KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY
POST INUNDATION EFFECTS OF BUI HYDRO ELECTRIC DAM ON THE LARGE MAMMALS IN THE BUI NATIONAL PARK IN THE BRONG AHAFO REGION OF GHANA
BY
PAUL KUUBETERERO DERY (INDEX NO. PG8937313)
THESIS SUBMITTED TO KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY IN FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF MASTERS OF SCIENCE IN ENVIRONMENTAL SCIENCE
SEPTEMBER, 2016
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DECLARATION
I, Paul Kuubeterero Dery, do hereby declare that this project work is my work and that to the best of my knowledge and belief, it contains no materials previously published or written by another person nor material which to a substantial extent has been accepted for the award of any, degree or diploma in Kwame Nkrumah University of Science and
Technology or in any other institution of higher learning except where due acknowledgement has been made in the text.
STUDENT: PAUL KUUBETERERO DERY
INDEX NUMBER: PG8937313
SIGNATURE ..…………………….………..……...
DATE ……………………….…….…....……
SUPERVISOR: DR. SAMUEL AIKINS
SIGNATURE: ………………………….……..………
DATE …………………………………………
HOD: DR. M. G. ADDO
SIGNATURE: ………………………………………….
DATE: ………………………………………….
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ACKNOWLEDGEMENTS
My greatest gratitude goes to God Almighty, the Supreme Being, the Beginning and the
End, Who took care of me and saw me through this programme. My heartfelt thanks go to Dr. Samuel Aikins, my supervisor, who provided excellent guidance and gave me incredible patience all throughout this study. I am grateful to Mr. Eric Appiah Agyapong who also stood by me and provided the necessary encouragement I needed in this study.
I am also grateful to Mr. Japheth Roberts who despite his tired schedules sacrificed his time and job to make this study a success. To Mr. Samuel Kwaku Obeng, who also, shared the most precious part of his time with me in this study and was always ready for me anytime I called. To my Regional Manager, Mr. C. K. Haizel Abaka, wildlife division (FC), who gave me the necessary encouragement and motivation in this study and inspite of his busy schedules, bought time to read through this work and made the necessary inputs and corrections. Papa, I am grateful. I also express my sincere heartfelt appreciation to my brother, Mr David Kpelle for his enormous contribution and support.
To my immediate boss, Mr. Samuel Akonor-Darko, who made available the necessary human and material resources for this study. I am grateful. And to the entire staff of Bui
National Park, who helped me with the field work particularly the field staff, and
Messrs. Ofori James and Nimo Samuel, who also helped me with the administration of the questionnaires in this study. I am grateful.
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DEDICATION
I dedicate this research to my lovely mother, Mrs. Francisca Dery and my caring uncle,
Mr. Honorius B. Dery for their immense contribution in diverse ways to this level in my education.
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ABSTRACT
Assessment of the post inundation effects of Bui Hydro Electric Dam on the large mammals of the Bui National Park was carried out from October, 2014 to September,
2015. The construction of the Bui Hydro-Electric Dam at the Bui gorge was expected to inundate about 21% of the core zone of the Bui National Park. The loss of habitat, led to displacement of wildlife within this zone. Descriptive research design involving qualitative, quantitative and observational methods was used for this study. This was based on two sources of data, primary and secondary. Questionnaires were administered and the total number of respondents was 398, which comprised 350 local community members and 48 staff of Bui National Park. Line transects were walked in the Bui
National Park and the large mammals sighted were identified at the species level and counted. There was no change in species diversity from the pre-through to the post inundation, as the diversity of 18 species remained the same. However, inundation caused a drop in abundance. The inundation decimated populations of some large species, besides causing a major habitat loss but those that survived moved to safe areas.
The study however recorded significant recovery in large mammal abundance notably the Hippopotamus, which had recovered (from 69 during inundation to 327p after inundation) almost to the year 2010 (335 the highest) abundance level pre-inundation.
High number of distressed animals were rescued and relocated to similar but safer habitats within the park by the Bui National Park rescue team. The inundation significantly affected the large mammals within the Bui National Park (P < 0.05). It is recommended that the large mammals be monitored to give updates of abundance trends
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to inform the management of the Park. The Bui National Park should be expanded to accommodate and ease mobility of displaced mammals as a leverage to increase the abundance and diversity of the mammals.
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TABLE OF CONTENTS
Contents Pages
DECLARATION ...... ii
ACKNOWLEDGEMENTS ...... iii
DEDICATION ...... iv
ABSTRACT...... v
CHAPTER ONE ...... 1
INTRODUCTION ...... 1
1.1 Background of the study ...... 1
1.2 Problem Statement ...... 3
1.3 Objectives of the Study ...... 4
1.4 Research Questions ...... 5
1.5 Research Hypothesis ...... 6
1.6 Significance/Justification of the Study ...... 6
CHAPTER TWO ...... 8
LITERATURE REVIEW ...... 8
2.1 Environmental Impacts ...... 8
2.1.1 Environmental science ...... 8
2.2 River Ecosystems and its Impact of Dams ...... 13
2.2.1 Criticism about large dams ...... 15
2.2.2 Upstream impact of large dams ...... 16
2.4 Importance of Mammals to Biodiversity ...... 17
2.5 Effects of Dams on Human Life ...... 18
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2.6 Effects of Dam Construction on Species ...... 21
2.7 Inundation effect on Wildlife ...... 24
2.7.1 Short Term Effects of Inundation on Wildlife ...... 25
2.7.2 Long term Effects on Wildlife ...... 26
2.7.3 Effects of Inundation on Hippopotamus ...... 27
2.7.4 Effects of Inundation on Ungulates ...... 28
2.7.5 Effects of Inundation on Primates ...... 29
2.8 Temporary Effects on Wildlife during Construction ...... 29
2.8.1 Disturbance of wildlife ...... 30
2.8.2 Effects of noise, traffic and other human activity ...... 30
2.8.3 Increased hunting pressure during construction and inundation ...... 31
CHAPTER THREE ...... 33
METHODOLOGY ...... 33
3.1 The Bui hydropower dam ...... 33
3.2 Research Design ...... 37
3.3 Data Sources ...... 39
3.4 Population ...... 40
3.4.1 Banda-Ahenkro District ...... 40
3.4.2 Bole District ...... 40
3.5 Sampling Plan and Sample Size ...... 42
3.6 Data Collection Method ...... 43
3.7 Validity and Reliability...... 44
3.7 Data Analysis ...... 45
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CHAPTER FOUR...... 46
RESULTS ...... 46
4.1 The diversity and abundances of large mammals in the Bui National Park before,
during and after the inundation ...... 46
4.2 Demographic Profile of the Respondents ...... 54
4.3 Perception of the State of Mammals in Bui National Park ...... 56
4.4 Further Analysis ...... 58
CHAPTER FIVE ...... 59
DISCUSSION ...... 59
5.1 Discussion of the Study ...... 59
5.2 Conclusion ...... 69
5.3 Recommendations ...... 70
REFERENCES ...... 71
APPENDIX A ...... 83
Research Questionnaire for inhabitants of Bui National Park ...... 88
Research Questionnaire for Staff and Management of Bui National Park ...... 90
Management Questionnaire ...... 92
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LIST OF FIGURES
FIGURE 3.1: LOCATION OF THE BUI PROJECT ...... 34
FIGURE 3.2: LAYOUT OF THE PROJECT ...... 35
FIGURE 3.2: THE MAIN COMPONENTS OF THE BUI PROJECT ...... 37
TABLE 3.1 RELIABILITY STATISTICS ...... 44
FIGURE 3.2 TRUE DIVERSITY ...... 50
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LIST OF TABLES
TABLE 2.1: TYPE OF ECOLOGIES [JONG, 2002] ...... 8
TABLE 3.1 RELIABILITY STATISTICS ...... 44
TABLE 4.1: TOTAL SPECIES ABUNDANCE ...... 46
TABLE 4.2 DIVERSITY INDICES ...... 49
TABLE 4.3: DEMOGRAPHIC PROFILE OF THE LOCAL COMMUNITIES ...... 53
TABLE 4.4: DEMOGRAPHIC PROFILE OF THE STAFF...... 54
TABLE 4.5: WEIGHTED RANK MEAN OF THE VIEWS OF INHABITANTS ON THE STATE OF
MAMMALS AFTER BUI DAM‟S CONSTRUCTION ...... 56
TABLE 4.6: WEIGHTED RANK MEAN OF THE VIEWS OF STAFF ON THE STATE OF MAMMALS
AFTER THE INUNDATION ...... 57
TABLE 4:7 PAIRED T-TEST AND CONFIDENCE INTERVAL FOR ABUNDANCES OF MAMMALS
BEFORE AND AFTER BUI DAM INUNDATION ...... 58
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CHAPTER ONE
INTRODUCTION
1.1 Background of the study
Freshwater is an essential natural resource on which all living things depend. Dams have been used for thousands of years to regulate river flows and ensure adequate supply of water during dry periods. In the future, as human population increases and water consumption rises many people believe there will be a need for more dams (McCartney, Sullivan & Acreman, 2001).
