry. It has been estimated that about 60 % of all manufacturing industries are located in the Accra-Tema metropolis, which covers less than 1 % of the area of Ghana. Thus, this metropolis is the largest contributor of industrial pollution to the coastal waters. The main industries in the Accra-Tema metropolis are the tex- tile, food processing, soap factories, oil refinery and breweries.

6.1.3 Chemical pollution from agriculture Agricultural sources may include pesticides and fertilizers, which reach the coastal zone as land run-off and river discharge. Impacts of pollutants on water quality and aquatic organisms in the coastal waters have been studied by Amuzu (1976), Biney (1986) and more recently by Armah and Nyarko (1995) and Joiris et al., (1997). These studies showed that heavy metal levels have as yet not reached undesirable levels. The work of Joiris et al. (1997), however, has indicated the rising importance of pesticides in our coastal waters. Cockles (Anadara senilis) from the Benya lagoon were found to contain appreciable high levels of DDT to DDE ratios, which is a reflection of recent exposure. Aldrin and heptachlor were also detected in the cockles.

Mercury (Hg) levels in the cockles were low and below the maximum permis- sible level of 0.5 µg/g fresh weight of food stipulated by the World Health Or- ganisation (WHO). The maximum mercury content measured in A. senilis was 0.1 µg/g fresh weight. If a person eats more than 200 g of cockles in a day, this would convert to over 20 µg of Hg. There is, therefore, the need to monitor the

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 69

fish and other edible organisms from this lagoon and indeed others where the communities consume organisms from lagoons on daily basis.

6.1.4 Other chemical pollution Work carried out by the Department of Oceanography and Fisheries of the University of Ghana recently has shown that some population of marine snails or whelks. (T. haemastoma and T. nodosa) occurring on the rocky shores of the Ghana coast suffers from effects of tributyltin (TBT) pollution (Nyarko and Evans, 1997). The tributyltin compounds originate from antifouling paints used on boat hulls. TBT pollution is known to cause imposex, a condition in which male reproductive organs, including a penis and a sperm duct, become super- imposed on the female system. In severe cases it can lead to sterility and even promote death in female whelks. It was responsible for the decline in the popu- lations of similar whelks in southwest England (Bryan et al., 1986) and else- where in Europe in the 1980s (Harding et al., 1992). Further studies are needed for the entire coastline to establish the extent of this problem.

6.1.5 Oil spill events and threats Oil spill The probability and threats of marine oil spills derives from a variety of activities near shore or off shore:

• The delivery of crude oil and products to the refinery at Tema

• The delivery of petroleum products to Takoradi port

• Passing tankers emptying ballast water

• Ship accidents (collisions, explosions, fire, wrecking) with rupture of fuel tanks

• Failures in oil storage facilities near shore leaking oil to the sea

The Environmental Protection Agency (EPA) is the lead government agency in oil spill combat planning and response while the Ghana Navy has the responsi- bility for managing the response to an oil spill. On the whole, the national pre- paredness to combat oil spill is rather modest.

A National Oil Spill Contingency Plan was completed in 1996 but a lot more work has to be done to raise the level of awareness and competence of the vari- ous parties involved ensuring that high level of oil spill response preparedness is achieved and maintained.

Oil and gas explora- The occurrence of oil and gas emanations has been known in the onshore Tano tion basin for nearly a century. In the off shore area 3 important discoveries have been made, namely the Saltpond oil and gas fields, The North and South Tano oil and gas fields.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 70

Exploration and appraisal have been carried out in these fields over the past 15 years. For the time being there is however no commercial oil exploitation from off shore areas.

Petroleum development activities may increase the level of employment and expand community facilities. However, the impact on the coastal ecosystem may be negative. For example, it may give rise to increased environmental pol- lution from petroleum/oil sources and the waste arising from the expanded community.

Observed oil spills In Ghanaian waters no major oil spills have been ascertained but within recent years small spills have been reported to EPA.

