Wednesday 26 June 2013

CHANGING PATTERN OF GAMBIA’S POPULATION DISTRIBUTION 1963 TO 2003

CHANGING PATTERN OF GAMBIA’S POPULATION DISTRIBUTION 1963 TO 2003



ABSTRACT
The stresses of climate change and explosive state of demographic transition in developing countries like the Gambia have led to the transformation of their economic activities which initiated redistributive tendencies in their spatial patterns of employment opportunities. As a result, the spatial distributional pattern of population in these countries is also undergoing changes. Analysis of these changes is useful for administrative and socio economic planning in addressing issues like determining the electoral constituencies, the provision of education, health and other social facilities,  waste disposal and management, and more importantly for devising coping strategies for the adverse effects of climate change on fragile ecosystems and vulnerable groups. It is in this context that this paper looks at the changes that have taken place in the distribution of Gambia’s population from 1963 to 2003 based on data of the four censuses conducted during the period. Although the first country wide census in The Gambia took place as early as 1881, it was from 1963 that censuses of good quality have been conducted on defacto basis. Therefore, 1963 census data serve as the reference point for analysis of the Gambia’s population characteristics.

KEY WORDS: The Gambia, spatial, distributional pattern, change, analysis, census, data


INTRODUCTION
 One of the most important uses of the population census data is the information it provides about the population settlement pattern in a geographic area. It is pertinent, therefore,  to examine the changes in the pattern of spatial distribution of the Gambia’s population as revealed by the data of the four censuses that took place from 1963 to 2003 using the administrative region of a local government area (LGA) as the unit of analysis.

The concept of distribution of a population refers to the spatial pattern in which the population finds its location. Thus, the concern of spatial distribution is the pattern of spread which may be linear, dispersed, nucleated, or agglomerated among others. There are several methods of describing the spatial distribution of a population; among them the percentage distribution is the simplest which indicates the percentage of a population in a given class of geographical area. The other simple method is the rank order in which the geographical areas of a given class are listed in a rank for a census year to enable comparison between different census years in order to reveal the trend of population growth overtime. Besides, the median point, the mean point (the centre of population), the point of minimum aggregate travel, and the point of maximum population potential are used by population geographers to measure population distribution. However, in this analysis the simple methods of percentage distribution and rank order are used to examine the change in the Gambia’s population distribution from 1963 to 2003. Besides, Lorenz curve is used to compare the country’s population distribution pattern for 1963 and 2003.

Physical Features and Administrative Divisions
Situated between latitude 13N and 14N, and between longitude 14W and 17W on the bulge of the western coast of Africa along the Atlantic Ocean, with a total area of 11, 420 km2 and occupying a land area of 10, 690km2 (Jaiteh & Saho, 2006), the Gambia is the smallest country on mainland Africa. The country is surrounded by Senegal, its only neighbor, on all sides except the west which opens into the Atlantic Ocean.

The climate of the country is conditioned by its tropical latitude and the seasonal migration of the Inter Tropical Convergence Zone (ITCZ) – the line of low pressure at which the hot dry continental wind from the northeast meets the moist oceanic southwest wind to produce precipitation. Hence, the climate is characterized by a distinct dry season between November and May when the position of the ITCZ shifts towards the coast and the northeast trade winds, locally referred to as Harmattan, became dominant; and a wet season from June to October when the low pressure centre migrates to the interior thereby bringing the area under the influence of the southwest monsoons from the Atlantic. The influence of the Cool Canary Currents in this part of the Atlantic modified the coastal climate to a sub – tropical type which makes the climate of the area more conducive than the interior of the country which has a typical tropical climate of the Sudanic type.

Map 1: Elevation Map of the Gambia Adapted From Jaiteh & Sarr 2011

The River Gambia, after which the country is named, dominates the topography (see map 1) as it flows through the entire length of the country in east – west direction and its floodplains which are flanked by low laterite hills form the width of the country which is about 48km along the coast and 24km in the interior. Hence, the country is generally flat with more than 48% of the total land area below 20metres in elevation (Jaiteh & Saho, 2006). The river is politically significant too as its tributaries, locally known as bolongs, form the natural boundaries of most of the countries administrative regions.

The Gambia is divided into eight local administrative divisions which are designated as Local Government Areas (LGAs) and they form the basic unit of analysis for this paper because the country’s census data are aggregated according to this geographic class of LGA. The eight Local Government Areas comprise the city of Banjul (the seat of Government), the Kanifing Municipality, and the six local government areas of Brikama, Mansa Konko, Kerewan, Kuntaur, Janjangbureh and Basse. Each of these local government areas corresponds with an administrative region except for Janjangbureh and Kuntaur which jointly formed the Central River Region. The LGAs of Brikama, Mansa Konko, Kerewan, and Basse correspond with the West Coast Region, Lower River Region, North Bank Region and Upper River Region respectively.

Changes in Population Distribution by Census Year
Since 1963 census data is the bench mark for the study of this paper, it is important to analyse the pattern of distribution of the Gambia’s population in 1963 with respect to the land area.

Table 1: Area, Population & Density by Local Government Area (LGA) in 1963
Local Government Area (LGA)
Land Area (sq. km)
% of Total Land Area
Population in 1963
% of Total Population
Population Density Persons/km2
Banjul
12
0.1%
27 809
8.8%
2317
Kanifing
76
0.7%
12 208
3.9%
161
Brikama
1 764
16.5%
55 393
17.6%
31
Mansa Konko
1 618
15.1%
34 227
10.8%
21
Kerewan
2 255
21.1%
63 045
20.0%
28
Kuntaur
1 467
13.7%
29 003
9.2%
20
Janjanbureh
1 428
13.4%
35 752
11.3%
25
Basse
2 070
19.4%
58 049
18.4%
28
The Gambia
10 690
100%
315 486
100%
30
Sources: GoTG 1996, and Jaiteh & Saho 2006

The Gambia, as revealed by Table 1, had a total population of 315, 486 people in 1963. From among the various Local Government Areas, Kerewan was the most populated accounting for 20.0% of the Gambia’s total population in 1963; and Kanifing was the least populated, with only 3.9% of the country’s total population as shown in both Table 1 and Figure 1.

Figure 1: LGAs by Area and Population Size - 1963
Comparing the size of each LGA as a percentage of the total land area of The Gambia with its total population as a percentage of The Gambia’s 1963 population, as shown in figure 1, revealed a fairly even distribution. For instance, Kerewan Local Government Area accounted for 21.1% of the total land area and 20.0% of the total population. Similarly Basse LGA with 19.4% of the total land area accounted for 18.4% of the total population; and Brikama LGA with 16.5% of the total land area accounted for 17.6% of the 1963 total population. The pattern is not markedly different for Janjanbureh LGA with 13.4% of the total land area accounting for 11.3% of the total population. On the other hand, the LGAs of Mansa Konko and Kuntaur had significant differences between their sizes of land area (15.1% and 13.7%) and proportion of total population (10.8% and 9.2% respectively). The same is true for the LGAs of Banjul and Kanifing which accounted for larger proportion of population (8.8% and 3.9%) than land area (0.1% and 0.7%). It is intriguing to observe that the LGAs of Banjul, Kanifing and Brikama accounted for larger percentage of population than area whereas the remaining LGAs had larger percentage of area than population.

As shown in both Table 1 and Figure 1, the most populous LGA in 1963 was Kerewan, Followed by Basse, then Brikama, Janjanbureh, Mansa Konko, Kuntaur, Banjul and Kanifing. This matched fairly well with the ranking of LGAs according to size which has Kerewan as the largest, followed by Basse, then Brikama, Mansa Konko, Kuntaur, Janjanbureh, Kanifing and Banjul.

Since the Local Government Areas have very large differences in their areal extent, the density which deals with the ratio between the size of population and the area portrays a better picture of the population – resource relationship. The density of population is usually computed as population per square kilometer (km2) of land area. Different types of densities like arithmetic, physiological or nutritional, agricultural, and economic, are devised for utilization in different situations with the aim to arrive at a better indicator for the population resource relationship. In this paper the analysis of density is confined to the simple arithmetic density which refers to the ratio of population of a given geographical unit to the area occupied by that unit.

 As is evident from Table 1, in 1963 the Gambia had an average density of 30 persons per km2, the sharp differences between LGAs like Banjul (2,317 persons/km2) and Kuntaur (20 persons/km2) notwithstanding. From among the various LGAs, Banjul (2,317 persons/km2), Kanifing (161 persons/km2), and Brikama (31 persons/km2) had densities more than the national average. The remaining LGAs like Kerewan (28 persons/km2), Basse (28 persons/km2), Janjanbureh (25 persons/km2), Mansa Konko (21 persons/km2), and Kuntaur (20 persons/km2) had densities below the national average of 30 persons/km2. It is interesting to note that the densities for the large LGAs of Kerewan, Basse and Brikama were very close to the national average.


Table 2: Area, Population & Density by Local Government Area (LGA) in 1973
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1963
Population in 1973
Decadal % Increase
% of 1973 Total Population
Population Density (Persons/km2)
Banjul
12
27 809
39 179
41%
7.9%
3265
Kanifing
76
12 208
39 404
223%
8.0%
518
Brikama
1 764
55 393
91 013
64%
18.4%
52
Mansa Konko
1 618
34 227
42 447
24%
8.6%
26
Kerewan
2 255
63 045
93 388
48%
18.9%
41
Kuntaur
1 467
29 003
47 669
64%
9.7%
32
Janjanbureh
1 428
35 752
54 232
52%
11.0%
38
Basse
2 070
58 049
86 167
48%
17.5%
42
The Gambia
10 690
315 486
493 499
56%
100%
46
Sources: GoTG 1996, and Jaiteh & Saho 2006

According to table 2, the 1973 census revealed a 56% increase in the Gambia’s total population from 315, 486 people in 1963 to 493, 499 in 1973. It implied an addition of 178, 013 people within a decade. From among the various LGAs, as shown in figures 2 & 3, Kanifing recorded the highest increase in its share of population which had more than tripled from 12, 208 to 39, 404 people. It registered a whopping 223% increment in its population during the 1963 – 1973 inter census period. Consequently, its share of the total population more than doubled from 3.9% in 1963 to 8.0% in 1973. Next in line were Brikama and Kuntaur LGAs. The population of Brikama LGA rose from 55, 393 people to 91, 013 registering 64% increment in the inter census period. Similarly, Kuntaur Local Government Area’s population had increased by 64% from 29, 003 to 47, 669 people.

Figure 2: LGAs by Population Size, 1963 & 1973


In contrast, the population of Mansa Konko increased marginally from 34, 227 in 1963 to 42, 447 in 1973; and so, it registered only 24% increment during the inter census period. Hence, the LGA recorded a decline in its share of total population from 10.8% to 8.6%. Mansa Konko was followed by Banjul which recorded 41% increment from 27, 809 to 39, 179 people thereby becoming the least populated LGA in 1973, replacing Kanifing. The other LGAs with growth rates below the national average of 56% were Kerewan, the population of which grew from 63, 045 to 93, 388 people and it recorded 48% increment, Basse also recorded 48% increment as its population rose from 58, 049 to 86, 167 people. Janjanbureh’s population grew from 35, 752 to 54 232 persons and it registered 52% increment.