However, in recent years, proposals for new dams have, in many places, aroused intense opposition (McCartney, et al., 2001). There are many social and economic arguments used against dams, but underpinning many of these arguments is the fact that dams, particularly large dams, produce major ecological changes in river ecosystems (McCartney, et al., 2001).
Dams have impacts on both upstream and downstream ecosystems. They constitute obstacles for longitudinal exchange along rivers and disrupt many natural environmental processes. Flooding upstream of dams results in the permanent destruction of terrestrial ecosystems through inundation. All terrestrial plants and animals disappear from the submerged area. Reservoirs trap waterborne materials including sediment and obstruct migration pathways for some aquatic species. At the downstream there are changes in flow regime, sediment transport and water temperature and quality. Many of these changes are immediate and obvious. However, others are gradual, subtle and more difficult to predict. For example, changes in thermal regime, water quality and land-water interactions result in changes in primary production, which in turn has long-term implications for mammals, fish and other fauna higher up the food chain. Dams may cause changes in ecosystems at great distances from the dam. For example, changes in sediment
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transport results in changes in river, floodplain and even coastal delta morphology sometimes many hundreds of kilometers from the site of the dam.
Since independence in 1957, Ghana has constructed large and small scale dams to generate electricity, supply water for domestic and industrial uses and to irrigate agricultural lands to boost food production. However, as in other parts of the world, the benefits of these projects have not gone without considerable social, economic and environmental costs. Due to these fears expressed by stakeholder and NGO lobbyist groups, the decision to build Bui Dam has been increasingly contested to the point where the future of large dam building in Ghana is in question. The enormous investments and widespread impacts of Akosombo and Kpong dams have brought about conflicts as a result of the socio-economic and environmental impacts of large dams - both those in place and those on the drawing board, making large dams construction one of the most hotly contested issues in participatory project planning today (Anane, 1999;
Tsikata, 2004).
The response of river ecosystems to dams are multiple, varied and complex. Consequently, in attempting to determine the effect of dams on ecosystems there is a requirement for large amounts of data relating to: hydrologic characteristics of the river; water quality; geomorphological characteristics; aquatic biota and their habitat; riparian vegetation and associated fauna and the direct use of the resources of the river and its floodplain by local people.
There is a need for fundamental research linking changes in abiotic processes caused by dam construction to changes in ecology, particularly in tropical climates where much of the remaining
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potential for new dams reside, but where very little research has been conducted to date (Anane,
1999; Tsikata, 2004).
1.2 Problem Statement
Attempts to build a large dam on the Black Volta River near the village of Bui in the Brong-
Ahafo Region of Ghana have existed for more than fifty years. Though several feasibility studies were undertaken, frequent changes in government and difficulty in attracting financial assistance over the years prevented its implementation in times past.
The climatic conditions over the past years had not been the best and that had caused reduced water inflow into the Akosombo dam. The low level of water in the Akosombo damwhich occasioned growing level of mismatch between demand and supply of power necessitated the rationing of power in 2006. This compelled government to find an alternative means of increasing Ghana's electricity production both in the short and long terms hence the government quickly adopted a two pronged approach to expand the power sector; through sectorial policy on thermal power production and hydropower generation. Unfortunately, due to high increases in crude oil import bill in 2007, government thought it prudent to pursue the latter to meet the countries growing power demand by immediately sourcing funding from the Export - Import
Bank of China for the construction of Bui Dam.
Notwithstanding this laudable idea of additional power generation, the Bui Dam Project was projected to have both severe environmental and social consequences (Ghana Dams Forum
(GDF), 2008; International Rivers Network (IRN), 2002). The 444km2 reservoir with the capacity of 400MW of electricity was going to displace about 1,216 people (Coyne et Bellier,
1995 as cited in Fink, 2005) Additionally as large proportion of the dam was within the Bui
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National Park, the unique gallery forest as a habitat for some forest animal species and most of
Ghana‟s remaining hippopotamus populations in the park would be threatened by the project.
Regrettably, due to its political appeal, less attention was paid to these concerns raised by NGOs and international lobbyist groups.
However, the Bui dam has been finally built after all the challenges over the years. The dam is expected to contribute to meeting Ghana's medium to long term energy needs as it will compliment and provide viable, reliable and economical source of energy (Energy Commission
(EC), 2004).
The position of this research is that, not enough scientific consideration was given to the environmental repercussion the dam would create on the Bui National Park with regard to the loss of its pristine biodiversity. There is therefore the need to assess the effect this would have on the general ecosystem as a direct consequence of the dam and its attendant inundation of the Bui
National Park.
1.3 Objectives of the Study
The main objective is to assess the post inundation effects of Bui Hydro Electric Dam on large mammals in the Bui National Park.
Specific Objectives are to:
find out the perception of the people in the catchment area about the large mammals in
the Bui National Park before, during and after inundation
determine the large mammals‟ diversity in the Bui National Park before, during and after
inundation.
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determine the large mammals‟ abundance in the Bui National Park before, during and
after inundation.
determine the mortality of large mammals in the park before, during and after inundation.
compare the current state of large mammals and respective abundances to pre and during
inundation era
1.4 Research Questions
In view of the above discussion, five questions are posed which the study addressed as:
i. What is the variation of the perception of the people in the catchment area about the large
mammals in the Bui National Park before, during and after inundation?
ii. What is the variation of large mammals‟ diversity in the Bui National Park before, during
and after inundation? iii. What is the variation of large mammals‟ abundances in the Bui National Park before,
during and after inundation? iv. What is the variation of the mortality of large mammals in the Bui National Park before,
during and after inundation?
v. What is the variation of the current state of large mammals and respective abundances to
pre and during inundation?
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1.5 Research Hypothesis
i. There is a significant variation of the perception of the people in the catchment area about
the large mammals in the park before, during and after inundation
ii. There is a significant variation of species diversity in the park before, during and after
inundation iii. There is a significant variation in the abundance of the various species of the large
mammals before, during and after inundation iv. There is a significant variation in the mortality of large mammals of the park before,
during and after inundation
v. There is a significant variation of the current state of large mammals and respective
abundances to pre and during inundation
1.6 Significance/Justification of the Study
A study such as this is necessitated as a key monitoring and management planning function.