6.2 Coastal Erosion Coastal erosion occurs both naturally and as a results of human influences along Ghana’s coastline. The degree of erosion depends on the location and geology of the area concerned. The well-known areas under serious erosion threats in Ghana are:

• The Keta Coast (from Dzelukofe to Blekusu)

• The Ada-Foah Beach (from the Volta Estuary to Otrokpe)

• The Labadi Beach (from Osu to Kpeshie Lagoon)

• The Nkontonpo Beach (between Sekondi and new Takoradi)

• The Axim shoreline

The rate at which the land is being lost to the sea in all these areas exceeds 1.5 m per annum, which is considered high. Other less known beaches whose rates of erosion are about the same are the Riviera Beach (between the Osu Castle and Mensah Guinea Beach).

The causes and patterns of erosion in Ghana have been examined by Armah, 1991; Anthonio, 1993 and Nai et al., 1993. The main causes of erosion are

i) sand and pebble winning

ii) hydrographic conditions like reinforcement of onshore waves due to wave refraction from adjacent headlands and

iii) disappearance of hydraulic groins at the mouths of fast flowing rivers due to dams constructed on them

Sand and pebble ex- Sand and pebble extraction from beaches for building purposes, although ille- traction gal, is a widespread practice and is a contributing factor in all the areas where shoreline erosion is critical.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 71

Reinforcements of Reinforcement of waves due to adjacent headlands and man-made structures waves like breakwaters seem to be the commonest cause of erosion with examples at Princess Town, Adjua, Nkontompo, Essipong, Komenda, Elmina, James Town beach, Tema and Prampram (Table 6.1).

Hydraulic groin ef- Examples of the hydraulic groyne effect could be found at Ada, Labadi, Bor- fect tianor and Kokrobite (Table 6.1).

The causes of erosion at Keta appear to be a combination of several factors in- cluding the geomorphology, hydrology, and angle of incident waves. Rates of erosion average 2 m per year in critical areas. In the worst hit area east of Keta, rates are even higher and sometimes up to 4 m per year.

Table 6.1. Examples of erosion along Ghana’s coast caused by reinforce- ments of waves and hydraulic groyne effect.

Cause of erosion Site Geographical coordinates Reinforcement of waves Princess Town 2° 80’ W, 4° 48’ N due to adjacent headlands Adjua 1° 48’ W, 4° 52’ N and man-made structures Nkontompo 1° 42’ W, 4° 59’ N like breakwaters Essipong 1° 42’ W, 4° 59’ N Komenda 1° 30’ W, 5° 30’ N Elmina 1° 30’ W, 5° 40’ N James Town beach 0° 13’ W, 5° 33’ N Tema 0° 00’ , 5° 55’ N Prampram 0° 2.5’ E, 5° 43’ N Hydraulic groin effect Ada 0° 37’ E, 5° 48’ N Labadi 0° 10’ W, 5° 33’ N Kokrobite 0° 21’ W, 5° 30’ N Bortianor

Not only does erosion and recession of the shorelines and beaches pose danger to dwellings near the shoreline, they also destroy the potential for tourism de- velopment along the coastline and fish landing sites.

In areas where erosion is threatening important settlements and infrastructure, a combination of gabions and boulder revetments have been employed to stop it. Only seven out of the 25 eroding areas are presently being protected through such means due to financial constraints (Armah, et al., 1998).

6.3 Over fishing The degradation of the fisheries, which includes the loss of species as well as declines in the sustainable harvest, is a concern in many coastal areas. Fishing is traditionally an important economic activity in Ghana; fish is also the most important source of protein in the diet.

The catches during the last five to ten years have not increased despite in- creased efforts. The increased effort can, for a large part, be linked to higher population coupled with preferences for fish as dietary source of protein. Hence

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 72

the catch per effort has dropped and this together with other data indicates that the present catches are close to or at the maximum that the fishery can sustain. Furthermore several types of fishery appear to suffer from overfishing and from the use of destructive fishing methods. Dynamite and poisons are used exten- sively in parts of the country and fishing using too small mesh sizes is also common throughout the entire coastal areas. The fisheries authorities have not been able to enforce the existing fishing regulations despite quite good knowl- edge at least at the central level.

While some fisheries degradation is caused by increases in fishing effort, in- creases in domestic and industrial pollution, and habitat loss from wetland and mangrove degradation, exacerbate the problem. There is, thus, a general decline occurring in the overall sustainability of the fishery.

6.4 Issues of Concerns in the Coastal Zone

6.4.1 Mangrove and wetland degradation The mangroves and wetlands in Ghana are threatened and steadily being de- stroyed as a result of :

• Fuelwood gathering

• Clearance for salt pans by the important salt extraction industry

• Urban pollution and urban encroachment.