Figure 3: LGAs Population as Percentage of 1963 & 1973 Population

 The 1973 census revealed a decrease in the share of population of all the LGAs except for Kanifing, Brikama and Kuntaur. Thus, the rank order of the LGAs according to population got slightly modified with Brikama replacing Basse as the second most populated LGA after Kerewan. Similarly Kuntaur replaced Mansa Konko as the fifth most populated LGA and Banjul was relegated to the bottom replacing Kanifing which took over its position as the seventh most populated LGA.

The Gambia in the decade 1963 – 73 had registered an increase of 16 persons in the average density of her population from 30 /km2 to 46 /km2. Among the various LGAs, Banjul had maintained its distinction of having the highest density of population (3, 265). It was followed by Kanifing which had more than tripled its density from 161 to 518. Brikama with a density of 52 persons/km2 followed Kanifing. At the other end of the scale was Mansa Konko (26) which replaced Kuntaur as the LGA with the lowest density in the country. It was followed by Kuntaur (32), Janjanbureh (38), Kerewan (41) and Basse (42).

Table 3: Area, Population & Density by Local Government Area (LGA) in 1983
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1973
Population in 1983
Decadal % Increase
% of 1983 Total Population
Population Density (Persons/km2)
Banjul
12
39 179
44 188
13%
6.4%
3682
Kanifing
76
39 404
101 504
158%
14.8%
1336
Brikama
1 764
91 013
137 245
51%
20.0%
78
Mansa Konko
1 618
42 447
55 263
30%
8.0%
34
Kerewan
2 255
93 388
112 225
20%
16.3%
50
Kuntaur
1 467
47 669
57 594
21%
8.4%
39
Janjanbureh
1 428
54 232
68 410
26%
9.9%
48
Basse
2 070
86 167
111 388
29%
16.2%
54
The Gambia
10 690
493 499
687 817
39%
100%
64
Sources: GoTG 1996, and Jaiteh & Saho 2006

According to the 1983 census, as shown in table 3, the Gambia’s population grew from 493, 499 people in 1973 to 687, 817 in 1983 revealing a 39% increase which was lower than the 1963 – 73 inter decadal increment of 56%. However, in absolute terms, it indicated an addition of 194, 318 people within the decade which was more than the178, 013 people added in the previous decade.




Figure 4: LGAs by Population Size, 1973 & 1983
From among the LGAs, as shown in figure 4, only Kanifing and Brikama recorded growth rates higher than the national average of 39%. Kanifing had maintained its distinction of having the highest growth rate of 158% by more than doubling its population from 39, 404 in 1973 to 101, 504 people in 1983. Hence, it increased its share of the total population from 8.0% in 1973 to 14.6% in 1983 as shown in figure 5; which made it the fourth largest populated LGA for that census year. Brikama also maintained its position as the second fastest growing LGA with a growth rate of 51% from 91, 013 in 1973 to 137, 245 people in 1983. Consequently, it became the most populous LGA in 1983 accounting for 20% of the country’s total population.

Figure 5: LGAs Population as Percentage of 1973 & 1983 Population

From among the LGAs with growth rates less than the national average of 39% during the decade, Banjul registered the lowest growth rate of 13% in 1983 followed by Kerewan (20%), Kuntaur (21%), Janjanbureh (26%), Basse (29%) and Mansa Konko (30%) in that order.

The trend of change observed in 1983 was similar to that of 1973, except that Kuntaur had joined the LGAs with growth rates lower than the national average of 39%. That made Kanifing and Brikama to be the only LGAs with growth rates more than the national average. As a result, the rank order of the LGAs according to population size got modified with Brikama replacing Kerewan as the most populous which followed in second place, then Basse (which closely followed Kerewan), Kanifing (which moved up from seventh position), Janjanbureh, Kuntaur,  Mansa Konko and Banjul.

The 1983 census revealed an average density of 64 persons per km2 for the country, implying an addition of 17 people to the country’s density of 47 in 1973, which was almost the same as the number added in the previous decade. From among the LGAs Banjul maintained the highest with a density of 3, 682 persons per km2 followed by Kanifing which had more than doubled its density from 518 persons per km2 in 1973 to 1, 336 persons per km2 in 1983. Brikama followed with a density of 78, for the LG As with densities more than the national average of 64. For the LGAs with densities less than the national average, Mansa Konko maintained the lowest position with 34 persons per km2, followed by Kuntaur (39), Janjanbureh (48), Kerewan (50) and Basse (54) in that order.

Table 4: Area, Population & Density by Local Government Area (LGA) in 1993
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1983
Population in 1993
Decadal % Increase
% of Total Population
Population Density (Persons/km2)
Banjul
12
44 188
42 326
-4%
4.1%
3527
Kanifing
76
101 504
228 214
125%
22.0%
3003
Brikama
1 764
137 245
234 917
71%
22.6%
133
Mansa Konko
1 618
55 263
65 146
17.9%
6.3%
40
Kerewan
2 255
112 225
156 462
39.4%
15.1%
69
Kuntaur
1 467
57 594
67 774
17.7%
6.5%
46
Janjanbureh
1 428
68 410
88 247
29%
8.5%
62
Basse
2 070
111 388
155 059
39.2%
14.9%
75
The Gambia
10 690
687 817
1 038 145
51%
100%
97
Sources: GoTG 1996, and Jaiteh & Saho 2006

The 1993 census, as shown in Table 4, revealed that the Gambia had a population of 1, 038, 145 people and it registered 51% growth rate during the inter census period. It pointed out an addition of 350, 328 people to the country’s population within a decade; a number which was more than the Gambia’s 1963 total population of 315, 486 people and almost doubled the 178, 013 persons added in the decade before.

Figure 6: LGAs by Population Size, 1983 & 1993
                 

From among the LGAs Kanifing and Brikama continued to register growth rates higher than the national average.  As shown in table 4 & figure 6, Kanifing’s population jumped from 101, 504 in 1983 to 228, 214 people in 1993 registering 125% increment in its population during the decade. Accordingly, as shown in figure 7, its share of the total population soared from 14.8% in 1983 to 22.0% in 1993 making it the second most populous LGA in the country. Characteristically, Brikama followed as the second fastest growing LGA with a growth rate of 71%. Having increased its population from 137, 245 in 1983 to 234, 917  people in 1993 which represented 22.6% of the country’s total population for that year, Brikama continued to be the most populous LGA; although, closely followed by Kanifing as shown in figure 7.




Figure 7: LGAs Population as Percentage of 1983 & 1993 Population


The rest of the LGAs, as usual, registered growth rates less than the national average of 51% with Banjul (which for the first time recorded a negative growth rate of -4%) at the end of the scale. Banjul was followed by Kuntaur (17.7%), Mansa Konko (17.9%), Janjangbureh (29%), Basse (39.2%) and Kerewan (39.4%) in that order. Thus, the trend of change observed in 1993 was identical to that of 1983 as Kanifing continued to move swiftly up the rank by relegating both Kerewan and Basse to occupy second position after Brikama. Therefore, Brikama continued to be the most populous LGA in 1993, closely followed by Kanifing, then Kerewan, Basse, Janjanbureh, Kuntaur, Mansakonko and Banjul.

The 1993 census revealed an average density of 97 persons per km2 for Gambia as a whole, implying an addition of 33 persons to the country’s density of 64 in 1983.  Thus, the decade witnessed the highest increase in the country’s density which almost doubled the 17 people increment of the previous decade. From among the LGAs, Banjul continued to maintain having the highest density although its density declined slightly from 3,682 persons per km2 in 1983 to 3,527 persons per km2 in 1993. Banjul was closely followed by Kanifing which has more than doubled its density from 1,336 persons per km2 in 1983 to 3,003 persons per km2 in 1993. Brikama, as usual, followed Kanifing with a density of 133 persons per km2 in 1993; up from 78 persons per km2 in 1983 implying an addition of 55 persons to its density. At the other end of the scale, Mansa Konko added only 6 persons to its density of 34 persons per km2 in 1983 and thus continued to have the lowest density of 40 persons per km2 in 1993. Mansa Konko was followed by Kuntaur with 46, Janjangbureh 62, Kerewan 69, and Basse 75.

Table 5: Area, Population & Density by Local Government Area (LGA) in 2003
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1993
Population in 2003
Decadal % Increase
% of Total 2003 Population
Population Density (Persons/km2)
Banjul
12
42 326
35 061
-17.2%
2.6%
2922
Kanifing
76
228 214
322 735
41.4%
23.7%
4247
Brikama
1 764
234 917
389 594
65.8%
28.6%
221
Mansa Konko
1 618
65 146
72 167
10.5%
5.3%
45
Kerewan
2 255
156 462
172 835
10.8%
12.7%
77
Kuntaur
1 467
67 774
78 491
15.8%
5.8%
54
Janjanbureh
1 428
88 247
107 212
21.5%
7.9%
75
Basse
2 070
155 059
182 586
17.8%
13.4%
88
The Gambia
10 690
1 038 145
1 360 680
31%
100%
127
Source: Jaiteh & Saho 2006



According to the 2003 census, the Gambia's population increased from 1, 038, 145 in 1993 to 1, 360, 680 people as shown in table 5. It indicated an addition of 322, 535 persons during the inter census period, which was slightly less than the 350, 328 people added in the previous decade. Thus, the population grew by 31% making it the lowest decadal growth rate percentagewise for the period under review.

From among the LGAs, as usual, it was only Brikama and Kanifing which registered growth rates higher than the national average of 31%. For the first time, Brikama took over from Kanifing as the LGA with the highest growth rate by recording 65.8% increment slightly less than the 71% recorded in the previous decade. Kanifing recorded a sharp decline in its growth rate from125% in the previous decade to only 41.4%. As it can be seen in figure 9, Kanifing’s  share of the total population marginally increased from 22.0% in 1993 to 23.7% in 2003, whilst that of Brikama increased from 22.6%  in 1993 to 28.6% in 2003.

Figure 8: LGAs by Population Size, 1993 & 2003
As usual, the remaining LGAs registered growth rates less than the national average of 31%. Among them Banjul continued to be at the bottom with a growth rate of negative 17.2%. Banjul was followed by Kerewan with a growth rate of 10.5%. Mansa Konko followed with a growth rate of 10.8%; Kuntaur 15.8%; Basse 17.8% and Janjangbureh 21.5% in that order. Hence, Brikama maintained its position as the most populous LGA and was followed by Kanifing in second place with an increasing margin. Basse followed in third place by relegating Kerewan to fourth. The remaining LGAs followed with Janjanbureh in fifth place; Kuntaur, sixth; Mansa Konko, seventh; and Banjul, eight.

Figure 9: LGAs Population as Percentage of 1993 & 2003 Population

The density of Gambia’s population also increased by 30 persons from 97 persons per km2 in 1993 to 127 persons per km2 in 2003 which was slightly less than the 33 persons added during the previous decade. At the LGA level, Kanifing surpassed Banjul as the LGA with the highest population density for the first time, it added 1,244 people to its density of 3,003 people per km2 in 1993; thus, recording a density of 4,247 people per km2 in 2003. Banjul followed with a density of 2,922 down from 3,527 in 1993 recording a reduction of 605 people per km2 in its density. Brikama followed with a density of 221 persons per km2 recording an addition of 84 persons per km2 to its density during the decade.