Some of the projected impacts of the dam construction on biodiversity and wildlife as stated in the Environmental and Social Impact Assessment Statement are;
Wildlife mortality due to drowning during the inundation period
Dislocation of wildlife from previously used home-ranges
Stresses on the social structure of ungulates
Isolation and stranding of primates.
With the completion and current operation of the Bui Dam, it is of the highest importance that a study be conducted to assess the impact on diversity of large mammals. The Impact assessment of Bui dam referred to Lake Kariba and the increase in large mammal population post inundation
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as a basis for describing the projected impacts of the Bui dam as moderate. It is therefore necessary to assess the diversity and population variation post inundation as this would greatly influence management planning for the Bui National Park; by providing vital information on the population trends while serving as a guide for future management intervention.
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CHAPTER TWO
LITERATURE REVIEW
2.1 Environmental Impacts
The ecological impact of the project follows the approach of Jong (2009). Those impacts are already described in the environmental and social impact assessment of the project but in a linear approach. The categories of ecologies as described by Jong are drawn in Table 2.1.
Table 2.1: Type of Ecologies [Jong, 2002]
Type of Ecology Naming abiotic Naming biotic
Environmental science Environment Human society
Autecology Habitat Population
Synecology Biotope Life community
Cybernetic ecology Abiotic variation Biotic variation
System dynamics ecology Ecotope Ecological group
Chaos ecology Opportunities Individual strategies for survival
2.1.1 Environmental science
The Environmental science is an anthropocentric approach that positions the impacts of a construction work on human society and human environment on top of the list. It is mainly concerned aboutthe loss of human residence and communities due to temporary or permanent inundation of large areas behind the dam. Part from residential losses that can be replaced elsewhere – sometimes some hundred meters higher than before as in the three Georges dam in
China – this approach is also taking into account the possible losses of cultural heritage
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(monuments, natural shelters, etc.) and the expected differentiation in working opportunities and working conditions that the project itself and the new environment will rise.
The EISA for the Bui project foresees that the area that will be permanently inundated is predominantly vegetation comprising about 50% grassland, 25% savannah woodland and 25% water and riverine gallery forest. It also includes the area of six villages providing homes to about 1,360 people (127 households). These villages are predominantly fishing and farming communities. Another farming village, Dokokyina of 350 villagers will not be flooded but will require relocation and four more villages with a total 7500 people will also not be directly affected but will lose forest and farm land. Land inundated by the reservoir will include domestic, business and community facilities within villages together with farming, fishing, forest and hunting grounds around them. Cultural sites including ancestral villages no longer occupied and sites associated with the occupied villages (graves, churches, etc.) will also be lost.
Autecology
As described in Jong (2002), “autecology concerns populations of one species at a time within their „habitat‟.” Or else autecology examines each species and population individually without considering any other population around or their interrelations and how it might be affected. So some indications throughout the environmental and social impact assessment for the project are concerning the reasons that will mainly affect habitats independently of their neighboring environment.
Impacts on aquatic ecology where in first hand short-term impacts due to the construction and inundation will cause the slow change of flowing water biological communities to acquire
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lacustrine characteristics. Species that prefer shallow habitat are likely to colonize the periphery of the reservoir, and others that require moving water will disappear or persist as relict populations in the headwaters of the reservoir. Long-term impacts are also expected with the main source being the transition from a flowing water environment to a lacustrine aquatic community. This will increase the shoreline to 500km and introduce small islands, an effect that will create a new littoral zone across the shorelines that will cause an increase in aquatic and semi-aquatic vegetation (Jong, 2002).
The project will also cause a total loss of 23,450 ha of riverine forest. An impact that will lead to vegetation loss and disturbance that will alter the area, shape and continuity of remaining vegetation patches within the landscape, altering the floral and faunal species composition, and possibly rendering the fragmented ecosystems unable to support the species communities found in undisturbed ecosystems.The Inundation of the reservoir will also result in drowning of some terrestrial fauna unable to escape from flooded forest, grassland, and savannah woodland habitats. Lastly, the reservoir will reduce habitats for wildlife species that require flowing water
(some insectivorous birds and bats) but increase foraging habitat for wildlife that prefer still or slow-moving waters such as waterbirds (Jong, 2002).
Synecology
Jong describes synecology as the ecology that is concerning the community of different species in the same „biotope‟. So it is the examination of a life community as a whole instead of specific animals and plants. Bui hydropower dam causes diverse impact on various families of species such as ungulates, primates, birds and fishes.
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Ungulates such as kob and buffalo that migrate seasonally in order to meet food and water availability are likely to benefit from inundation since there is likely to be permanent water supply all year round. This would affect the usual migration patterns and most likely will lead to population increases. Even if inundation will cover a huge area of grassland habitats the increased water availability will increase the value of remaining grasslands as habitat for grazing mammals and provide a year-round source for drinking. Primate species richness typically declines proportionately with habitat patch size. There are studies though indicating that primates of the project might be able to move to nearby habitats as these are not already at carrying capacity (Jong, 2002).
Bird species that are habitat generalists will be less affected than the habitat specialists that will be forced to move to nearby habitats within the area but the quality and availability of suitable habitats is not yet known. Fish will meet a dramatic increase in number during the first years after inundation. Over time though this increase will stabilize and feeding fish species are likely to diminish in numbers due to sedimentation on the reservoir bottom and subsequent loss of their benthic food supply.
Cybernetic Ecology
Cybernetic ecology emphasizes at the boundaries between spaces instead of the character of spaces itself. The evolution of these boundaries through time is under discussion and design of these boundaries in space is something that cybernetic ecology, through its main expressionists,
Aldo van Eijck and Chris van Leeuwen is claiming to urban and architectural designers.
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Here in the examined ecosystem the boundaries in space are clearly defined and formed by the dam itself. It is through a violent division that cannot easily be absorbed by nature. The dam draws a boundary between upstream and downstream of a river in a place where for thousands of years there was none and part from these boundary conditions that must create a new equilibrium there is a need for a new balance between the new steady situation provided by the new formed lake conditions and the existing system that is totally formed on a basis of a river ecosystem.
Even this steady situation though is always under questioning as a simple decision for excess or reduced water flow can distract the balance and form a new situation where the ecosystem might need to readapt (Jong, 2002).
System dynamics ecology
In system dynamics the boundaries of an ecosystem are observed. The inside is considered a
„black box‟ and measurements and observations depended on the external conditions indicate a behavior that can be expected in other situations. An area around a hydroelectric dam can never be considered as a regular ecosystem. The project itself causes a progressive transformation of the area from a river to a lake ecosystem. The new situation though cannot be compared to the steady equilibrium of common lake as in terms of seasonal changes the ecosystem faces enormous inputs and outputs of energy that in many cases are taking place under human control.
Chaos ecology
Chaos ecology stresses the unpredictability from minor earlier events. It examines whether the stress-tolerators, competitors or ruderals are promoted and if the capacity of the system is as such to absorb some random event or it is too homogeneous. In order to meet the highest tolerance
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limits the ratio of variety and quality must be meeting optimal levels (Jong, 2002).
The new situation that will be formed after the completion of the project and the inundation of the reservoir will provide a totally steady situation for the area in contrast with the constant energy flow that existed beforehand. This stability will give space to species to adapt to the new situation and will bring new inhabitants that may cause instability to the system, as there might be a newborn competition among the new and the old ones. On the other hand the lake fluctuation and the increased shorelines will create new room for species that are tolerant to this constant change and can act as stress-tolarators for the whole ecosystem. Although the extreme barriers are set, the dam itself to the upstream and downstream parts of the system provokes the decrease in species plurality and interrelation between the two different ecosystems – the steady one on the reservoir site and the river on the other – is violently interrupted creating potential eliminations in the capacity and tolerance of the whole ecosystem (Jong, 2002).