These factors are strongly linked to population growth and economic activity. In particular, as the energy shortages continued to worsen within the coastal belt, fuel wood sources in the coastal savannah area have become depleted from over-exploitation. The coastal populations, especially the rural fishing commu- nities, are relying increasingly on mangrove stands as a fuel wood source for cooking and fish smoking. Consequently, many coastal mangroves are drying up after losing their vegetative cover. This affects their ability to sustain bio- logical diversity, biological resources and ecological processes.

The extraction of mangroves is usually done by cutting prop roots, branches and stems, a practice which when overdone does not encourage natural regen- eration. The result has been the gradual loss of mangroves at several localities especially around semi-closed lagoons along the dry coastal belt of the country. The practice is still in vogue in the Iture and Volta Delta areas and a commu- nity-based management programme needs to be put in place to salvage what is left. Extraction of mangrove for fuel wood at the Volta Delta is particularly alarming.

6.4.2 Sand and gravel mining in the coastal zone Sand and gravel mining on the beaches, although banned, continues to be the main supply source for construction of houses in the smaller towns and settle- ments. It is one of the causes of coastal erosion. Even in the big towns includ- ing Accra, pebbles mined from the beaches are openly sold. Quarrying occurs

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 73

at several sites along the coast. Often the larger ones are located in or near the main cities e.g., at Weija in Accra and Essipan near Sekondi. The exposed pits from the quarries have negative environmental and aesthetic impacts. Mere fill- ing with garbage from the municipality such as in Mallam and Gbawe in Accra proved inadequate as it has also created sanitary problems for the residents of the area.

Sand and gravel deposits currently being exploited in the Greater Accra Region (GAR) are mainly located in the vicinity of Amasaman, Tema, Dawhenya and Dodowa. Most of the licensed sand and gravel sites are located in or close to the Accra and Tema metropolitan areas due to the higher levels of industrializa- tion. There are potential deposits of about 25 to 30 million cubic meters in Amasaman and Dodowa. In the GAR there are 33 licensed sand and gravel sites, which cover about 176 hectares of land. The total daily production from the licensed sites is estimated to be 2500-3000 cubic meters.

In the Western Region, the areas being exploited are mainly along the beach in Atube, Princess Town, Pampuni, Adwoa, Funko and inland in the vicinity of Bronyikom and Yabiw. Most licensed miners are located close to the Sekondi- Takoradi area. There are 36 licensed sand and gravel sites in the Western Re- gion and together they cover 38 hectares of land. Daily production from these sites is estimated to be 2500-3000 cubic meters. Apart from these licensed sites, the region has potential deposits in Asake and Butre with an estimated 20-25 million cubic meters.

Sand and gravel winning activities disturb riverine estuaries by increased sedi- mentation and high concentration of dissolved and suspended solids, which cre- ates a situation that endangers marine life. Mangroves along the Pra River are affected by mining activities both along the coast as well as mining further inland. Sand mining along the beaches also affects the water table and further exacerbates the scarcity of water, which is a major problem faced by coastal communities. Sand winning destroys coastal biodiversity and poses threats to marine habitat. Fish larvae as well as economically important varieties of shell- fish depend on the maintenance of coastal habitat including estuaries. Unregu- lated mining activities pose serious threats to valuable ecosystems, which are home to several different species both on land and at sea. The destruction of fauna and flora along the coastline due to mining activities deprives local peo- ple of their livelihoods. Sacred areas, artefacts and historical sites situated within the coastal zone are threatened posing problems to the growth of the tourist industry.

6.4.3 Impact of inland drainage on coastal lands and waters Inland drainage in Ghana is dominated by the Volta system, which apart from its large tributaries, includes the Volta Lake and the Kpong headpond. Outside of this system, some major rivers including the Tano, Ankobra, Pra and Densu drain into the sea through coastal lagoons and estuaries. In Ghana the negative effects of inland drainage on coastal lands and waters have arisen mainly from the impoundment of rivers. Also surface waters may carry into the coastal zone pollutants originating from point sources such as municipal and industrial

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 74

drains or diffuse sources including land runoff containing soil, pesticides and fertilizers.