Routinely, the rest of the LGAs recorded increments less than 30 persons per km2. Among them Mansa Konko (45) was at the end of the scale, it added only 5 persons to its density of 40 persons per km2 during the decade. Kuntaur (54) followed Mansa Konko as usual, and then Janjangbureh came after Kuntaur (75), which was followed by Kerewan (77) and Basse (88).

As shown in map 2, the Gambia’s population distributional pattern has changed strikingly from 1963 to 2003. In 2003 the Gambia’s population has not only more than quadrupled to 1, 360, 681 in four decades, but has developed such an uneven distribution that the two Local Government Areas of Brikama with 389, 594 people, and Kanifing with 322, 735 people accounted for 52.4% of the 2003 total population, although they jointly occupied only 17.2% of the total land area. This change becomes more remarkable when 1963 data is referenced as they accounted for only 21.5% of the country’s population or 67, 601 people. This reveals that the Gambia’s population is not only characterized by rapid growth, but is increasingly skewed in its distribution.  Factors responsible for these changes important as they are fall beyond the scope of this paper which restricts itself to analyzing the changes in the pattern of distribution.

Although all the remaining LGAs registered a drop in their share of the total population from 1963 to 2003 as indicated by the histograms in map 2, it was more outstanding for Banjul and Mansa Konko, which interestingly are the Adjacent LGAs to Kanifing and Brikama respectively. Banjul’s share of the total population plummeted from 8.8% in 1963 to 2.6% in 2003, whilst that of Mansa Konko slumped from 10.8% in 1963 to 5.3% in 2003. Kuntaur, which had increased its share of the total population from 9.2% in 1963 to 9.7% in 1973 as shown in map 2, also recorded a significant drop in its proportion of the Gambia’s total population from 9.2% in 1963 to 5.8% in 2003. Similarly, Kerewan’s proportion of the total population dropped significantly from 20% in 1963 to 12.7% in 2003. Basse and Janjanbureh LGAs also recorded a continuous drop in their share of the Gambia’s total population from 18.4 and 11.3 percentage points in 1963 to 13.4 and 7.9 percentage points in 2003 respectively.

A comparison of the size of the Local Government Areas as percentage of the Gambia’s total land area with their population as proportion of the country’s 2003 total population would revealed the skewed nature of the distributional pattern of the Gambia’s population. For example, Kerewan being the largest LGA with 21.1% of the country’s total land area accounted for mere 12.7% of the country’s total population. Basse, which followed with 19.4% of the total land area accounted for just 13.4% of the total population. Brikama, the third largest LGA, with 16.5% of the total land area accounted for 28.6% of the 2003 total population and was the most populous LGA. Mansa Konko with 15.1% of the total land area was the fourth largest LGA; yet, it accounted for only 5.3% of the total population. Similarly, Kuntaur, the fifth largest LGA with 13.7% of land area accounted for mere 5.8% of the total population. Janjanbureh with 13.4% of the total land area was the sixth largest LGA and accounted for 7.9% of the total population. Kanifing, the seventh largest LGA, with just 0.7% of the total land area accounted for as much as 23.7% of the total population. Banjul, the smallest LGA, with only 0.1% of the total land area accounted for 2.6% of the country’s total population in 2003.
















Map2: Distribution of the Gambia's Population by Local Government Area

Analyzing the Changing Pattern of the Gambia’s Population Distribution Using Lorenz Curve
The Lorenz curve is a graphic depiction of distribution initially devised to indicate concentrations of income or wealth, but is now widely used in population geography to measure population concentrations when information about an area is available for equivalent areal units like LGAs. It involves plotting cumulative percentages of population of Local Government Areas against cumulative percentages of the areas of the LGAs. Units of areas are ranked according to the density of population in ascending order and then populations and areas of these units are totalled to give cumulative percentages of area and population as seen in table 6. The cumulative percentages of population are then plotted against the cumulative percentages of area and the points are joined together to form a ‘curve’ as seen in figure 10. If the curve follows a diagonal, it would indicate an even distribution of population; that means each Local Government Area contains a proportion of the Gambia’s total population equalled to its proportion of the country’s total land area. Usually, there is a considerable departure from this and the greater the curvature the greater the unevenness of the population distribution. The variation between the Lorenz curve and the diagonal is called the inequality gap and is equivalent to the index of concentration referred to as concentration index (CI).

The Concentration Index (CI) is the deviation of the curve from the diagonal line and it is the proportion of inequality in the distribution of population in relation to the area. A concentration index (CI) of zero is the diagonal on the Lorenz curve.  On the contrary, a concentration index (CI) of hundred indicates perfect concentration, which means that the entire population is confined in a single geographical unit. For instance, if the whole population of the Gambia is found in only one of the eight Local Government Areas, then CI would be equal to 100. Thus, the concentration index shows the percentage of population that should be redistributed to produce a perfect balance between the area and population. As shown in table 6, 13.1% of the Gambia’s population should have been redistributed to attain a perfect balance between the country’s population and area; whereas in 2003, this number had almost tripled to 37.6%. The Lorenz curve at figure 10 reveals this fact.

.
The concentration index (CI) is algebraically expressed as CI=1/2∑ |x-y| and it is equal to the maximum of |X-Y|. In table 6, 1963 population is represented by ya; and 2003 population by yb. Hence, for the year 1963, CI = 1/2∑ |x-ya| = ½(26.2) = 13.1. This is equal to the maximum of |X-Ya| with the corresponding values of 82.7 for X, and 69.7 for Ya, see table 6. For the year 2003, CI = 1/2∑ |x-yb| = ½(75.2) = 37.6, which is equal to the maximum of |X-Yb| with the corresponding values of 82.7 for X, and 45.1 for Yb as shown in table 6.


Table 6: Cumulative percentage of total land area and cumulative percentages of the total population for 2003 and 1963

Local Government  Area (LGA)
% Land Area
(x)
% of
1963 Population
(ya)
|x-ya|
Cumulative % Land Area
(X)
Cumulative % of 1963 Population
 (Ya)
|X -Ya|
% of 2003 Population
(yb)
|x-yb|
Cumulative % of 2003 Population
 (Yb)
|X-Yb|
The Gambia
100%
100%




100%



Mansa Konko
15.1%
10.8%
4.3
15.1
10.8
4.3
5.3%
9.8
5.3
9.8
Kuntaur
13.7%
9.2%
4.5
28.8
20.0
8.8
5.8%
7.9
11.1
17.7
Janjan
bureh
13.4%
11.3%
2.3
42.2
31.3
10.9
7.9%
5.5
19.0
23.7
Kerewan
21.1%
20.0%
1.1
63.3
51.3
12
12.7%
8.4
31.7
31.6
Basse
19.4%
18.4%
1.0
82.7
69.7
13
13.4%
6.0
45.1
37.6
Brikama
16.5%
17.6%
1.1
99.2
87.3
11.9
28.6%
12.1
73.7
25.5
Kanifing
0.7%
3.9%
3.2
99.9
91.2
8.7
23.7%
23.0
97.4
2.5
Banjul
0.1%
8.8%
8.7
100
100
0
2.6%
2.5
100
0

                                         ∑|x-ya| = 26.2                                                  ∑|x-yb| = 75.2
                                         CI=1/2∑|x-ya|                                              CI = 1/2∑|x-yb|
                                             = 13.1                                                            = 37.6








 CHANGING PATTERN OF GAMBIA’S POPULATION DISTRIBUTION 1963 TO 2003



ABSTRACT
The stresses of climate change and explosive state of demographic transition in developing countries like the Gambia have led to the transformation of their economic activities which initiated redistributive tendencies in their spatial patterns of employment opportunities. As a result, the spatial distributional pattern of population in these countries is also undergoing changes. Analysis of these changes is useful for administrative and socio economic planning in addressing issues like determining the electoral constituencies, the provision of education, health and other social facilities,  waste disposal and management, and more importantly for devising coping strategies for the adverse effects of climate change on fragile ecosystems and vulnerable groups. It is in this context that this paper looks at the changes that have taken place in the distribution of Gambia’s population from 1963 to 2003 based on data of the four censuses conducted during the period. Although the first country wide census in The Gambia took place as early as 1881, it was from 1963 that censuses of good quality have been conducted on defacto basis. Therefore, 1963 census data serve as the reference point for analysis of the Gambia’s population characteristics.

KEY WORDS: The Gambia, spatial, distributional pattern, change, analysis, census, data


INTRODUCTION
 One of the most important uses of the population census data is the information it provides about the population settlement pattern in a geographic area. It is pertinent, therefore,  to examine the changes in the pattern of spatial distribution of the Gambia’s population as revealed by the data of the four censuses that took place from 1963 to 2003 using the administrative region of a local government area (LGA) as the unit of analysis.

The concept of distribution of a population refers to the spatial pattern in which the population finds its location. Thus, the concern of spatial distribution is the pattern of spread which may be linear, dispersed, nucleated, or agglomerated among others. There are several methods of describing the spatial distribution of a population; among them the percentage distribution is the simplest which indicates the percentage of a population in a given class of geographical area. The other simple method is the rank order in which the geographical areas of a given class are listed in a rank for a census year to enable comparison between different census years in order to reveal the trend of population growth overtime. Besides, the median point, the mean point (the centre of population), the point of minimum aggregate travel, and the point of maximum population potential are used by population geographers to measure population distribution. However, in this analysis the simple methods of percentage distribution and rank order are used to examine the change in the Gambia’s population distribution from 1963 to 2003. Besides, Lorenz curve is used to compare the country’s population distribution pattern for 1963 and 2003.

Physical Features and Administrative Divisions
Situated between latitude 13N and 14N, and between longitude 14⁰W and 17⁰W on the bulge of the western coast of Africa along the Atlantic Ocean, with a total area of 11, 420 km2 and occupying a land area of 10, 690km2 (Jaiteh & Saho, 2006), the Gambia is the smallest country on mainland Africa. The country is surrounded by Senegal, its only neighbor, on all sides except the west which opens into the Atlantic Ocean.

The climate of the country is conditioned by its tropical latitude and the seasonal migration of the Inter Tropical Convergence Zone (ITCZ) – the line of low pressure at which the hot dry continental wind from the northeast meets the moist oceanic southwest wind to produce precipitation. Hence, the climate is characterized by a distinct dry season between November and May when the position of the ITCZ shifts towards the coast and the northeast trade winds, locally referred to as Harmattan, became dominant; and a wet season from June to October when the low pressure centre migrates to the interior thereby bringing the area under the influence of the southwest monsoons from the Atlantic. The influence of the Cool Canary Currents in this part of the Atlantic modified the coastal climate to a sub – tropical type which makes the climate of the area more conducive than the interior of the country which has a typical tropical climate of the Sudanic type.

