Jacob F. Olorunfemi1* and Irewolede Fashagba1 1 Department of Geography and Environmental Management, University of Ilorin, Ilorin, Nigeria. * Corresponding author: [email protected] A NOVEL methodological approach GEOGRAPHY OF Estimating URBAN Population 17 IN NIGERIA Abstract. The primary source of population data in Nigeria is the census despite its inconsistency. Consequently, efforts made to estimate population from such census figures and sometimes vital registration system has proved inadequate because of diverse problems. This study is aimed at developing a technique of population estimation in Nigeria using symptomatic data. The data for this study were collected through survey method, immunization and school enrolment data were collected from the Expanded Programme on Immunization and Ministry of Education, respectively. The average number of people per house or crowding index (CI) for Kabba was combined with immunization and school enrolment to establish a relationship which was subsequently used in regression analysis to estimate population. The results show that the population of Kabba and Kogi State were 70,870 and 4,230,382, respectively. The study recommended that the model can be used for population estimation in Nigeria and in places that have similar population data generation problems. Key WORDS: Population, Symptomatic, Census, Estimate, Crowding Index Citation: Jacob F. Olorunfemi and Irewolede Fashagba (2018) A novel methodological approach of Estimating Urban Population in Nigeria. Geography, Environment, Sustainability, Vol.11, No 2, p. 17-28 DOI-10.24057/2071-9388-2018-11-2-17-28 Introduction creates different settlement pattern on the land scape. Oftentimes, a very small village The census is the main source of population soon becomes so big, covering several data. Evidence from literature suggests that hectares of land within a few decades. The population data collection dates back to inhabitants of such areas are faced with 1789 in Nigeria, but there has never been poor roads, poor/ inadequate housing, any consistency in the process. Despite this, inadequate water supply, poor power population data have remained the main supply, as well as poor dietary intake, among ingredient on which every social, economic others. and spatial development planning is based. The need for population data is felt more In ameliorating such situations, researchers than ever before in Nigeria because of rapid have concerned themselves with how to urbanization. Previous studies revealed that unveil population distribution pattern, increases in population at various times in dynamics, as well as the composition and spatially defined areas of the world usually structure of the population. These and many GEOGRAPHY, ENVIRONMENT, SUSTAINABILITY 02 (12) 2018 other effects that often result from man to encourage education through school environment-relation have constituted the enrolment made attendance of primary geographers’ domain of study. Most often, school and junior secondary school free data on the number of people living at such and compulsory for children of school age. places are generated through the census Hence, the enrolment rate improved and and where not available through indirect actually increased. The present effort is an techniques. attempt at evolving a population estimation model based on immunization and school GEOGRAPHY The usual and most common method is enrolment. If successful, it could become through projections that are based on the a source of population data generation for 18 application of the annual growth rate index local and urban development planning and through the use of indirect techniques purposes in Nigeria. of population estimation (Ekanem 1972; Afolayan 1978; Ayeni 1980; Olorunfemi 1981, THE STUDY AREA 1984, 2005; Mba 2006; Akanbi 2006). Nigeria’s total population figures had been estimated This study was carried out in Kabba, a town in from tax records at various times in the past Kabba/Bunu Local Government Area (LGA). (Adediji 2011). About the middle of the The LGA is located on Latitudes of 70 45’ and 20th century, the method of generating 8028’ North and Longitudes of 60 5’ and 60 population data shifted to making estimates 30’ East. The Local Government is bounded from fertility and mortality records. This by Yagba West, Mopamuro and some parts shift can best be illustrated by Ayeni’s work of Ijumu Local Government to the West, the on Katsina (Ayeni 1980). But, as at 2014, southern part of Ijumu Local Government registration of births in Nigeria covered only and Okehi Local Government to the South, 42% of the rural dwellers (NPC 2014). Thus, Lokoja Local Government to the East, Kogi using data from this source would appear Local Government and Kwara State to the unsuitable because of low coverage. North (Fig. 1, 2). Kabba in recent times has merged with some of the settlements in its The challenges of the techniques above suburbs and a number of people from the require that research must continue to settlements in the neighborhood migrated find improved techniques of