6.4.4 Endangered species Marine turtles are listed as endangered and are among the marine animals under protection by law in Ghana (L.I 685). The marine turtles, which were once quite common visitors to the beaches of Ghana, have greatly reduced their numbers due to a number of factors:

• People capture and kill them for their meat and collect their eggs

• Pigs, dogs and other animals along the coast also dig out turtle eggs and eat them

• The removal of sand from the beaches for construction purposes is a serious threat to sea turtle nesting habits. High tides very often wash away the eggs because of the sand winning practices in most areas

• Plastic rubbish on the beaches poses a major threat to the turtles be- cause they often mistake plastic bags for jellyfish and swallow them. A few turtles have been found dead and washed ashore as a result of this

According to Ghanaian law capture, killing and collection of turtle eggs is an offence punishable by a fine, or imprisonment or both. Despite this slaughter of female adult turtles and the collection of their eggs continues and may in fact lead to the extinction of these turtles along the coast of Ghana.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 75

7 References Ababio, S.D. (2001). The population parameters, food habits and physico- chemical environment of three cichlid species in the south-western sector of the Keta lagoon. M.phil. Thesis. University of Ghana, Legon. 95pp.

Abrokwa-Ampadu R. (1986). Marine Pollution in Ghana Coastal Water. Annex 8 to the Report of The Ghana National Seminar on Marine Pollution, Control and Response. IMO. London.

Afoakwa,S.N, D. Agbodaze and C.A. Abrahams (1988). Microbiological Qual- ity of the Coastal Waters of Ghana: A Bacteriological Appraisal. GNC/IOC Seminar on the Conservation and Utilisation of Marine Resources 5-9th Sep- tember 1988, Accra.

Akpati, B.N (1975). Source and Dispersal of Holocene Sediments on the Con- tinental Shelf of Ghana, West Africa. Research Report of UNESCO. Contract SCARP600.874, 44 p.

Allersma, E. and Tilmans, W.M.K. (1993). Coastal conditions in West Africa: a review. Ocean and Coastal management 19, p. 199-240.

Amuzu (1996). A survey of the Water Quality of Korle Lagoon. Architectural and Engineering Services Corporation. September 1976, 28 pp.

Anquandah K.J (1999). Castles and Forts of Ghana. Ghana Museums & Monuments Boards Book.

Anthonio, S.L (1993). Sea-Level Rise and Coastal Erosion in Ghana. Report of the National Workshop on Climate Change and its Impact on Water, Oceans, Fisheries and Coastal Zones. Ghana National Committee for the International Hydrographical Programme (IHP). WRRI/CSIR, Accra.

Armah, A.K. (1991). Coastal erosion in Ghana; causes, patterns, research needs and possible solutions Coastal Zone 91: 2463-2473.

Armah, A.K. (1993a) Coastal Wetlands of Ghana. Coastal Zone 93. 13-322.

Armah, A.K. (1993b). Coastal Wetlands of Ghana. Coastal Zone 93: 313-322. American Society of Civil Engineering, New York.

Armah, A.K (2004) Unpublished manuscript.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 76

Armah, A.K. & Amlalo, D.S (1998). Coastal Zone Profile of Ghana. Gulf of Guinea Large Marine Ecosystem Project. Ministry of Environment, Science and Technology, Accra, Ghana, 111 p.

Armah, A.K. and E. Nyarko (1995). Preliminary Studies on the Amenability of Three Marine Intertidal Gastropods to Biomonitoring of Heavy Metal Pollution in Ghanaian Coastal Waters. In: Proceedings of the Joint 19th Ghana Science Association/15th West African Science Association Biennial Conference, Sep- tember 18-22. University of Cape Coast, Ghana.

Bannerman, P.O., Koranteng, K.A. & Yeboah, C.A. (2001). Ghana canoe frame survey. Information Report No. 33. Marine Fisheries Research Division

Bassindale R (1961). On the marine fauna of Ghana. Proceedings of the Zoo- logical Society of London 137. 2 pp.481-510.

Binet, D.E. E. Marchal and O. Pezennec (1991). Sardinella aurita de Cote d´Ivoire et du Ghana: fluctuations halienthiques et changements climatiques. In: P. Cury et C. Roy (eds). Pêcheries Ouest Africaines: varibilité, instabilité et changement. Editions de l`ORSTOM.