Map 1: Elevation Map of the Gambia Adapted From Jaiteh & Sarr 2011

The River Gambia, after which the country is named, dominates the topography (see map 1) as it flows through the entire length of the country in east – west direction and its floodplains which are flanked by low laterite hills form the width of the country which is about 48km along the coast and 24km in the interior. Hence, the country is generally flat with more than 48% of the total land area below 20metres in elevation (Jaiteh & Saho, 2006). The river is politically significant too as its tributaries, locally known as bolongs, form the natural boundaries of most of the countries administrative regions.

The Gambia is divided into eight local administrative divisions which are designated as Local Government Areas (LGAs) and they form the basic unit of analysis for this paper because the country’s census data are aggregated according to this geographic class of LGA. The eight Local Government Areas comprise the city of Banjul (the seat of Government), the Kanifing Municipality, and the six local government areas of Brikama, Mansa Konko, Kerewan, Kuntaur, Janjangbureh and Basse. Each of these local government areas corresponds with an administrative region except for Janjangbureh and Kuntaur which jointly formed the Central River Region. The LGAs of Brikama, Mansa Konko, Kerewan, and Basse correspond with the West Coast Region, Lower River Region, North Bank Region and Upper River Region respectively.

Changes in Population Distribution by Census Year
Since 1963 census data is the bench mark for the study of this paper, it is important to analyse the pattern of distribution of the Gambia’s population in 1963 with respect to the land area.

Table 1: Area, Population & Density by Local Government Area (LGA) in 1963
Local Government Area (LGA)
Land Area (sq. km)
% of Total Land Area
Population in 1963
% of Total Population
Population Density Persons/km2
Banjul
12
0.1%
27 809
8.8%
2317
Kanifing
76
0.7%
12 208
3.9%
161
Brikama
1 764
16.5%
55 393
17.6%
31
Mansa Konko
1 618
15.1%
34 227
10.8%
21
Kerewan
2 255
21.1%
63 045
20.0%
28
Kuntaur
1 467
13.7%
29 003
9.2%
20
Janjanbureh
1 428
13.4%
35 752
11.3%
25
Basse
2 070
19.4%
58 049
18.4%
28
The Gambia
10 690
100%
315 486
100%
30
Sources: GoTG 1996, and Jaiteh & Saho 2006

The Gambia, as revealed by Table 1, had a total population of 315, 486 people in 1963. From among the various Local Government Areas, Kerewan was the most populated accounting for 20.0% of the Gambia’s total population in 1963; and Kanifing was the least populated, with only 3.9% of the country’s total population as shown in both Table 1 and Figure 1.

Figure 1: LGAs by Area and Population Size - 1963
Comparing the size of each LGA as a percentage of the total land area of The Gambia with its total population as a percentage of The Gambia’s 1963 population, as shown in figure 1, revealed a fairly even distribution. For instance, Kerewan Local Government Area accounted for 21.1% of the total land area and 20.0% of the total population. Similarly Basse LGA with 19.4% of the total land area accounted for 18.4% of the total population; and Brikama LGA with 16.5% of the total land area accounted for 17.6% of the 1963 total population. The pattern is not markedly different for Janjanbureh LGA with 13.4% of the total land area accounting for 11.3% of the total population. On the other hand, the LGAs of Mansa Konko and Kuntaur had significant differences between their sizes of land area (15.1% and 13.7%) and proportion of total population (10.8% and 9.2% respectively). The same is true for the LGAs of Banjul and Kanifing which accounted for larger proportion of population (8.8% and 3.9%) than land area (0.1% and 0.7%). It is intriguing to observe that the LGAs of Banjul, Kanifing and Brikama accounted for larger percentage of population than area whereas the remaining LGAs had larger percentage of area than population.

As shown in both Table 1 and Figure 1, the most populous LGA in 1963 was Kerewan, Followed by Basse, then Brikama, Janjanbureh, Mansa Konko, Kuntaur, Banjul and Kanifing. This matched fairly well with the ranking of LGAs according to size which has Kerewan as the largest, followed by Basse, then Brikama, Mansa Konko, Kuntaur, Janjanbureh, Kanifing and Banjul.

Since the Local Government Areas have very large differences in their areal extent, the density which deals with the ratio between the size of population and the area portrays a better picture of the population – resource relationship. The density of population is usually computed as population per square kilometer (km2) of land area. Different types of densities like arithmetic, physiological or nutritional, agricultural, and economic, are devised for utilization in different situations with the aim to arrive at a better indicator for the population resource relationship. In this paper the analysis of density is confined to the simple arithmetic density which refers to the ratio of population of a given geographical unit to the area occupied by that unit.

 As is evident from Table 1, in 1963 the Gambia had an average density of 30 persons per km2, the sharp differences between LGAs like Banjul (2,317 persons/km2) and Kuntaur (20 persons/km2) notwithstanding. From among the various LGAs, Banjul (2,317 persons/km2), Kanifing (161 persons/km2), and Brikama (31 persons/km2) had densities more than the national average. The remaining LGAs like Kerewan (28 persons/km2), Basse (28 persons/km2), Janjanbureh (25 persons/km2), Mansa Konko (21 persons/km2), and Kuntaur (20 persons/km2) had densities below the national average of 30 persons/km2. It is interesting to note that the densities for the large LGAs of Kerewan, Basse and Brikama were very close to the national average.


Table 2: Area, Population & Density by Local Government Area (LGA) in 1973
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1963
Population in 1973
Decadal % Increase
% of 1973 Total Population
Population Density (Persons/km2)
Banjul
12
27 809
39 179
41%
7.9%
3265
Kanifing
76
12 208
39 404
223%
8.0%
518
Brikama
1 764
55 393
91 013
64%
18.4%
52
Mansa Konko
1 618
34 227
42 447
24%
8.6%
26
Kerewan
2 255
63 045
93 388
48%
18.9%
41
Kuntaur
1 467
29 003
47 669
64%
9.7%
32
Janjanbureh
1 428
35 752
54 232
52%
11.0%
38
Basse
2 070
58 049
86 167
48%
17.5%
42
The Gambia
10 690
315 486
493 499
56%
100%
46
Sources: GoTG 1996, and Jaiteh & Saho 2006

According to table 2, the 1973 census revealed a 56% increase in the Gambia’s total population from 315, 486 people in 1963 to 493, 499 in 1973. It implied an addition of 178, 013 people within a decade. From among the various LGAs, as shown in figures 2 & 3, Kanifing recorded the highest increase in its share of population which had more than tripled from 12, 208 to 39, 404 people. It registered a whopping 223% increment in its population during the 1963 – 1973 inter census period. Consequently, its share of the total population more than doubled from 3.9% in 1963 to 8.0% in 1973. Next in line were Brikama and Kuntaur LGAs. The population of Brikama LGA rose from 55, 393 people to 91, 013 registering 64% increment in the inter census period. Similarly, Kuntaur Local Government Area’s population had increased by 64% from 29, 003 to 47, 669 people.

Figure 2: LGAs by Population Size, 1963 & 1973


In contrast, the population of Mansa Konko increased marginally from 34, 227 in 1963 to 42, 447 in 1973; and so, it registered only 24% increment during the inter census period. Hence, the LGA recorded a decline in its share of total population from 10.8% to 8.6%. Mansa Konko was followed by Banjul which recorded 41% increment from 27, 809 to 39, 179 people thereby becoming the least populated LGA in 1973, replacing Kanifing. The other LGAs with growth rates below the national average of 56% were Kerewan, the population of which grew from 63, 045 to 93, 388 people and it recorded 48% increment, Basse also recorded 48% increment as its population rose from 58, 049 to 86, 167 people. Janjanbureh’s population grew from 35, 752 to 54 232 persons and it registered 52% increment.





Figure 3: LGAs Population as Percentage of 1963 & 1973 Population

 The 1973 census revealed a decrease in the share of population of all the LGAs except for Kanifing, Brikama and Kuntaur. Thus, the rank order of the LGAs according to population got slightly modified with Brikama replacing Basse as the second most populated LGA after Kerewan. Similarly Kuntaur replaced Mansa Konko as the fifth most populated LGA and Banjul was relegated to the bottom replacing Kanifing which took over its position as the seventh most populated LGA.

The Gambia in the decade 1963 – 73 had registered an increase of 16 persons in the average density of her population from 30 /km2 to 46 /km2. Among the various LGAs, Banjul had maintained its distinction of having the highest density of population (3, 265). It was followed by Kanifing which had more than tripled its density from 161 to 518. Brikama with a density of 52 persons/km2 followed Kanifing. At the other end of the scale was Mansa Konko (26) which replaced Kuntaur as the LGA with the lowest density in the country. It was followed by Kuntaur (32), Janjanbureh (38), Kerewan (41) and Basse (42).

Table 3: Area, Population & Density by Local Government Area (LGA) in 1983
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1973
Population in 1983
Decadal % Increase
% of 1983 Total Population
Population Density (Persons/km2)
Banjul
12
39 179
44 188
13%
6.4%
3682
Kanifing
76
39 404
101 504
158%
14.8%
1336
Brikama
1 764
91 013
137 245
51%
20.0%
78
Mansa Konko
1 618
42 447
55 263
30%
8.0%
34
Kerewan
2 255
93 388
112 225
20%
16.3%
50
Kuntaur
1 467
47 669
57 594
21%
8.4%
39
Janjanbureh
1 428
54 232
68 410
26%
9.9%
48
Basse
2 070
86 167
111 388
29%
16.2%
54
The Gambia
10 690
493 499
687 817
39%
100%
64
Sources: GoTG 1996, and Jaiteh & Saho 2006

According to the 1983 census, as shown in table 3, the Gambia’s population grew from 493, 499 people in 1973 to 687, 817 in 1983 revealing a 39% increase which was lower than the 1963 – 73 inter decadal increment of 56%. However, in absolute terms, it indicated an addition of 194, 318 people within the decade which was more than the178, 013 people added in the previous decade.




Figure 4: LGAs by Population Size, 1973 & 1983
From among the LGAs, as shown in figure 4, only Kanifing and Brikama recorded growth rates higher than the national average of 39%. Kanifing had maintained its distinction of having the highest growth rate of 158% by more than doubling its population from 39, 404 in 1973 to 101, 504 people in 1983. Hence, it increased its share of the total population from 8.0% in 1973 to 14.6% in 1983 as shown in figure 5; which made it the fourth largest populated LGA for that census year. Brikama also maintained its position as the second fastest growing LGA with a growth rate of 51% from 91, 013 in 1973 to 137, 245 people in 1983. Consequently, it became the most populous LGA in 1983 accounting for 20% of the country’s total population.

Figure 5: LGAs Population as Percentage of 1973 & 1983 Population

From among the LGAs with growth rates less than the national average of 39% during the decade, Banjul registered the lowest growth rate of 13% in 1983 followed by Kerewan (20%), Kuntaur (21%), Janjanbureh (26%), Basse (29%) and Mansa Konko (30%) in that order.

The trend of change observed in 1983 was similar to that of 1973, except that Kuntaur had joined the LGAs with growth rates lower than the national average of 39%. That made Kanifing and Brikama to be the only LGAs with growth rates more than the national average. As a result, the rank order of the LGAs according to population size got modified with Brikama replacing Kerewan as the most populous which followed in second place, then Basse (which closely followed Kerewan), Kanifing (which moved up from seventh position), Janjanbureh, Kuntaur,  Mansa Konko and Banjul.