2.2 River Ecosystems and its Impact of Dams
Rivers are central elements in many landscapes. They are important natural corridors for the flows of energy, matter and species, and are often key elements in the regulation and maintenance of landscape biodiversity (Nilsson &Jansson, 1995). The ecosystem of a particular river can be viewed as all the biotic and abiotic components of the environment linked to that river. It includes not only the aquatic habitats associated with water in the channel, but all the elements of the river catchment. Thus, a river ecosystem includes the headwaters, the channel from the headwaters to the sea, riparian areas, associated groundwater in the channel/banks and floodplains, wetlands, the estuary and any near shore environment that is dependent on
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freshwater inputs. Near-shore marine environments are often highly dependent on inputs of freshwater and associated nutrients and sediments from rivers. Coastal wetlands are ecologically and environmentally diverse because of the gradual and often fluctuating dynamic boundaries between salt, brackish and freshwaters. Salt water may penetrate considerable distances upstream, but boundary patterns vary with flow regimes and geo-morphological forms. These patterns influence not only vegetation, but also animal behavior, such as the degree to which marine species can range into the food-rich wetlands (Nilsson &Jansson, 1995).
River ecosystems are adapted to the natural hydrological regime and many components of those systems rely on floods for the exchange, not just of only water, but also energy, nutrients, sediments and organisms. The spatial and temporal variation in water depth and flow patterns as well as the frequency and duration of inundation, at different locations on a floodplain are responsible for a diverse array of habitats and hence ecological diversity, all of which are maintained by flooding. It is flooding and the consequent transfer of material that makes rivers and floodplains amongst the most fertile, productive and diverse ecosystems in the world.
Dams constitute obstacles for longitudinal exchanges along fluvial systems. The most obvious effect of storage reservoirs is the permanent destruction of terrestrial ecosystems through inundation. Upstream of dams, submerged terrestrial biotopes are completely destroyed. The most common downstream effect of large dams is that variability in water discharge over the year is reduced. Total discharge may be reduced in instances where evaporation rates are high and/or water is removed directly from the reservoir. Reduction of flood peaks reduces the frequency, extent and duration of floodplain inundation. Truncated sediment transport results in
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complex changes in degradation and aggregation below the dam. Reservoirs act as thermal regulators so that seasonal and short-term fluctuations in temperature, that are characteristic of many natural rivers, are regulated. The chemical composition of water released from reservoirs can be significantly different to that of inflows. Changes occur in pH and salinity as well as in the concentration of nutrients (e.g. phosphorous), carbon-dioxide, oxygen, hydrogen sulphide, iron, manganese and even heavy metals (e.g. mercury) (Nilsson &Jansson, 1995).
The changes caused by dams directly and indirectly influence a myriad of dynamic factors that affect habitat heterogeneity and successional trajectories and ultimately the ecological integrity of river ecosystems (Ward & Stanford, 1995).
2.2.1 Criticism about large dams
In recent years the worth of dams to human society has been questioned. Over the last two decades the value of natural ecosystem functions to human society and the environmental consequences of dams have become more widely understood. Opponents of dams argue that in many instances the environmental and social costs outweigh the economic benefits gained (by some) from dam construction (Ward & Stanford, 1995).
Dam proponents maintain that large dams are essential for the well-being of many millions of people and have played a key role in human development. They argue that many of the alternatives to dams are at present either uneconomic (e.g. desalination), impractical (e.g. towing ice-bergs from the Polar Regions) or more environmentally damaging (e.g. thermal and nuclear power stations). They also argue that many of the negative impacts of dams can be mitigated for
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and that with increasing world population there will be a need for increased dam construction in the future. The key issue is whether in the long-run dams will or will not provide a net benefit to humankind (Ward & Stanford, 1995).
2.2.2 Upstream impact of large dams
The construction of a dam results in post-impoundment phenomena that are specific to reservoirs and do not occur in natural lakes. When a reservoir fills it has a major impact on the ecosystems upstream of the dam. However, once a reservoir has formed and has reached a state of stability, its subsequent dynamic behavior is often very much the same as that of a natural lake. One difference is that lake level fluctuations may be much larger than are normal in a natural lake.
Dams also often have a bottom outlet, which allows both sediment flushing and water from deep below the surface to be released; both phenomena that happen only rarely (if ever) in natural lakes. Nevertheless older reservoirs can be considered as lakes and the challenges presented in managing them are often the same (Dinar, Seidl, Olem, Jorden, Duda, & Johnson, 1995). Within many reservoirs, considerable periods of dissolved oxygen exhaustion occur immediately after dam closure as a result of decomposition of newly submerged vegetation. Although a reduced, stable, trophic state eventually becomes established, the period of trophic upsurge and anoxia may persist for more than 20 years after reservoir filling (Pavia, 1988). Furthermore, first filling of reservoirs, particularly in the tropics, is often associated with an upsurge of nutrient release, as a result of the decay and mineralization of flooded organic matter.
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2.4 Importance of Mammals to Biodiversity
Mammals play key roles within the ecosystems in which they live, and are critical in maintaining the functions and services provided by ecosystems. They achieve this through their roles as grazers, predators, pollinators and seed dispersers. Mammals also provide numerous benefits to humans, both directly and indirectly; they are an important food source for many cultures, and are used in recreation and improving livelihoods around the world. Indirectly, mammals are very important in maintaining balanced ecosystems and the services they provide to mankind.
The ecological and economic consequences of losing large‐mammal populations vary depending on the location and the ecological role of the species lost. The loss of carnivores had induced trophic cascades: in the absence of top predators, herbivores can multiply and deplete the plants, which in turn drives down the density and the diversity of other species (Ripple & Beschta
2006). Losing large herbivores and their predators can have the opposite effect, releasing plants and producing compensatory increases in the populations of smaller herbivores (e.g. rodents:
Keesing, 2000) and their predators (e.g. snakes: McCauley, Keesing, Young, Allan, & Pringle,
2006). Such increases, while not necessarily detrimental themselves, can have unpleasant consequences. Many species depend on the activities of particular large mammal species. Certain trees produce large fruits and seeds apparently adapted for dispersal by large browsers
(Guimarães, Gentile, Alencar, Lopes, & Mello, 2008). Defecation by large mammals deposits these seeds and provides food for many dung beetles of varying degrees of specialization. In East
Africa, the disturbance caused by browsing elephants creates habitat for tree‐dwelling lizards
(Pringle, 2008), while the total loss of large herbivores dramatically altered the character of an
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ant‐plant symbiosis via a complex string of species interactions (Palmer, Allan, Meyer, &
Bernhardt, 2008).
Forests around the world are being diced into smaller and smaller fragments. Now it turns out the animals living in these tiny patches are more vulnerable than anyone knew. A case study in Thailand suggests that the native mammals can go extinct in just 25 years. That's worrying, because small fragments like this are becoming the norm all around the world. The study began when Thailand flooded a vast area of rainforest to build a hydroelectric dam in 1986.
Poking above the waters of the new ChiewLarn reservoir were 100 islands of pristine tropical rainforest. Laurence identified 16 islands, varying in size from 0.3 to 56.3 hectares, and studied how quickly the small mammals there became extinct.