Biney, C.A. (1996). The State of Pollution of the West and Central African Ma- rine Environment - Aspects of the Ghanaian Situation. Institute of Aquatic Bi- ology, Achimota. September 1986, 24 p.

Boughey A.S. (1957). Ecological studies of tropical coastlines of the gold coast, West Africa. Journal of ecology vol. 45, pp. 665-687.

Bruun, P. (1962). Sea Level Rise as a cause of shore erosion. J. Waterways Harbors Division, ASCE 88, pp. 117 – 130.

Buchanan J.B (1958). The bottom fauna communities across the continental shelf off Accra Ghana. Proceedings of the Zoological Society of London 130 (1) 1958.

Carr, T. and Campbell, C.L. (1995). A management strategy outline for marine turtle conservation in Ghana. Project Report submitted to the Department of Game and Wildlife, Ghana.

Dickson, K.B. and Benneh G. (1980). A new geography of Ghana. Langmar 173 p.

Doi B.A. (1984). Catalogue of small-scale fishing gear of Ghana, CECAF/ECAF Series 84/31 (En), FAQ Rome.

EC (1989). Coastal erosion in the Bight of Benin – national and regional as- pects. Report on Expert Findings, 370 pp.

EPC (1990). Coastal Zone Indicative Management Plan. Environmental Protec- tion Council, Accra, Ghana.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 77

Eckert, K.L. (1993). The biology and population status of marine turtles in the North Pacific Ocean: Prepared for NMFS, NOAA, Honolulu Laboratory, SWFSC, Honolulu, Hawaii.

Edwards, R. A., Whitmarsh, R. B. and Scrutton, R. A. (1997). Synthesis of the crustal structure of the transform continental margin off Ghana, northern Gulf of Guinea. Geophysical Marine Letters 17, 12 – 20.

EPC (1990). Coastal Zone Indicative Management Plan. Environmental Pro- tection Council, Accra, Ghana.

EPA (1998/1999). Environmental Sensitivity Map of the Coastal Zone of Ghana. Preliminary Report. Environmental Protection Agency, Accra.

FAO (1980) Food Balance Sheets. Rome.

FAO (1992). Report of the ad hoc Working Group on the Coastal Pelagic Stocks of the Western Gulf of Guinea (Côte d'Ivoire, Ghana, Togo, Benin), held at the Centre de Recherché Océanographique, Abidjan, Côte d'Ivoire, 10– 16 December 1990. CECAF/ECAF/Series. N° 91/56. Rome, FAO. 1992. 153 p.

Fontaine, B., Janicot, S. and Roucou, P. (1999). Coupled ocean-atmosphere surface variability and its climate in the tropical Atlantic region. Climate Dy- namics 15, 451 – 473.

Garzoli, S. L. and Katz, E. J. (1983). The forced annual reversal of the Atlantic North Equatorial Counter Current. Journal of Physical Oceanography 13, 2082.

deGraft Johnson, K.A.A (1991). Ecosystems and Vegetation. In: Coastal man- agement plan for Accra, Vol. 5. Specialist papers. Environmental Management Associates and Mandis Roberts Consultants, 39pp.

Gauld D.T. and J. B. Buchanan (1956). The fauna of sandy beaches in the Gold Coast. OIKOS 7: II, Copenhagen 1956.

Ghana Statistical Service (March 2002). 2000 Population & Housing Census.

G.T.B (1995) Tourism statistics, Ghana Tourist Board, Accra.

Harding, M.J.S, S.K. Bailey S.K & I.M. Davies (1992). TBT Imposex Survey of the North Sea. Department of the Environment UK (Contract PECD 7/8/24).

Ingham, M.C. (1970). Coastal upwelling in the north-western Gulf of Guinea. Bulletin of Marine Science, 20, 1 – 34.

Irvine F.R. (1947). The Fishes and Fisheries of the Gold Coast. University Press, Cambridge.