population to the town. This has substantially increased estimation in the absence of the actual the physical expansion of the town to make census. It is for this reason that the it worthy of study. possibility of using immunization and school enrolment data becomes relevant in Nigeria Kabba has three political districts (Kabba, because immunization of children has a Odolu and Aofin) and seven political wards wide coverage and its documentation since namely: Aiyetuju/Kakola, Odolu/Fehinti, it was introduced in 1979 has been good. It Ayewa, Asuta, Oke-koko Bolorunduro and should be recalled that immunization was Otugunbe. The town is situated at about introduced to address the prevalent high 78km away from Lokoja, the Capital of Kogi death rate of children in Nigeria. Among a State and about 130km from Abuja, the number of vaccines that were injected on Federal Capital Territory of Nigeria. Kabba both children and pregnant women is BCG. people are Yoruba by tribe. They are believed The BCG usually has the highest coverage to have migrated from Ife in Osun State over because it is first injected at birth, while 900 years ago. Kabba, being the primate others are injected at various stages of life town in the Kabba/Bunu Local Government thereafter. Area, has attracted several other tribes from other settlements. The emigrants are mostly Primary and secondary school enrolments Ebira, Igbo, Tikfi and Hausa. in Nigeria have received wider coverage and good documentation in recent times The 1991 population of Kabba was 36,124, because of the several efforts made by while that of the local government was government to encourage secondary 79,276 (NPC 1991). However, the 2006 school education. Government’s quest population census did not release the total Jacob F. Olorunfemi and Irewolede Fashagba A novel methodological ... GEOGRAPHY 19 Fig. 1. Map of Kogi State Showing Kabba/Bunu Local Government Area (Kogi State Lands and Survey 2014) Fig. 2. Map of Kogi State Showing Kabba/Bunu Local Government Area (Kogi State Lands and Survey 2014) GEOGRAPHY, ENVIRONMENT, SUSTAINABILITY 02 (12) 2018 population of Kabba, rather it gave the to have some fairly big ones for this study. total population of the local government as The total number of houses in the study area 144,579 (NPC 2006). Even at this, evidence of was obtained from direct house counting the spatial expansion of Kabba suggests that conducted in all the quarters. Although the population has greatly increased. All the the approach was cumbersome, it was the hitherto undeveloped spaces in the South, available option. Besides, direct counting South-West, West and North-West axes of of house may be the most appropriate Kabba have been developed and occupied technique of population estimation in an GEOGRAPHY by residential houses. emerging urban centre such as Kabba, especially at the modeling level. Ordinarily 20 Kabba is strategically situated in a low land, if town planning records were reliable, this but surrounded by hills (Fig. 3). These hills would have been a faster source of house are low-high lands of 305-610 meters in number. Aerial photographs or large-scale height. Kabba is underlain by Igneous and satellite data if available would also have Metamorphic rocks of the basement complex provided a faster source of data on house with Out-crops as massive ridges and rocky numbers. hills extended over a greater part of the area (Udo 1975). This landform is characterized In selecting the samples, 420 copies of a by smooth and rounded Inselberg hill questionnaire were administered on the particularly, in the West and North of Kabba. household heads. Of these, 411 which accounted for 10% of the household heads MATERIALS AND METHODS in Kabba (NPC 2010) were returned valid. The 10% sample, of course, satisfies the Both primary and secondary data were used required percentage for social science for this study. Data on immunization were research particularly, in demographic studies collected from the Expanded Programme on (Oludoyi 2007; Oriola 2002). A systematic Immunization (EPI), the National Programme sampling technique was employed to select on Immunization (NPI), and the Ministry of the samples from the sixteen quarters. Health. Also, data on primary school and junior The first sample was randomly selected secondary school enrolments were collected in every first street in the quarter, while from the Ministry of Education, National subsequent samples were selected from Bureau of Statistics and United Nations every fourteenth house until the last sample Education’s Fund (UNICEF). The primary data in each quarter was secured. The Product that includes demographic characteristics, Moment Correlation Coefficient was used to number of houses and household structure determine the degree of association among were collected through the survey method the paired dependent (population) and using questionnaire administration. the independent variables (immunization, primary school and junior secondary school The existing 34 quarters in Kabba town _ (1) were grouped into 16 quarters.