The 1983 census revealed an average density of 64 persons per km2 for the country, implying an addition of 17 people to the country’s density of 47 in 1973, which was almost the same as the number added in the previous decade. From among the LGAs Banjul maintained the highest with a density of 3, 682 persons per km2 followed by Kanifing which had more than doubled its density from 518 persons per km2 in 1973 to 1, 336 persons per km2 in 1983. Brikama followed with a density of 78, for the LG As with densities more than the national average of 64. For the LGAs with densities less than the national average, Mansa Konko maintained the lowest position with 34 persons per km2, followed by Kuntaur (39), Janjanbureh (48), Kerewan (50) and Basse (54) in that order.

Table 4: Area, Population & Density by Local Government Area (LGA) in 1993
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1983
Population in 1993
Decadal % Increase
% of Total Population
Population Density (Persons/km2)
Banjul
12
44 188
42 326
-4%
4.1%
3527
Kanifing
76
101 504
228 214
125%
22.0%
3003
Brikama
1 764
137 245
234 917
71%
22.6%
133
Mansa Konko
1 618
55 263
65 146
17.9%
6.3%
40
Kerewan
2 255
112 225
156 462
39.4%
15.1%
69
Kuntaur
1 467
57 594
67 774
17.7%
6.5%
46
Janjanbureh
1 428
68 410
88 247
29%
8.5%
62
Basse
2 070
111 388
155 059
39.2%
14.9%
75
The Gambia
10 690
687 817
1 038 145
51%
100%
97
Sources: GoTG 1996, and Jaiteh & Saho 2006

The 1993 census, as shown in Table 4, revealed that the Gambia had a population of 1, 038, 145 people and it registered 51% growth rate during the inter census period. It pointed out an addition of 350, 328 people to the country’s population within a decade; a number which was more than the Gambia’s 1963 total population of 315, 486 people and almost doubled the 178, 013 persons added in the decade before.

Figure 6: LGAs by Population Size, 1983 & 1993
                 

From among the LGAs Kanifing and Brikama continued to register growth rates higher than the national average.  As shown in table 4 & figure 6, Kanifing’s population jumped from 101, 504 in 1983 to 228, 214 people in 1993 registering 125% increment in its population during the decade. Accordingly, as shown in figure 7, its share of the total population soared from 14.8% in 1983 to 22.0% in 1993 making it the second most populous LGA in the country. Characteristically, Brikama followed as the second fastest growing LGA with a growth rate of 71%. Having increased its population from 137, 245 in 1983 to 234, 917  people in 1993 which represented 22.6% of the country’s total population for that year, Brikama continued to be the most populous LGA; although, closely followed by Kanifing as shown in figure 7.




Figure 7: LGAs Population as Percentage of 1983 & 1993 Population


The rest of the LGAs, as usual, registered growth rates less than the national average of 51% with Banjul (which for the first time recorded a negative growth rate of -4%) at the end of the scale. Banjul was followed by Kuntaur (17.7%), Mansa Konko (17.9%), Janjangbureh (29%), Basse (39.2%) and Kerewan (39.4%) in that order. Thus, the trend of change observed in 1993 was identical to that of 1983 as Kanifing continued to move swiftly up the rank by relegating both Kerewan and Basse to occupy second position after Brikama. Therefore, Brikama continued to be the most populous LGA in 1993, closely followed by Kanifing, then Kerewan, Basse, Janjanbureh, Kuntaur, Mansakonko and Banjul.

The 1993 census revealed an average density of 97 persons per km2 for Gambia as a whole, implying an addition of 33 persons to the country’s density of 64 in 1983.  Thus, the decade witnessed the highest increase in the country’s density which almost doubled the 17 people increment of the previous decade. From among the LGAs, Banjul continued to maintain having the highest density although its density declined slightly from 3,682 persons per km2 in 1983 to 3,527 persons per km2 in 1993. Banjul was closely followed by Kanifing which has more than doubled its density from 1,336 persons per km2 in 1983 to 3,003 persons per km2 in 1993. Brikama, as usual, followed Kanifing with a density of 133 persons per km2 in 1993; up from 78 persons per km2 in 1983 implying an addition of 55 persons to its density. At the other end of the scale, Mansa Konko added only 6 persons to its density of 34 persons per km2 in 1983 and thus continued to have the lowest density of 40 persons per km2 in 1993. Mansa Konko was followed by Kuntaur with 46, Janjangbureh 62, Kerewan 69, and Basse 75.

Table 5: Area, Population & Density by Local Government Area (LGA) in 2003
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1993
Population in 2003
Decadal % Increase
% of Total 2003 Population
Population Density (Persons/km2)
Banjul
12
42 326
35 061
-17.2%
2.6%
2922
Kanifing
76
228 214
322 735
41.4%
23.7%
4247
Brikama
1 764
234 917
389 594
65.8%
28.6%
221
Mansa Konko
1 618
65 146
72 167
10.5%
5.3%
45
Kerewan
2 255
156 462
172 835
10.8%
12.7%
77
Kuntaur
1 467
67 774
78 491
15.8%
5.8%
54
Janjanbureh
1 428
88 247
107 212
21.5%
7.9%
75
Basse
2 070
155 059
182 586
17.8%
13.4%
88
The Gambia
10 690
1 038 145
1 360 680
31%
100%
127
Source: Jaiteh & Saho 2006



According to the 2003 census, the Gambia's population increased from 1, 038, 145 in 1993 to 1, 360, 680 people as shown in table 5. It indicated an addition of 322, 535 persons during the inter census period, which was slightly less than the 350, 328 people added in the previous decade. Thus, the population grew by 31% making it the lowest decadal growth rate percentagewise for the period under review.

From among the LGAs, as usual, it was only Brikama and Kanifing which registered growth rates higher than the national average of 31%. For the first time, Brikama took over from Kanifing as the LGA with the highest growth rate by recording 65.8% increment slightly less than the 71% recorded in the previous decade. Kanifing recorded a sharp decline in its growth rate from125% in the previous decade to only 41.4%. As it can be seen in figure 9, Kanifing’s  share of the total population marginally increased from 22.0% in 1993 to 23.7% in 2003, whilst that of Brikama increased from 22.6%  in 1993 to 28.6% in 2003.

Figure 8: LGAs by Population Size, 1993 & 2003
As usual, the remaining LGAs registered growth rates less than the national average of 31%. Among them Banjul continued to be at the bottom with a growth rate of negative 17.2%. Banjul was followed by Kerewan with a growth rate of 10.5%. Mansa Konko followed with a growth rate of 10.8%; Kuntaur 15.8%; Basse 17.8% and Janjangbureh 21.5% in that order. Hence, Brikama maintained its position as the most populous LGA and was followed by Kanifing in second place with an increasing margin. Basse followed in third place by relegating Kerewan to fourth. The remaining LGAs followed with Janjanbureh in fifth place; Kuntaur, sixth; Mansa Konko, seventh; and Banjul, eight.

Figure 9: LGAs Population as Percentage of 1993 & 2003 Population

The density of Gambia’s population also increased by 30 persons from 97 persons per km2 in 1993 to 127 persons per km2 in 2003 which was slightly less than the 33 persons added during the previous decade. At the LGA level, Kanifing surpassed Banjul as the LGA with the highest population density for the first time, it added 1,244 people to its density of 3,003 people per km2 in 1993; thus, recording a density of 4,247 people per km2 in 2003. Banjul followed with a density of 2,922 down from 3,527 in 1993 recording a reduction of 605 people per km2 in its density. Brikama followed with a density of 221 persons per km2 recording an addition of 84 persons per km2 to its density during the decade.

Routinely, the rest of the LGAs recorded increments less than 30 persons per km2. Among them Mansa Konko (45) was at the end of the scale, it added only 5 persons to its density of 40 persons per km2 during the decade. Kuntaur (54) followed Mansa Konko as usual, and then Janjangbureh came after Kuntaur (75), which was followed by Kerewan (77) and Basse (88).

As shown in map 2, the Gambia’s population distributional pattern has changed strikingly from 1963 to 2003. In 2003 the Gambia’s population has not only more than quadrupled to 1, 360, 681 in four decades, but has developed such an uneven distribution that the two Local Government Areas of Brikama with 389, 594 people, and Kanifing with 322, 735 people accounted for 52.4% of the 2003 total population, although they jointly occupied only 17.2% of the total land area. This change becomes more remarkable when 1963 data is referenced as they accounted for only 21.5% of the country’s population or 67, 601 people. This reveals that the Gambia’s population is not only characterized by rapid growth, but is increasingly skewed in its distribution.  Factors responsible for these changes important as they are fall beyond the scope of this paper which restricts itself to analyzing the changes in the pattern of distribution.

Although all the remaining LGAs registered a drop in their share of the total population from 1963 to 2003 as indicated by the histograms in map 2, it was more outstanding for Banjul and Mansa Konko, which interestingly are the Adjacent LGAs to Kanifing and Brikama respectively. Banjul’s share of the total population plummeted from 8.8% in 1963 to 2.6% in 2003, whilst that of Mansa Konko slumped from 10.8% in 1963 to 5.3% in 2003. Kuntaur, which had increased its share of the total population from 9.2% in 1963 to 9.7% in 1973 as shown in map 2, also recorded a significant drop in its proportion of the Gambia’s total population from 9.2% in 1963 to 5.8% in 2003. Similarly, Kerewan’s proportion of the total population dropped significantly from 20% in 1963 to 12.7% in 2003. Basse and Janjanbureh LGAs also recorded a continuous drop in their share of the Gambia’s total population from 18.4 and 11.3 percentage points in 1963 to 13.4 and 7.9 percentage points in 2003 respectively.

A comparison of the size of the Local Government Areas as percentage of the Gambia’s total land area with their population as proportion of the country’s 2003 total population would revealed the skewed nature of the distributional pattern of the Gambia’s population. For example, Kerewan being the largest LGA with 21.1% of the country’s total land area accounted for mere 12.7% of the country’s total population. Basse, which followed with 19.4% of the total land area accounted for just 13.4% of the total population. Brikama, the third largest LGA, with 16.5% of the total land area accounted for 28.6% of the 2003 total population and was the most populous LGA. Mansa Konko with 15.1% of the total land area was the fourth largest LGA; yet, it accounted for only 5.3% of the total population. Similarly, Kuntaur, the fifth largest LGA with 13.7% of land area accounted for mere 5.8% of the total population. Janjanbureh with 13.4% of the total land area was the sixth largest LGA and accounted for 7.9% of the total population. Kanifing, the seventh largest LGA, with just 0.7% of the total land area accounted for as much as 23.7% of the total population. Banjul, the smallest LGA, with only 0.1% of the total land area accounted for 2.6% of the country’s total population in 2003.
