John, D.M. (1986). Littoral and Sub-Littoral marine vegetation: In: G.W. Law- son (Ed.). Plant ecology of West Africa. John Wiley and Sons Ltd.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 78

John, D.M and Lawson, G.W. (1990) Review of Mangrove and Coastal Eco- system in West Africa and their Possible Relationship. Est. Coast. Shelf Sci. 31: 505-515

Joiris, C.R., F.A. Otchere, M.I. Azokwu and I.B. Ali (1997). Total and Organic Mercury and Organochlorides in a Bivalve from Ghana and Nigeria. In: S.M. Evans, C.J. Vanderpuye and A.K. Armah (eds). The Coastal Zone of West Af- rica: Problems and Management. Proceedings of an International Seminar on ICZM in Accra Ghana, 25-29 March, 1996. Penshaw Press UK.

Jones, A.E. (1970). Report on the offshore fishery for shrimp (Penaeus duora- rum) in Ghana. Unpublished.

Koranteng K.A. (1995a). Ghana Coastal Wetlands Management Project. Envi- ronmental Baseline Studies. Muni-Pomadze Ramsar Site. Fisheries. Prepared for the Ghana Wildlife Department, Government of Ghana.

Koranteng K.A. (1995b). Ghana Coastal Wetlands Management Project. Envi- ronmental Baseline Studies. Sakumo Ramsar Site. Fisheries. Prepared for the Ghana Wildlife Department, Government of Ghana.

Koranteng K.A. (1995c). Ghana Coastal Wetlands Management Project. Envi- ronmental Baseline Studies. Densu Delta Ramsar Site. Fisheries. Prepared for the Ghana Wildlife Department, Government of Ghana.

Kwei, E.A. (1977). Biological, Chemical, and Hydrological Characters of Coastal Lagoons of Ghana, West Africa. Hydrobiol. 56: 157-174.

Lawson, G.W. (1957) Rocky Shore Zonation on the Gold Coast. Journal of Ecology, 44: 153-170

Lincoln D, C. Fishpool and M.I. Evans (2001). Important Bird Areas in Africa and associated islands. Priority sites for conservation. Newbury and Cam- bridge, UK: Pisces Publications and BirdLife International (Birdlife Conserva- tion series No 11.

Longhurst, A. R (1962). A review of the oceanography of the Gulf of Guinea. Bulletin IFAN (Series A), 24: 633-663.

Ly, C.K. (1980) The role of the Akosombo Dam on the Volta River in causing coastal erosion in central and eastern Ghana (W. Africa). Marine Geology 37:323-332.

Marchal, E. and Picaut, J. (1977). Repartition et abundance evaluees par echo- integration des poisons du plateau ivoiro-ghaneen en relation avec les upwel- lings locaux. Journal Recherche Oceanographie 2, 39 -57.

Marine Fisheries Research Division (2003). 1986-1995 Report on the Research and utilisation Branch (Fisheries Department) now renamed Marine Fisheries Research Division Directorate. Ministry of food and agriculture.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 79

Márquez, M. R. (1990). FAO species catalogue. Vol. 11: Sea turtle of the world. An notated and illustrated catalogue of sea turtle species known to date. FAO Fisheries Synopsis No. 125, vol. 11, FAO , Rome pp 81.

Mensah, M.A.(1991).The influence of Climatic Changes on the Coastal Ocean- ography of Ghana. In: P.Cury and C. Roy (Eds). Pecheries Ouest Africaines: Variabilité, Instabilité at Changement. Editions de l`ORSTOM.

Merle, J. and Arnault, S. (1985). Seasonal variability of the tropical South At- lantic and linkages to the Pacific. Geophysical Research Letters 13, 1039 – 1092

Moore, D. W. , Hisard, P., McCreary, J. P., Merle, J., O’Brien, J.J., Picaut, J., Verstraete, J. M. and Wunsch, C. (1978). Equatorial adjustment in the eastern Atlantic ocean. Geophysical Research Letters 5, 637 – 640.

Nai, G.G., J.A.Addo and J. Wellens-Mensah (1993). Coastal Erosion Points in Ghana and their Protection p 189-202. Report of the National Workshop on Climate Change and its Impacts on Water, Oceans, Fisheries and Coastal Zones. Pub: Ghana National Committee for the International Hydrological Pro- gramme (IHP) WRRI/CSIR, Accra.

Ntiamoa-Baidu, Y. and Gordon, C. (1991). Coastal wetlands management plan: Ghana. Unpublished report to the World Bank, Department of Zoology, Uni- versity of Ghana, Accra.