Five years after the flooding, the nine fragments under 10 hectares in size had already lost almost all their small mammals. On average they had just two species left, whereas the larger islands had seven to 12 species. When researchers revisited the islands 20 years later, they found the larger ones had met the same fate. The only mammal left in any abundance was the
Malayan field rat, an invasive species that doesn't venture far into larger forests, but had evidently colonized the islands. The native species had declined so much that on many islands the team could only find a single individual.
2.5 Effects of Dams on Human Life
In spite of the fact that the dams are an important target for development; they are not easily acceptable for the people whose agricultural areas, houses and the environment they are living in go under water (Tahmiscioğlu, Anul, Ekmekçi & Durmuş, 2007). For example, when the Volta
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Lake was created in Ghana in 1969, although a much better settlement area was provided for 80
000 people in another location, these people have returned as 100 000 people and have built their own houses unplanned on the lake shore. Such an unsuccessful experience caused by the social- psychology can be very dangerous for the biosystems in the region and for the reservoir itself
(Tahmiscioğlu, et al., 2007). There are changes in the employment and production systems starting before the construction of the dam including expropriation of the land, employment of construction workers and the transport of construction material with the machines to the site.
Unqualified workers are employed from the site; however the technicians and experts come from other places. Generally settlement areas, social buildings, hospitals, schools etc. are built for the people coming from outside at the site. The more these facilities can be held open for public usage the more the dam becomes a kind of symbol for development. The new settlements improve by this way and result in second ecological needs and changes. For example, drinking water, domestic waste water, wastes water treatment etc. Moreover, the social life becomes active, trade increases, cultural activities rise. Important alterations are observed in the transportation system. The ways lying under water and their surrounding area are important from this point of view. The new roads that were constructed to prevent any break down in the transportation services result in additional expenses and additional environmental costs. At the same time dams decrease the pollution effect considerably in the downstream part by lowering the pollution load coming from the source, thanks to their big storing reservoirs. In addition, they decrease the pollution load again by containing water continuously in their beds during dry periods. Dams decrease the flood risk in the downstream, by their storing opportunity in their reservoir. Undoubtedly there are real and potential benefits obtained from these projects.
Industrial development has gained speed; irrigation channels and food production have improved
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as a result of the increase in electricity generation. Meanwhile, dams protect the people living downstream from floods. After comparing harms and benefits for a long period of time, a decision can be given about dams. May be the unwanted side effects of dams will be no longer in force because of the benefits in the future. But these big engineering structures should remind us that we are not able to change only a part of the ecosystem. Because whole chains are connected together in the ecosystem. Even only a link breaking out of the chain or a piece coming out of the cog will destroy the whole system. So, the environment subject should be examined in detail at the planning stage. Precautions should be taken beforehand to big hazards caused by the most little sensitive responses (Tahmiscioğlu, et al., 2007).
In addition to their very important social and environmental benefits, it is important to minimize the negative effects of dams on the environment regarding sustainable development. The mentioned effects and their solutions have taken into account in the environmental impact assessment concept. In summary, the environmental changes coming out of dams are in various amounts and in different importance degrees. It is difficult to consider the relations between these effects beforehand and determine which positive and negative effects will come up. This estimation should be made separately for each dam and reservoir. On the other hand, it is false to comprehend the effects totally negatively. The important point is who will do the assessments and from whose point of view. Will they be based on the fisherman, based on the industrialist or the farmer whose field will be under water? No matter who has taken the decision or whom the decision will take into centre, as long as whole environmental effects are explained totally according to their importance level (Tahmiscioğlu, et al., 2007).
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2.6 Effects of Dam Construction on Species
Dam construction offered preferable conditions of aquiculture development. It also changed many dams to the aquatic serve base. However, dam still submerged lots of ground and blocked the relationship of river being net-work. It affected the inhere survival and propagate eco- environment of wildlife. The first effect of a dam is to alter the pattern of disturbances that the plants and animals of a river have evolved. Many aquatic animals coordinate their reproductive cycles with annual flood seasons (Dynesius & Nilsson, 1994). Every flood is valuable in that it takes nutrients from the land and deposits them in the river, providing food for the stream‟s residents. Floods also provide shallow backwater areas on vegetated and shaded riversides; the young of many animals depend on these backwaters to protect them from large predators. For example, a fish on a certain river may only reproduce during April of every year so that its offspring will have abundant food and places to hide. If the flood never comes because a dam holds the river back, the offspring may be produced during a time when they cannot possibly survive. If the fish can wait until the next flood, which may be in July or October, its young will be born during the wrong time, and will have to contend with the absence of their normal food supply and temperatures for which they are not prepared.
The changes of the habitat‟s conditions affected the living rule, food chain, species movement, diffuse ranges and spawn of the hydrophilic. Parts of species decreased or disappeared as environment maladjustments. After the dam was constructed, intrinsic river systems were completed with allusions, beaches and watercourses and became a relative erected single watercourse. This reduced species of intrinsic animals and plants, and depressed the biodiversity.
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River level changes may cause some kickbacks to the water eco-environment followed by the modes of hydropower need changes, such as river level rapidly changed caused the erosion of lower reaches of water-courses. Alternately, exposure and submerged shallow may destroy the rest locations of shoal and disturb shoal spawn and so on. Besides, river temperature changes also altered the survival environment and lifecycle of the aquicolous species. Rivers tend to be homogenous in temperature. Reservoirs, on the other hand, are layered. They are warm on the top and cold at the bottom. If water is released downstream, it is usually released from the bottom of the dam, which means water in the river is now colder than it should be. Many macro- invertebrates depend on a regular cycle of temperatures throughout the year. When we change that, we compromise their survival. For instance, a certain stonefly may feel the cold temperatures and delay its metamorphosis. This may mean that at a certain life stage it will be living in deep winter rather than in autumn. Dams destroyed the habitat of parts of triphibian plants and made their biological resource changed. Dams also affected the exchange of species and altered the habitat of lower river aquicolous animals and plants (Wu, Mickley, Jacob, Rind,
& Streets, 2008).
Dams weakened the flood peak, adjusted the water temperature and reduced the diluted function of lower reaches of a river. It caused the increase of plankton quantity and distributing character and amount changes of invertebrate. Dams reduced the flood submerge and grass roots erosion.
It increases sediment of nutritional silver sand, which led large-scale water plant can be row and propagate. Owing to the head off much cobbles and graves, the invertebrates such as insect, mollusks and testacean lost their living environment.
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Dams shut off the migrate channels of some migratory fishes. As the released water has a low temperature by dam deep hole, the growth and propagation of fishes may be affected. Released rinsing also influenced the fish feed, which affected its output. When high dams overall and flood discharges, high speed current caused excessively saturation of the water. Moreover, it caused fish bleb disease. For instance, the Gezhou Dam on the Yangtze River, it has a flush flux of 41300-77500 m3/s, and the oxygen saturation: 112-127, nitrification saturation: 125-135%, lethal ratio of par: 32.24% (Li, Zhu, Xiao & Wang, 2010). The fish passage is concerned with dams. Many fishes must move upstream and downstream to complete their lifecycles. Dams are often built without fish ladders. When fish ladders are provided, they seldom work as needed. If enough adult fishes do manage to climb above a dam, there remains the issue of their young: how will they get back downstream? Predators kill many while wandering in the reservoir above the dam. Many are killed in their falling downward through the dam to the river below. They are not killed by the fall itself, but by the high levels of nitrogen gas at the base of the dam (Nilsson
& Jansson, 2005). In other words, like divers who go too deep, they get the “bends”. Many fishes cannot climb dam ladders or leap over low dams. Some of these fishes swim upstream every year to breed, then let the water carry them back down-stream. The eggs of pelagic spanners float downstream, in addition, which is why the adults must swim far up-river to breed.