Map2: Distribution of the Gambia's Population by Local Government Area

Analyzing the Changing Pattern of the Gambia’s Population Distribution Using Lorenz Curve
The Lorenz curve is a graphic depiction of distribution initially devised to indicate concentrations of income or wealth, but is now widely used in population geography to measure population concentrations when information about an area is available for equivalent areal units like LGAs. It involves plotting cumulative percentages of population of Local Government Areas against cumulative percentages of the areas of the LGAs. Units of areas are ranked according to the density of population in ascending order and then populations and areas of these units are totalled to give cumulative percentages of area and population as seen in table 6. The cumulative percentages of population are then plotted against the cumulative percentages of area and the points are joined together to form a ‘curve’ as seen in figure 10. If the curve follows a diagonal, it would indicate an even distribution of population; that means each Local Government Area contains a proportion of the Gambia’s total population equalled to its proportion of the country’s total land area. Usually, there is a considerable departure from this and the greater the curvature the greater the unevenness of the population distribution. The variation between the Lorenz curve and the diagonal is called the inequality gap and is equivalent to the index of concentration referred to as concentration index (CI).

The Concentration Index (CI) is the deviation of the curve from the diagonal line and it is the proportion of inequality in the distribution of population in relation to the area. A concentration index (CI) of zero is the diagonal on the Lorenz curve.  On the contrary, a concentration index (CI) of hundred indicates perfect concentration, which means that the entire population is confined in a single geographical unit. For instance, if the whole population of the Gambia is found in only one of the eight Local Government Areas, then CI would be equal to 100. Thus, the concentration index shows the percentage of population that should be redistributed to produce a perfect balance between the area and population. As shown in table 6, 13.1% of the Gambia’s population should have been redistributed to attain a perfect balance between the country’s population and area; whereas in 2003, this number had almost tripled to 37.6%. The Lorenz curve at figure 10 reveals this fact.

.
The concentration index (CI) is algebraically expressed as CI=1/2∑ |x-y| and it is equal to the maximum of |X-Y|. In table 6, 1963 population is represented by ya; and 2003 population by yb. Hence, for the year 1963, CI = 1/2∑ |x-ya| = ½(26.2) = 13.1. This is equal to the maximum of |X-Ya| with the corresponding values of 82.7 for X, and 69.7 for Ya, see table 6. For the year 2003, CI = 1/2∑ |x-yb| = ½(75.2) = 37.6, which is equal to the maximum of |X-Yb| with the corresponding values of 82.7 for X, and 45.1 for Yb as shown in table 6.


Table 6: Cumulative percentage of total land area and cumulative percentages of the total population for 2003 and 1963

Local Government  Area (LGA)
% Land Area
(x)
% of
1963 Population
(ya)
|x-ya|
Cumulative % Land Area
(X)
Cumulative % of 1963 Population
 (Ya)
|X -Ya|
% of 2003 Population
(yb)
|x-yb|
Cumulative % of 2003 Population
 (Yb)
|X-Yb|
The Gambia
100%
100%




100%



Mansa Konko
15.1%
10.8%
4.3
15.1
10.8
4.3
5.3%
9.8
5.3
9.8
Kuntaur
13.7%
9.2%
4.5
28.8
20.0
8.8
5.8%
7.9
11.1
17.7
Janjan
bureh
13.4%
11.3%
2.3
42.2
31.3
10.9
7.9%
5.5
19.0
23.7
Kerewan
21.1%
20.0%
1.1
63.3
51.3
12
12.7%
8.4
31.7
31.6
Basse
19.4%
18.4%
1.0
82.7
69.7
13
13.4%
6.0
45.1
37.6
Brikama
16.5%
17.6%
1.1
99.2
87.3
11.9
28.6%
12.1
73.7
25.5
Kanifing
0.7%
3.9%
3.2
99.9
91.2
8.7
23.7%
23.0
97.4
2.5
Banjul
0.1%
8.8%
8.7
100
100
0
2.6%
2.5
100
0

                                         ∑|x-ya| = 26.2                                                  ∑|x-yb| = 75.2
                                         CI=1/2∑|x-ya|                                              CI = 1/2∑|x-yb|
                                             = 13.1                                                            = 37.6














 CHANGING PATTERN OF GAMBIA’S POPULATION DISTRIBUTION 1963 TO 2003



ABSTRACT
The stresses of climate change and explosive state of demographic transition in developing countries like the Gambia have led to the transformation of their economic activities which initiated redistributive tendencies in their spatial patterns of employment opportunities. As a result, the spatial distributional pattern of population in these countries is also undergoing changes. Analysis of these changes is useful for administrative and socio economic planning in addressing issues like determining the electoral constituencies, the provision of education, health and other social facilities,  waste disposal and management, and more importantly for devising coping strategies for the adverse effects of climate change on fragile ecosystems and vulnerable groups. It is in this context that this paper looks at the changes that have taken place in the distribution of Gambia’s population from 1963 to 2003 based on data of the four censuses conducted during the period. Although the first country wide census in The Gambia took place as early as 1881, it was from 1963 that censuses of good quality have been conducted on defacto basis. Therefore, 1963 census data serve as the reference point for analysis of the Gambia’s population characteristics.

KEY WORDS: The Gambia, spatial, distributional pattern, change, analysis, census, data


INTRODUCTION
 One of the most important uses of the population census data is the information it provides about the population settlement pattern in a geographic area. It is pertinent, therefore,  to examine the changes in the pattern of spatial distribution of the Gambia’s population as revealed by the data of the four censuses that took place from 1963 to 2003 using the administrative region of a local government area (LGA) as the unit of analysis.

The concept of distribution of a population refers to the spatial pattern in which the population finds its location. Thus, the concern of spatial distribution is the pattern of spread which may be linear, dispersed, nucleated, or agglomerated among others. There are several methods of describing the spatial distribution of a population; among them the percentage distribution is the simplest which indicates the percentage of a population in a given class of geographical area. The other simple method is the rank order in which the geographical areas of a given class are listed in a rank for a census year to enable comparison between different census years in order to reveal the trend of population growth overtime. Besides, the median point, the mean point (the centre of population), the point of minimum aggregate travel, and the point of maximum population potential are used by population geographers to measure population distribution. However, in this analysis the simple methods of percentage distribution and rank order are used to examine the change in the Gambia’s population distribution from 1963 to 2003. Besides, Lorenz curve is used to compare the country’s population distribution pattern for 1963 and 2003.

Physical Features and Administrative Divisions
Situated between latitude 13N and 14N, and between longitude 14⁰W and 17⁰W on the bulge of the western coast of Africa along the Atlantic Ocean, with a total area of 11, 420 km2 and occupying a land area of 10, 690km2 (Jaiteh & Saho, 2006), the Gambia is the smallest country on mainland Africa. The country is surrounded by Senegal, its only neighbor, on all sides except the west which opens into the Atlantic Ocean.

The climate of the country is conditioned by its tropical latitude and the seasonal migration of the Inter Tropical Convergence Zone (ITCZ) – the line of low pressure at which the hot dry continental wind from the northeast meets the moist oceanic southwest wind to produce precipitation. Hence, the climate is characterized by a distinct dry season between November and May when the position of the ITCZ shifts towards the coast and the northeast trade winds, locally referred to as Harmattan, became dominant; and a wet season from June to October when the low pressure centre migrates to the interior thereby bringing the area under the influence of the southwest monsoons from the Atlantic. The influence of the Cool Canary Currents in this part of the Atlantic modified the coastal climate to a sub – tropical type which makes the climate of the area more conducive than the interior of the country which has a typical tropical climate of the Sudanic type.

Map 1: Elevation Map of the Gambia Adapted From Jaiteh & Sarr 2011

The River Gambia, after which the country is named, dominates the topography (see map 1) as it flows through the entire length of the country in east – west direction and its floodplains which are flanked by low laterite hills form the width of the country which is about 48km along the coast and 24km in the interior. Hence, the country is generally flat with more than 48% of the total land area below 20metres in elevation (Jaiteh & Saho, 2006). The river is politically significant too as its tributaries, locally known as bolongs, form the natural boundaries of most of the countries administrative regions.

The Gambia is divided into eight local administrative divisions which are designated as Local Government Areas (LGAs) and they form the basic unit of analysis for this paper because the country’s census data are aggregated according to this geographic class of LGA. The eight Local Government Areas comprise the city of Banjul (the seat of Government), the Kanifing Municipality, and the six local government areas of Brikama, Mansa Konko, Kerewan, Kuntaur, Janjangbureh and Basse. Each of these local government areas corresponds with an administrative region except for Janjangbureh and Kuntaur which jointly formed the Central River Region. The LGAs of Brikama, Mansa Konko, Kerewan, and Basse correspond with the West Coast Region, Lower River Region, North Bank Region and Upper River Region respectively.

Changes in Population Distribution by Census Year
Since 1963 census data is the bench mark for the study of this paper, it is important to analyse the pattern of distribution of the Gambia’s population in 1963 with respect to the land area.

Table 1: Area, Population & Density by Local Government Area (LGA) in 1963
Local Government Area (LGA)
Land Area (sq. km)
% of Total Land Area
Population in 1963
% of Total Population
Population Density Persons/km2
Banjul
12
0.1%
27 809
8.8%
2317
Kanifing
76
0.7%
12 208
3.9%
161
Brikama
1 764
16.5%
55 393
17.6%
31
Mansa Konko
1 618
15.1%
34 227
10.8%
21
Kerewan
2 255
21.1%
63 045
20.0%
28
Kuntaur
1 467
13.7%
29 003
9.2%
20
Janjanbureh
1 428
13.4%
35 752
11.3%
25
Basse
2 070
19.4%
58 049
18.4%
28
The Gambia
10 690
100%
315 486
100%
30
Sources: GoTG 1996, and Jaiteh & Saho 2006

The Gambia, as revealed by Table 1, had a total population of 315, 486 people in 1963. From among the various Local Government Areas, Kerewan was the most populated accounting for 20.0% of the Gambia’s total population in 1963; and Kanifing was the least populated, with only 3.9% of the country’s total population as shown in both Table 1 and Figure 1.

Figure 1: LGAs by Area and Population Size - 1963
Comparing the size of each LGA as a percentage of the total land area of The Gambia with its total population as a percentage of The Gambia’s 1963 population, as shown in figure 1, revealed a fairly even distribution. For instance, Kerewan Local Government Area accounted for 21.1% of the total land area and 20.0% of the total population. Similarly Basse LGA with 19.4% of the total land area accounted for 18.4% of the total population; and Brikama LGA with 16.5% of the total land area accounted for 17.6% of the 1963 total population. The pattern is not markedly different for Janjanbureh LGA with 13.4% of the total land area accounting for 11.3% of the total population. On the other hand, the LGAs of Mansa Konko and Kuntaur had significant differences between their sizes of land area (15.1% and 13.7%) and proportion of total population (10.8% and 9.2% respectively). The same is true for the LGAs of Banjul and Kanifing which accounted for larger proportion of population (8.8% and 3.9%) than land area (0.1% and 0.7%). It is intriguing to observe that the LGAs of Banjul, Kanifing and Brikama accounted for larger percentage of population than area whereas the remaining LGAs had larger percentage of area than population.

As shown in both Table 1 and Figure 1, the most populous LGA in 1963 was Kerewan, Followed by Basse, then Brikama, Janjanbureh, Mansa Konko, Kuntaur, Banjul and Kanifing. This matched fairly well with the ranking of LGAs according to size which has Kerewan as the largest, followed by Basse, then Brikama, Mansa Konko, Kuntaur, Janjanbureh, Kanifing and Banjul.