Ntiamoa-Baidu, Y. and Hepburn, I.R. (1988). Wintering waders in coastal Ghana RSPB Cons.Review 24: 46-62.

Overfield, D.A., M. Adam, N. Ghartey, R. Arthur, R. Duhamel and N. Wil- loughby (1997).The Economic and Social Consequences of Cape Saint Paul Wilt Disease in Ghana and its Implications for Coastal Zone Management Is- sues. In: S. M Evans, C. J. Vanderpuye and A.K. Armah (eds). The Coastal Zone of West Africa: Problems and Management: Proceedings of an Interna- tional seminar on ICZM in Accra, Ghana, 25-29 March 1996. Penshaw Press, UK.

Pauly D (1976). The biology, fishery and potential for aquaculture of Tilapia melantotheron in a small West African lagoon. Aquaculture 7: 33-49.

Piersma, T. and Ntiamoa-Baidu (1995). Waterbird Ecology and the Manage- ment of Coastal wetlands in Ghana. Netherlands Inst. Sea. Res. No. 6. 1105p.

Research and utilisation Branch Tema, Ghana (1990). Report for the triennium 1983-1985 on the Research and Utilisation Branch of the Fisheries Department.

Richardson, P.L. (1984). Moored current meter measurements in the Atlantic North Equitorial Counter Current during 1983. Geophysical Research Letters 11, 749 – 752.

Volume II – Coastal Environment, October 2004

Environmental Sensitivity Map for Coastal Areas of Ghana 80

Sackey, I.E. Laing and J.K. Adomako (1993). l’ETAT Actuel des Mangroves du Ghana. In Diop. E.S. (Ed), Conservation et utilization Rationnelle des forets de Mangrove de I’Amerique Latine et de I’Afrique. Vol. 2 Dakar, 20-22 Janu- ary 1993 ITTO/ISME Project PD114/90(F).

Sackey, I., J.K. Adomako and E. Laing (1997). Regeneration and Litter Pro- duction Studies in Two Contrasting Mangrove Ecosystems in Ghana. In: S.M. Evans, C.J. Vanderpuye and A.K. Armah (eds.) The Coastal Zone of West Af- rica: Problems and Management. Proceedings of an International Seminar on ICZM in Accra, Ghana, 25-29 March, 1996. Penshaw Press, UK.

Saenger, P and M.F. Bellan (1995) The mangrove vegetation of the Atlantic Coast of Africa-a review. Laboratoire d’Ecologie Terreshre (UMR 9964) Uni- versite de Toulouse, France. 96 p.

Schneider, W. (1990). FAO species identification sheets for fishery purposes. Field guide to the commercial marine resources of the Gulf of Guinea. FAO, United Nations, Rome.

Shenker, J.M., Dankwa, H.R., Junda, L., Ofori-Danson, P.K. and Ntiamoa- Baidu, Y. (1998). Fisheries of Keta and Songor Lagoons. Coastal Wetlands Management Projects. Ghana Wildlife Dept. 59 p

Sætersdal, G.; Bianchi, G.; Strømme, T.; Venema, S.C. (1999) The DR. FRIDTJOF NANSEN Programme 1975–1993. Investigations of fishery re- sources in developing countries. History of the programme and review of re- sults. FAO Fisheries Technical Paper. No. 391. Rome, FAO. 1999. 434p.

Taylor, C. J (1960). Sunecology and Silviculture in Ghana. Thomas Nelson and Sons Ltd, UK.

Tsidzi K.E.N, M.A. Akoto and Y. Iddrisu (1995) Geological Hazards Mitiga- tion in Ghana: The State of the Art: Ghana Mining Journal. Vol. 1 Nos 1 & 2

Verstraete, J.M. (1970). Etude quantitative de l’upwelling sur le plateau continental ivoirien. Document Scientifique C.R.O. 1, 1 – 17.

WB and EPA, 1996. Towards an Integrated Coastal Zone Management Strat- egy for Ghana, World Bank and The Environmental Protection Agency, Ghana, 137 pages.

Wiafe, G.( 2002). Spatial and temporal dynamics of plankton communities in the Gulf of Guinea ecosystems. PhD. Thesis. University of Ghana, Legon, 188pp.

Volume II – Coastal Environment, October 2004