Otherwise, the baby fish would soon end up out to sea.
The changes of grade, temperature, humidity, loftiness and groundwater would lead to the evolvement of organism community and parts of species were reduced or disappeared. As for the effects of triphibian plants and animals, it can be divided into two parts: one is permanent or direct effect, such as the reservoir region and the permanent engineering buildings causing a
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direct effect; the other is indirect effect including local climate, soil swamp and basification causing animal and plant species, structures and living environment to be changed.
Mammalian herbivores are known to have important effects on ecosystem processes in many biomes, including temperate forests. For example, ungulates can influence the nitrogen cycle by changing litter quality (and thus affect conditions for nitrogen mineralization), and by adding readily available nitrogen to upper levels of the soil through urine and feces, which can result in drastic changes in plant community composition (Hobbs, 1996). Not much is known about nutrient cycling in Patagonian forest ecosystems in general (Mazzarino, Bertiller, Sain, Satti, &
Coronato, 1998), much less about how it is affected by introduced herbivores. Deforestation by beaver in Tierra del Fuego leads to increased erosion and increased accumulation of organic material in water courses, which can in turn affect nutrient cycling, altering the biochemical composition of waters, sediments, soils, and adjacent riparian areas (Lizarralde, Deferrari,
Escobar & Alvarez, 1996). Decreased plant cover and trampling resulting from ungulate activity can significantly affect soil properties, including litter quality and mineralization processes, and can lead to soil erosion (De Pietri, 1992).
2.7 Inundation effect on Wildlife
Inundation of the reservoir will result in drowning of some terrestrial fauna unable to escape from flooded forest, grassland, and savannah woodland habitats. The reservoir will fill slowly which should avoid large scale direct loss, as most animals will be able to move to higher ground as the water level rises. Mortality due to drowning is likely to be most prevalent in ground- dwelling and feeding mammals, and certain primates, which mainly reside in the upper canopies
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of trees. The presence of the reservoir will cause a shift in the terrestrial wildlife species assemblage from riparian to lacustrine with some adverse and some beneficial effects.
Specifically, the reservoir will reduce habitats for wildlife species that require flowing water
(some insectivorous birds and bats) but increase foraging habitat for wildlife that prefer still or slow-moving waters such as waterbirds (Ministry of Energy, 2007). Beneficial effects will arise from the new habitats provided by presence of the reservoir, and an increase in the year-round availability of water for wildlife within the park. Inundation of the reservoir will eliminate existing dry-season hippopotamus pool habitats within the park, displacing the hippos that use these pools for resting. During the transition period when the reservoir is filling and shoreline vegetation communities are not yet established, hippopotamus will move from these traditional pools and feeding areas in search of suitable resting and foraging areas. They will be particularly vulnerable to hunting during this period. However, once the reservoir is full and vegetation communities are established along the shoreline, hippopotamus will benefit from the increased area of littoral habitat provided by the reservoir (Ministry of Energy, 2007).
2.7.1 Short Term Effects of Inundation on Wildlife
Inundation of the reservoir will result in drowning of some terrestrial fauna unable to escape from flooded forest, grassland, and savannah woodland habitats (Ministry of Energy, 2007). The reservoir will fill slowly which should avoid large scale direct loss, as most animals will be able to move to higher ground as the water level rises. Mortality due to drowning is likely to be most prevalent in grounddwelling and feeding mammals, such as the aardvark, tortoise and other small animals with limited mobility. Certain primates, such as black and white colobus monkeys, live in groups and spend over 50% of their time in tall trees (approximately 30m high) to avoid aerial
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and ground predation (Ministry of Energy, 2007). As these primates mainly reside in the upper canopies of trees, they are at risk of being stranded in trees by the rising water. The number of individuals affected is not expected to be high as they are highly mobile. The overall impact of inundation on species is therefore considered to be of moderatesignificance. Displacement of territorial and gregarious animals from the reservoir area as it starts to fill, for example ungulates such as kob and waterbuck, could cause short term disorganisation of the social structure of herds. This could alter reproductive behaviour, and cause aggression and increased stress, leading to injury, disease or mortality in some young, old or otherwise vulnerable individuals
(Ministry of Energy, 2007). The magnitude of the effect will be high initially, but will decrease over time as the animals re-orient to the new habitat conditions and herds stabilise, and therefore this impact is likely to be minor.
2.7.2 Long term Effects on Wildlife
The presence of the reservoir will cause a shift in the terrestrial wildlife species assemblage from riparian to lacustrine with some adverse and some beneficial effects. Specifically, the reservoir will reduce habitats for wildlife species that require flowing water (some insectivorous birds and bats) but increase foraging habitat for wildlife that prefer still or slow-moving waters such as waterbirds. Beneficial effects will arise from the new habitats provided by presence of the reservoir. Lake Kariba provides a case study of these responses to the shift from riverine to lacustrine habitat. Populations of crocodiles, aquatic birds, hippopotamus, and ungulates markedly increased in Lake Kariba following inundation and still persist in high numbers there today. The impact on species and species groups of conservation interest are discussed in the following sections. The Bui reservoir will significantly increase the year round availability
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ofwater for wildlife within the park. In the dry seasontoday, parts of the riverdry out and water scarcity becomes severe for wildlife that travels dailybetween the savannah and the river to drink such as the ungulates, savannahbuffalo, kob, defassa waterbuck, hartebeest and oribi. During this period ofthe year, animals are forced to seek portions of the river with water, whichresults in increased energy expenditure and exposure to predators. Thereservoir will provide a year round drinking water source for wildlife andhave a moderatebeneficial impact on all wildlife that use the reservoir as adrinking water source.The significance of habitat fragmentation caused by the
Bui Project for wildlifewill be moderate. Some wildlife species known to occur at Bui are capable ofpersisting in fragmented forests and research indicates that fragmented forestsmay play a key role in the preservation of many wildlife species in WestAfrica. The strategies implemented to manage the forest patches remainingafter construction will therefore play a significant role in determining theultimate impact of the project on forest-dependent wildlife.
2.7.3 Effects of Inundation on Hippopotamus
Due to the global conservation status of hippopotamus (IUCN vulnerable) and the fact that Bui
National Park contains the larger of only two hippopotamus populations in Ghana, concerns regarding possible effects of the Bui Project on this species have been raised by relevant authorities and interested groups. Inundation of the reservoir will eliminate existing dry-season hippopotamus pool habitats within the park, displacing the hippos that use these pools for resting
(Ministry of Energy, 2007). During the transition period when the reservoir is filling and shoreline vegetation communities are not yet established, hippopotamus will move from these traditional pools and feeding areas in search of suitable resting and foraging areas. They will be particularly vulnerable to hunting during this period. Once the reservoir is full and vegetation
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communities are established along the shoreline, hippopotamus will benefit from the increased area of littoral habitat provided by the reservoir (Ministry of Energy, 2007). Hippopotamus require two primary habitat elements for survival: water that is deep enough to submerge in, and nearby suitable forage. Preferred habitats include slow moving rivers or lakes (rapids or areas with high water currents are avoided) with firm substrates on which herds can stand or kneel partially submerged and calves can nurse without swimming. Common forage species include
Seteriaand Panicumgrasses, among other grass and herbaceous species. Individuals can feed at night on land up to 10 km from their daytime aquatic habitats, however the species prefers forage sites that are closer to the water for feeding (Ministry of Energy, 2007). The topography of the
Bui reservoir area means that the shoreline of the reservoir will slope gently and contain many finger-like extensions providing ample shallow water habitat for hippopotamus resting. Grass and herbaceous vegetation will grow around the lake shore, providing suitable fodder immediately next to the daytime aquatic habitat. In other reservoirs in Africa, most notably Lake
Kariba, hippopotamus populations have benefited from the presence of resting (aquatic) habitat and abundance of fodder along the reservoir shoreline. Overall, the ten-fold increase in the length of the littoral zone is likely to be of moderate beneficial impact for the Bui hippopotamus population over the medium- to long-term.