Since the Local Government Areas have very large differences in their areal extent, the density which deals with the ratio between the size of population and the area portrays a better picture of the population – resource relationship. The density of population is usually computed as population per square kilometer (km2) of land area. Different types of densities like arithmetic, physiological or nutritional, agricultural, and economic, are devised for utilization in different situations with the aim to arrive at a better indicator for the population resource relationship. In this paper the analysis of density is confined to the simple arithmetic density which refers to the ratio of population of a given geographical unit to the area occupied by that unit.

 As is evident from Table 1, in 1963 the Gambia had an average density of 30 persons per km2, the sharp differences between LGAs like Banjul (2,317 persons/km2) and Kuntaur (20 persons/km2) notwithstanding. From among the various LGAs, Banjul (2,317 persons/km2), Kanifing (161 persons/km2), and Brikama (31 persons/km2) had densities more than the national average. The remaining LGAs like Kerewan (28 persons/km2), Basse (28 persons/km2), Janjanbureh (25 persons/km2), Mansa Konko (21 persons/km2), and Kuntaur (20 persons/km2) had densities below the national average of 30 persons/km2. It is interesting to note that the densities for the large LGAs of Kerewan, Basse and Brikama were very close to the national average.


Table 2: Area, Population & Density by Local Government Area (LGA) in 1973
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1963
Population in 1973
Decadal % Increase
% of 1973 Total Population
Population Density (Persons/km2)
Banjul
12
27 809
39 179
41%
7.9%
3265
Kanifing
76
12 208
39 404
223%
8.0%
518
Brikama
1 764
55 393
91 013
64%
18.4%
52
Mansa Konko
1 618
34 227
42 447
24%
8.6%
26
Kerewan
2 255
63 045
93 388
48%
18.9%
41
Kuntaur
1 467
29 003
47 669
64%
9.7%
32
Janjanbureh
1 428
35 752
54 232
52%
11.0%
38
Basse
2 070
58 049
86 167
48%
17.5%
42
The Gambia
10 690
315 486
493 499
56%
100%
46
Sources: GoTG 1996, and Jaiteh & Saho 2006

According to table 2, the 1973 census revealed a 56% increase in the Gambia’s total population from 315, 486 people in 1963 to 493, 499 in 1973. It implied an addition of 178, 013 people within a decade. From among the various LGAs, as shown in figures 2 & 3, Kanifing recorded the highest increase in its share of population which had more than tripled from 12, 208 to 39, 404 people. It registered a whopping 223% increment in its population during the 1963 – 1973 inter census period. Consequently, its share of the total population more than doubled from 3.9% in 1963 to 8.0% in 1973. Next in line were Brikama and Kuntaur LGAs. The population of Brikama LGA rose from 55, 393 people to 91, 013 registering 64% increment in the inter census period. Similarly, Kuntaur Local Government Area’s population had increased by 64% from 29, 003 to 47, 669 people.

Figure 2: LGAs by Population Size, 1963 & 1973


In contrast, the population of Mansa Konko increased marginally from 34, 227 in 1963 to 42, 447 in 1973; and so, it registered only 24% increment during the inter census period. Hence, the LGA recorded a decline in its share of total population from 10.8% to 8.6%. Mansa Konko was followed by Banjul which recorded 41% increment from 27, 809 to 39, 179 people thereby becoming the least populated LGA in 1973, replacing Kanifing. The other LGAs with growth rates below the national average of 56% were Kerewan, the population of which grew from 63, 045 to 93, 388 people and it recorded 48% increment, Basse also recorded 48% increment as its population rose from 58, 049 to 86, 167 people. Janjanbureh’s population grew from 35, 752 to 54 232 persons and it registered 52% increment.





Figure 3: LGAs Population as Percentage of 1963 & 1973 Population

 The 1973 census revealed a decrease in the share of population of all the LGAs except for Kanifing, Brikama and Kuntaur. Thus, the rank order of the LGAs according to population got slightly modified with Brikama replacing Basse as the second most populated LGA after Kerewan. Similarly Kuntaur replaced Mansa Konko as the fifth most populated LGA and Banjul was relegated to the bottom replacing Kanifing which took over its position as the seventh most populated LGA.

The Gambia in the decade 1963 – 73 had registered an increase of 16 persons in the average density of her population from 30 /km2 to 46 /km2. Among the various LGAs, Banjul had maintained its distinction of having the highest density of population (3, 265). It was followed by Kanifing which had more than tripled its density from 161 to 518. Brikama with a density of 52 persons/km2 followed Kanifing. At the other end of the scale was Mansa Konko (26) which replaced Kuntaur as the LGA with the lowest density in the country. It was followed by Kuntaur (32), Janjanbureh (38), Kerewan (41) and Basse (42).

Table 3: Area, Population & Density by Local Government Area (LGA) in 1983
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1973
Population in 1983
Decadal % Increase
% of 1983 Total Population
Population Density (Persons/km2)
Banjul
12
39 179
44 188
13%
6.4%
3682
Kanifing
76
39 404
101 504
158%
14.8%
1336
Brikama
1 764
91 013
137 245
51%
20.0%
78
Mansa Konko
1 618
42 447
55 263
30%
8.0%
34
Kerewan
2 255
93 388
112 225
20%
16.3%
50
Kuntaur
1 467
47 669
57 594
21%
8.4%
39
Janjanbureh
1 428
54 232
68 410
26%
9.9%
48
Basse
2 070
86 167
111 388
29%
16.2%
54
The Gambia
10 690
493 499
687 817
39%
100%
64
Sources: GoTG 1996, and Jaiteh & Saho 2006

According to the 1983 census, as shown in table 3, the Gambia’s population grew from 493, 499 people in 1973 to 687, 817 in 1983 revealing a 39% increase which was lower than the 1963 – 73 inter decadal increment of 56%. However, in absolute terms, it indicated an addition of 194, 318 people within the decade which was more than the178, 013 people added in the previous decade.




Figure 4: LGAs by Population Size, 1973 & 1983
From among the LGAs, as shown in figure 4, only Kanifing and Brikama recorded growth rates higher than the national average of 39%. Kanifing had maintained its distinction of having the highest growth rate of 158% by more than doubling its population from 39, 404 in 1973 to 101, 504 people in 1983. Hence, it increased its share of the total population from 8.0% in 1973 to 14.6% in 1983 as shown in figure 5; which made it the fourth largest populated LGA for that census year. Brikama also maintained its position as the second fastest growing LGA with a growth rate of 51% from 91, 013 in 1973 to 137, 245 people in 1983. Consequently, it became the most populous LGA in 1983 accounting for 20% of the country’s total population.

Figure 5: LGAs Population as Percentage of 1973 & 1983 Population

From among the LGAs with growth rates less than the national average of 39% during the decade, Banjul registered the lowest growth rate of 13% in 1983 followed by Kerewan (20%), Kuntaur (21%), Janjanbureh (26%), Basse (29%) and Mansa Konko (30%) in that order.

The trend of change observed in 1983 was similar to that of 1973, except that Kuntaur had joined the LGAs with growth rates lower than the national average of 39%. That made Kanifing and Brikama to be the only LGAs with growth rates more than the national average. As a result, the rank order of the LGAs according to population size got modified with Brikama replacing Kerewan as the most populous which followed in second place, then Basse (which closely followed Kerewan), Kanifing (which moved up from seventh position), Janjanbureh, Kuntaur,  Mansa Konko and Banjul.

The 1983 census revealed an average density of 64 persons per km2 for the country, implying an addition of 17 people to the country’s density of 47 in 1973, which was almost the same as the number added in the previous decade. From among the LGAs Banjul maintained the highest with a density of 3, 682 persons per km2 followed by Kanifing which had more than doubled its density from 518 persons per km2 in 1973 to 1, 336 persons per km2 in 1983. Brikama followed with a density of 78, for the LG As with densities more than the national average of 64. For the LGAs with densities less than the national average, Mansa Konko maintained the lowest position with 34 persons per km2, followed by Kuntaur (39), Janjanbureh (48), Kerewan (50) and Basse (54) in that order.

Table 4: Area, Population & Density by Local Government Area (LGA) in 1993
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1983
Population in 1993
Decadal % Increase
% of Total Population
Population Density (Persons/km2)
Banjul
12
44 188
42 326
-4%
4.1%
3527
Kanifing
76
101 504
228 214
125%
22.0%
3003
Brikama
1 764
137 245
234 917
71%
22.6%
133
Mansa Konko
1 618
55 263
65 146
17.9%
6.3%
40
Kerewan
2 255
112 225
156 462
39.4%
15.1%
69
Kuntaur
1 467
57 594
67 774
17.7%
6.5%
46
Janjanbureh
1 428
68 410
88 247
29%
8.5%
62
Basse
2 070
111 388
155 059
39.2%
14.9%
75
The Gambia
10 690
687 817
1 038 145
51%
100%
97
Sources: GoTG 1996, and Jaiteh & Saho 2006

The 1993 census, as shown in Table 4, revealed that the Gambia had a population of 1, 038, 145 people and it registered 51% growth rate during the inter census period. It pointed out an addition of 350, 328 people to the country’s population within a decade; a number which was more than the Gambia’s 1963 total population of 315, 486 people and almost doubled the 178, 013 persons added in the decade before.

Figure 6: LGAs by Population Size, 1983 & 1993
                 

From among the LGAs Kanifing and Brikama continued to register growth rates higher than the national average.  As shown in table 4 & figure 6, Kanifing’s population jumped from 101, 504 in 1983 to 228, 214 people in 1993 registering 125% increment in its population during the decade. Accordingly, as shown in figure 7, its share of the total population soared from 14.8% in 1983 to 22.0% in 1993 making it the second most populous LGA in the country. Characteristically, Brikama followed as the second fastest growing LGA with a growth rate of 71%. Having increased its population from 137, 245 in 1983 to 234, 917  people in 1993 which represented 22.6% of the country’s total population for that year, Brikama continued to be the most populous LGA; although, closely followed by Kanifing as shown in figure 7.




Figure 7: LGAs Population as Percentage of 1983 & 1993 Population


The rest of the LGAs, as usual, registered growth rates less than the national average of 51% with Banjul (which for the first time recorded a negative growth rate of -4%) at the end of the scale. Banjul was followed by Kuntaur (17.7%), Mansa Konko (17.9%), Janjangbureh (29%), Basse (39.2%) and Kerewan (39.4%) in that order. Thus, the trend of change observed in 1993 was identical to that of 1983 as Kanifing continued to move swiftly up the rank by relegating both Kerewan and Basse to occupy second position after Brikama. Therefore, Brikama continued to be the most populous LGA in 1993, closely followed by Kanifing, then Kerewan, Basse, Janjanbureh, Kuntaur, Mansakonko and Banjul.

The 1993 census revealed an average density of 97 persons per km2 for Gambia as a whole, implying an addition of 33 persons to the country’s density of 64 in 1983.  Thus, the decade witnessed the highest increase in the country’s density which almost doubled the 17 people increment of the previous decade. From among the LGAs, Banjul continued to maintain having the highest density although its density declined slightly from 3,682 persons per km2 in 1983 to 3,527 persons per km2 in 1993. Banjul was closely followed by Kanifing which has more than doubled its density from 1,336 persons per km2 in 1983 to 3,003 persons per km2 in 1993. Brikama, as usual, followed Kanifing with a density of 133 persons per km2 in 1993; up from 78 persons per km2 in 1983 implying an addition of 55 persons to its density. At the other end of the scale, Mansa Konko added only 6 persons to its density of 34 persons per km2 in 1983 and thus continued to have the lowest density of 40 persons per km2 in 1993. Mansa Konko was followed by Kuntaur with 46, Janjangbureh 62, Kerewan 69, and Basse 75.

Table 5: Area, Population & Density by Local Government Area (LGA) in 2003
Local Government  Area (LGA)
Land Area (sq. km)
Population in 1993
Population in 2003
Decadal % Increase
% of Total 2003 Population
Population Density (Persons/km2)
Banjul
12
42 326
35 061
-17.2%
2.6%
2922
Kanifing
76
228 214
322 735
41.4%
23.7%
4247
Brikama
1 764
234 917
389 594
65.8%
28.6%
221
Mansa Konko
1 618
65 146
72 167
10.5%
5.3%
45
Kerewan
2 255
156 462
172 835
10.8%
12.7%
77
Kuntaur
1 467
67 774
78 491
15.8%
5.8%
54
Janjanbureh
1 428
88 247
107 212
21.5%
7.9%
75
Basse
2 070
155 059
182 586
17.8%
13.4%
88
The Gambia
10 690
1 038 145
1 360 680
31%
100%
127
Source: Jaiteh & Saho 2006



According to the 2003 census, the Gambia's population increased from 1, 038, 145 in 1993 to 1, 360, 680 people as shown in table 5. It indicated an addition of 322, 535 persons during the inter census period, which was slightly less than the 350, 328 people added in the previous decade. Thus, the population grew by 31% making it the lowest decadal growth rate percentagewise for the period under review.

From among the LGAs, as usual, it was only Brikama and Kanifing which registered growth rates higher than the national average of 31%. For the first time, Brikama took over from Kanifing as the LGA with the highest growth rate by recording 65.8% increment slightly less than the 71% recorded in the previous decade. Kanifing recorded a sharp decline in its growth rate from125% in the previous decade to only 41.4%. As it can be seen in figure 9, Kanifing’s  share of the total population marginally increased from 22.0% in 1993 to 23.7% in 2003, whilst that of Brikama increased from 22.6%  in 1993 to 28.6% in 2003.

Figure 8: LGAs by Population Size, 1993 & 2003
As usual, the remaining LGAs registered growth rates less than the national average of 31%. Among them Banjul continued to be at the bottom with a growth rate of negative 17.2%. Banjul was followed by Kerewan with a growth rate of 10.5%. Mansa Konko followed with a growth rate of 10.8%; Kuntaur 15.8%; Basse 17.8% and Janjangbureh 21.5% in that order. Hence, Brikama maintained its position as the most populous LGA and was followed by Kanifing in second place with an increasing margin. Basse followed in third place by relegating Kerewan to fourth. The remaining LGAs followed with Janjanbureh in fifth place; Kuntaur, sixth; Mansa Konko, seventh; and Banjul, eight.

Figure 9: LGAs Population as Percentage of 1993 & 2003 Population

The density of Gambia’s population also increased by 30 persons from 97 persons per km2 in 1993 to 127 persons per km2 in 2003 which was slightly less than the 33 persons added during the previous decade. At the LGA level, Kanifing surpassed Banjul as the LGA with the highest population density for the first time, it added 1,244 people to its density of 3,003 people per km2 in 1993; thus, recording a density of 4,247 people per km2 in 2003. Banjul followed with a density of 2,922 down from 3,527 in 1993 recording a reduction of 605 people per km2 in its density. Brikama followed with a density of 221 persons per km2 recording an addition of 84 persons per km2 to its density during the decade.

Routinely, the rest of the LGAs recorded increments less than 30 persons per km2. Among them Mansa Konko (45) was at the end of the scale, it added only 5 persons to its density of 40 persons per km2 during the decade. Kuntaur (54) followed Mansa Konko as usual, and then Janjangbureh came after Kuntaur (75), which was followed by Kerewan (77) and Basse (88).

As shown in map 2, the Gambia’s population distributional pattern has changed strikingly from 1963 to 2003. In 2003 the Gambia’s population has not only more than quadrupled to 1, 360, 681 in four decades, but has developed such an uneven distribution that the two Local Government Areas of Brikama with 389, 594 people, and Kanifing with 322, 735 people accounted for 52.4% of the 2003 total population, although they jointly occupied only 17.2% of the total land area. This change becomes more remarkable when 1963 data is referenced as they accounted for only 21.5% of the country’s population or 67, 601 people. This reveals that the Gambia’s population is not only characterized by rapid growth, but is increasingly skewed in its distribution.  Factors responsible for these changes important as they are fall beyond the scope of this paper which restricts itself to analyzing the changes in the pattern of distribution.

Although all the remaining LGAs registered a drop in their share of the total population from 1963 to 2003 as indicated by the histograms in map 2, it was more outstanding for Banjul and Mansa Konko, which interestingly are the Adjacent LGAs to Kanifing and Brikama respectively. Banjul’s share of the total population plummeted from 8.8% in 1963 to 2.6% in 2003, whilst that of Mansa Konko slumped from 10.8% in 1963 to 5.3% in 2003. Kuntaur, which had increased its share of the total population from 9.2% in 1963 to 9.7% in 1973 as shown in map 2, also recorded a significant drop in its proportion of the Gambia’s total population from 9.2% in 1963 to 5.8% in 2003. Similarly, Kerewan’s proportion of the total population dropped significantly from 20% in 1963 to 12.7% in 2003. Basse and Janjanbureh LGAs also recorded a continuous drop in their share of the Gambia’s total population from 18.4 and 11.3 percentage points in 1963 to 13.4 and 7.9 percentage points in 2003 respectively.

A comparison of the size of the Local Government Areas as percentage of the Gambia’s total land area with their population as proportion of the country’s 2003 total population would revealed the skewed nature of the distributional pattern of the Gambia’s population. For example, Kerewan being the largest LGA with 21.1% of the country’s total land area accounted for mere 12.7% of the country’s total population. Basse, which followed with 19.4% of the total land area accounted for just 13.4% of the total population. Brikama, the third largest LGA, with 16.5% of the total land area accounted for 28.6% of the 2003 total population and was the most populous LGA. Mansa Konko with 15.1% of the total land area was the fourth largest LGA; yet, it accounted for only 5.3% of the total population. Similarly, Kuntaur, the fifth largest LGA with 13.7% of land area accounted for mere 5.8% of the total population. Janjanbureh with 13.4% of the total land area was the sixth largest LGA and accounted for 7.9% of the total population. Kanifing, the seventh largest LGA, with just 0.7% of the total land area accounted for as much as 23.7% of the total population. Banjul, the smallest LGA, with only 0.1% of the total land area accounted for 2.6% of the country’s total population in 2003.
















Map2: Distribution of the Gambia's Population by Local Government Area

Analyzing the Changing Pattern of the Gambia’s Population Distribution Using Lorenz Curve
The Lorenz curve is a graphic depiction of distribution initially devised to indicate concentrations of income or wealth, but is now widely used in population geography to measure population concentrations when information about an area is available for equivalent areal units like LGAs. It involves plotting cumulative percentages of population of Local Government Areas against cumulative percentages of the areas of the LGAs. Units of areas are ranked according to the density of population in ascending order and then populations and areas of these units are totalled to give cumulative percentages of area and population as seen in table 6. The cumulative percentages of population are then plotted against the cumulative percentages of area and the points are joined together to form a ‘curve’ as seen in figure 10. If the curve follows a diagonal, it would indicate an even distribution of population; that means each Local Government Area contains a proportion of the Gambia’s total population equalled to its proportion of the country’s total land area. Usually, there is a considerable departure from this and the greater the curvature the greater the unevenness of the population distribution. The variation between the Lorenz curve and the diagonal is called the inequality gap and is equivalent to the index of concentration referred to as concentration index (CI).

The Concentration Index (CI) is the deviation of the curve from the diagonal line and it is the proportion of inequality in the distribution of population in relation to the area. A concentration index (CI) of zero is the diagonal on the Lorenz curve.  On the contrary, a concentration index (CI) of hundred indicates perfect concentration, which means that the entire population is confined in a single geographical unit. For instance, if the whole population of the Gambia is found in only one of the eight Local Government Areas, then CI would be equal to 100. Thus, the concentration index shows the percentage of population that should be redistributed to produce a perfect balance between the area and population. As shown in table 6, 13.1% of the Gambia’s population should have been redistributed to attain a perfect balance between the country’s population and area; whereas in 2003, this number had almost tripled to 37.6%. The Lorenz curve at figure 10 reveals this fact.

.
The concentration index (CI) is algebraically expressed as CI=1/2∑ |x-y| and it is equal to the maximum of |X-Y|. In table 6, 1963 population is represented by ya; and 2003 population by yb. Hence, for the year 1963, CI = 1/2∑ |x-ya| = ½(26.2) = 13.1. This is equal to the maximum of |X-Ya| with the corresponding values of 82.7 for X, and 69.7 for Ya, see table 6. For the year 2003, CI = 1/2∑ |x-yb| = ½(75.2) = 37.6, which is equal to the maximum of |X-Yb| with the corresponding values of 82.7 for X, and 45.1 for Yb as shown in table 6.


Table 6: Cumulative percentage of total land area and cumulative percentages of the total population for 2003 and 1963

Local Government  Area (LGA)
% Land Area
(x)
% of
1963 Population
(ya)
|x-ya|
Cumulative % Land Area
(X)
Cumulative % of 1963 Population
 (Ya)
|X -Ya|
% of 2003 Population
(yb)
|x-yb|
Cumulative % of 2003 Population
 (Yb)
|X-Yb|
The Gambia
100%
100%




100%



Mansa Konko
15.1%
10.8%
4.3
15.1
10.8
4.3
5.3%
9.8
5.3
9.8
Kuntaur
13.7%
9.2%
4.5
28.8
20.0
8.8
5.8%
7.9
11.1
17.7
Janjan
bureh
13.4%
11.3%
2.3
42.2
31.3
10.9
7.9%
5.5
19.0
23.7
Kerewan
21.1%
20.0%
1.1
63.3
51.3
12
12.7%
8.4
31.7
31.6
Basse
19.4%
18.4%
1.0
82.7
69.7
13
13.4%
6.0
45.1
37.6
Brikama
16.5%
17.6%
1.1
99.2
87.3
11.9
28.6%
12.1
73.7
25.5
Kanifing
0.7%
3.9%
3.2
99.9
91.2
8.7
23.7%
23.0
97.4
2.5
Banjul
0.1%
8.8%
8.7
100
100
0
2.6%
2.5
100
0

                                         ∑|x-ya| = 26.2                                                  ∑|x-yb| = 75.2
                                         CI=1/2∑|x-ya|                                              CI = 1/2∑|x-yb|
                                             = 13.1                                                            = 37.6