2.7.4 Effects of Inundation on Ungulates
Ungulates such as kob and buffalo are common in the Park and migrate seasonally throughout the Park in response to food and water availability. Food availability for these species is largely controlled by soil moisture, which will increase in the project area as a result of the elevated water table surrounding the reservoir. Although the reservoir will inundate over 20,000 ha of
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existing grassland habitat, improved water availability will increase the value of remaining grasslands as habitat for grazing mammals and provide a year-round source for drinking. On balance this is expected to provide minor benefit for ungulate populations in the project area.
2.7.5 Effects of Inundation on Primates
Primate species richness typically declines proportionately with habitat patch size. Studies conducted in eastern Kenya found a correlation between the basal area of food trees and the density of red colobus within forested habitat patches (Ministry of Energy, 2007). Frugivorous species are often the most susceptible to the effects of fragmentation (Ministry of Energy, 2007).
Studies have, however, also shown that many species of primates that typically occur in intact forests, including black and white colobus monkeys, can also use edge forests due to a combination of the ability to move between patches and dietary plasticity (Ministry of Energy,
2007). This suggests that primates in the project area should be able to move to nearby suitable habitats, provided these are not already at carrying capacity. Given the hunting pressure in the area, it is unlikely that primate habitats will be at or near carrying capacity and impacts on local populations are therefore expected to be minor.
2.8 Temporary Effects on Wildlife during Construction
Dam construction and inundation may result in the short term disturbance of terrestrial wildlife in the vicinity of construction sites, temporary access roads and worker camps.
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2.8.1 Disturbance of wildlife
A large number of construction workers will be housed in close proximity to the dam site during the construction phase. The exact location of the worker camp is expected to be near to the village of Bongase, approximately 4 km south of the dam site in what is now primarily wooded savannah. The construction camp could reach the size of a small village, and displace animals from the associated vegetative cover within the camp and from the immediate surrounding area.
Animals could migrate either north into the Park where habitat availability will become limited following inundation or south to unprotected areas where hunting pressure could increase. The extent of impact will depend on the size and location of the camp but is expected to be of moderate short term significance. Restoration of the site after construction should enable re- establishment of suitable habitats (Ministry of Energy, 2007).
2.8.2 Effects of noise, traffic and other human activity
The activity associated with camp construction, movement of people into the camp, and day-to- day activities once the camp is operational will further displace fauna from surrounding areas.
Construction activity will generate noise from people, vehicles, excavation equipment, concrete batch plants, crushers and blasting, affecting fauna sensitive to disturbance. This will include most primates and ungulates. In addition, without adequate management of on-site construction activities, there is a risk of accidental wildlife injury and mortality due to interaction with construction machinery, traffic and workers. The effects will be minor and localised and some of the temporarily displaced fauna are likely to return to the area when construction is complete.
Dust from construction activity could also affect natural vegetation and crops in the area around construction operations. The affected area is likely to be relatively small (up to a few hundred
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metres from dust generating activity) and with good construction site management the impact is predicted to be of minor significance (Ministry of Energy, 2007).
2.8.3 Increased hunting pressure during construction and inundation
During construction animals will also be vulnerable to heightened hunting pressure for a number of reasons:
The influx of construction workers will lead to increased hunting pressure in habitats
surrounding the construction camp;
The upgraded site access roads will improve accessibility to the Park, further
exacerbating hunting pressure;
There may be an increased threat from poachers taking advantage of the confusion
amongst animals fleeing from rising waters;
Loss of habitat in the impounded area could cause displaced animals to seek refuge in
unprotected areas outside of the park or in the Banda Nkwanta area of the northern region
of the Park where hunting pressure is thought to be high (Ministry of Energy, 2007).
Species most likely to suffer from increased hunting pressure within the park include grasscutter, antelope, buffalo, partridge and certain primates, as these species are reported to be most commonly hunted within the park and its immediate vicinity (Ministry of Energy, 2007).
Primates such as the green monkey and black and white colobus were identified during local discussions as the least prevalent large mammals in the park (Ministry of Energy, 2007) and will therefore be most at risk from increased hunting pressure. Hunters generally view the riverine forest to be the most species rich area and the inundation of approximately 12,380 ha of the most productive hunting area in the Park will intensify hunting pressure on wildlife in the remaining
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riverine forest habitats. The impact of increased hunting pressure during construction and inundation is considered to be of moderate-major significance, because without suitable mitigation and management measures, the likelihood of mammals of global and national conservation concern being affected, including hippopotamus, duikers, colobus, and mangabey, is high (Ministry of Energy, 2007).
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CHAPTER THREE
METHODOLOGY
3.1 The Bui hydropower dam
The Bui Hydropower dam is built in Ghana in the area of the Black Volta River (River) at the boarder of the Bole (Northern Region) and Wenchi (Brong-Ahafo Region) Districts in northwestern Ghana, 150km upstream of Lake Volta, as shown in Figure 3.1. The project started in 2007 and the first impound was recorded on 8 June of 2011. It was built under the recommendation of the Ghanaian government who considered its implementation critical to meet
Ghana‟s future energy demands. The dam has a total capacity of 400MW and a net average of
980 GWH/yr. Before the completion of the project, Ghana‟s main source of electricity (Apr.
1180MW) were the two hydroelectric projects located in southeastern Ghana, the Akosombo and the Kpong dams. The rest 550MW of the country‟s producing capacity was generated by thermal plants while a diesel plant at Tema was producing a supplementary amount of 30MW. The rest of the electricity demand was covered by importing electricity from the neighboring
Coted‟Ivoire. The specific location of the Bui Project at Bui Gorge is shown in greater detail in
Figure3.2. This site is particularly suitable for a hydroelectric project because of the relatively deep gorge where the Black Volta River flows through the Banda Hills.
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Figure 3.1: Location of the Bui Project
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Figure 3.2: Layout of the project
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The project is consisted of a main gravity roller compacted concrete (RCC) dam of a maximum height of 110m and a power house located in Bui Gorge and two smaller saddle dams in the neighboring Benda Hills. The dam will create a reservoir extending 40km upstream within
Ghanaian borders. The key components of the projects are:
Main dam;
Two saddle dams;
Reservoir;
Powerhouse and power intake;
Three transmission lines;
Switchyard;
Other facilities like site access roads and project control and maintenance facilities; and;
Temporary construction related project components
The reservoir will have at full supply level (FSL) a maximum surface area of 444km2 and will inundate almost 21% of Bui National Park as shown in figure 3.2. At FSL it will store 12.35 billion m3 of water with an average depth of 29m. The components of the dam are shown in
Figure 3.3.
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Figure 3.2: The main components of the Bui project
3.2 Research Design
Descriptive research design was used for this study. According to Burns and Grove (2003:201), descriptive research “is designed to provide a picture of a situation as it naturally happens”. It may be used to justify current practice and make judgment and also to develop theories.
Descriptive research design is a scientific method which involves observing and describing the behavior of a subject without influencing it in any way. It is used to obtain information concerning the current status of the phenomena to describe "what exists" with respect to variables or conditions in a situation. This was based on a cross-sectional data. Cross-sectional data or a cross section of a study population, in statistics and econometrics is a type of one- dimensional data set (Henry, Brady & Johnston, 2008). Cross-sectional data refers to data collected by observing many subjects (such as individuals, firms or countries/regions) at the same point of time, or without regard to differences in time (Henry, et al., 2008). Analysis of
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cross-sectional data usually consists of comparing the differences among the subjects (Henry, et al., 2008).
Both qualitative and quantitative methods were used for this study. The questionnaire was coded in order for it to fit into quantitative research methods. The quantitative approach of this research involved the deployment of self-administered survey for 398 respondents. Again, the qualitative data refers to subjective data associated with the respondents‟ opinions, positions, views and biases on the subject or issue under investigation.
Field Data was collected using Line Transect methodology, which is one of the best methods for estimating abundance. This method as described in Buckland, Anderson, Burnham and Laake
(1993); (see http://www.ruwpa.st-and.ac.uk/distance/) has the essential feature of an observer walking along a straight path, identifying and recording the individuals seen along the transect line. This is ideal as wildlife guard patrol teams can record these observations with ease within the Bui National Park. Some individuals to the side of the path being walked may escape detection by the observer, but the critical assumption is that all animals on the path are seen. Line transects can either be walked, driven, swum or flown however walking was the preferred option for the purpose of this study.
Advantages and disadvantages
o Line transects are extremely flexible, efficient and cheap as they require relatively little
time and equipment.
o Line transects are particularly suited to sampling large areas of relatively open
homogeneous habitat and species that are mobile, large or conspicuous.
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o The method is particularly useful for monitoring large mammals that occur at low
densities.
o Multiple species can be counted at the same time.
o In addition to walking, transects can be surveyed using ships, aircraft and cars. Roads and
tracks are often used as the path of the line transect.
o Line transects are also used to estimate the abundance of indices of mammal activity,
such as dung piles, burrows, footprints and other signs.
o There is a general problem of Non-random sampling of the study area if convenience
sampling is used instead of random sampling.
o Individuals must be located before they move or the detection function will be biased.
o Observers vary greatly in their ability to see animals, particularly if the habitat is less
open.
3.3 Data Sources
Data was collected from both primary and secondary sources through the use of personal interviews, direct observation, and self-administered Questionnaires with respondents. The secondary source of data was collected from the records of Bui National Park and Bui Power
Authority that includes among others, records of mammals and their health status. Secondary data sources are mainly used to supplement primary data to enable the researcher get more information concerning the topic. The information was collected through reading already written literature on post inundation effects of Bui Hydro Electric Dam on some selected mammals of the Bui National Park from text books, magazines, management reports, operations guidelines and other research work that had already been carried out.
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3.4 Population
The target population is the local community members and staff of Bui National Park in the
Banda-Ahenkro District in the Brong-Ahafo Region and Bole District in the Northern Region of
Ghana. The staff strength at Bui National Park was about 75 workers.
3.4.1 Banda-Ahenkro District
Banda District Assembly was carved out of the Tain District under the Legislative Instrument
L.I. 2092 and inaugurated on 28th June 2012. It is a small district with an approximate population of 45,000 and 33 communities. The district is drained by the Black Volta, Tombe andTain rivers. The aesthetic beauty of the district is enhanced by the NyuaKpoo Mountain and the SheliKpoo cave which are all potential tourist sites to be harnessed. It is essentially an agrarian District with majority of the inhabitants involved in fishing and crop farming.
The district is bordered to the West by Cote D‟ Ivoire, to the South by the Tain District
Assembly, to the North by the Northern Region and to the East by the Mo Traditional Council in the Kintampo South District.
3.4.2 Bole District
The Bole District used to be part of West Gonja District with Damongo as the Capital. The district was then created in 1988 as Bole, Sawla,Tuna and Kalba District, In 2004, under L.I
1786. Bole district was made as a separate district from Sawla/Tuna/Kalba to include
Maluwe, Tinga, Mandari, Banda Nkwanta, Taselima, Bamboi,etc. The District has Bole as its capital. Both Districts still remain part of the Gonja Kingdom established in the 17th Century by
NdewuraJakpa. It is also the cradle of Gonja culture with its traditional capital at Nyange which
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is located in the present day Sawla/Tuna/Kalba District. The Bole District assembly has been enjoined by Legislative Instrument (LI 1786), the Local Government Act (1993), ACT 462, the
1992 Constitution of Ghana, other Acts of Parliament to ensure the overall development of its
Area of jurisdiction.
The Bole district lies between Latitude 8 10° S and 09°and longitude 1 50E and 2 45 W. Bole
District is located at the extreme western part of the Northern Region of Ghana. The District is boarded to the North by Sawla/Tuna/Kalba District, to the West by the Republic of Ivory Coast to the East by West Gonja District and to the South by Wenchi and Kintampo Districts in the
Brong -Ahafo region. The District stretches from Bodi in the north to Bamboi in the south.
The Bole District covers an area of about 5,055 square km; out of the area of 72,865sq km of the
Northern region. It has an estimated population of about 60,237 (2010 PHC). The population growth rate is about 3.6% per annum. The population is sparse with a density of about 11 persons per square km. The District Capital Bole is the biggest town in the district. Other major towns include, Maluwe, Tinga, Mandari, Banda Nkwanta, Tasilma and Bamboi. For the percentage land take of District and the Northern Region in relation to Ghana (255,241.67sq km), they are 1.9% and 28.5% respectively. This means that the land take of the district is 6.9% of the total land mass of the Northern Region.
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3.5 Sampling Plan and Sample Size
The mathematical formula below given by Miller and Brewer (2003) was used to calculate thesample size since the population of the districts is known (that is 105,237 people in both districts). That is:
Where „N‟ is the sample frame or population, „n‟ is the sample size and „α‟ is the margin of error which in this case is (5%). The 95% confidence interval was chosen for this study because the study deals with human beings which accuracy of information is subject to biases unlike the physical sciences with high degree of certainty. By the formula, N=105,237 and α=
0.05.
Therefore;
Hence, the sample size is 398.
A cross-sectional data was collected among 398 households in both districts mentioned above and staff of Bui National Park. A multistage sampling procedure was employed. The first stage involved purposive sampling where the two districts were chosen due to their closeness to the
Bui dam and the Bui National Park. Since there are a lot of communities in the districts and they are mostly homogeneous, a cluster sampling was used to select 3 communities (Bongase,
Akanyakrom and Banda Ahenkro) from Banda-Ahenkro district and 4 communities (Banda
Nkwanta, Tinga, Maluwe and Ntereso) from Bole District because of their proximity to the dam.
This was done by writing the names of the communities on pieces of paper. The papers were
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then folded and shuffled. Seven (7) communities were then selected at random. Out of the seven
(7) communities selected, stratified random sampling procedure was used to select 50 people and
48 workers from Bui National Park making a total of 398 as the sample. Finally, in each of the communities, a purposive sampling procedure was again used to interview each of the 50 respondents as categorized above. The respondents were selected based on their experience on the field.
Biological data was collected using line transects walked by wildlife patrol teams across all the camps within the Bui National Park. All mammals observed were identified and recorded.
Observations of dead mammals as well as signs were also recorded using the line transects methodology as described in Sutherland, Pullin, Dolman and Knight (2006).
3.6 Data Collection Method
The homes and offices of the respondents were visited in order to collect the data. The research tool used was a semi-structured questionnaire that was designed by the researcher. The questionnaire consists of both open ended and close ended questions. Though, most of the household heads were unable to read or write, the questionnaire was used as a guide to assist the researcher to obtain clarification of responses and reliable information. In order to solicit the right information, the questions were read and explained in the local languages to the respondents for them to understand and respond appropriately.
The researcher also used observation method alongside interviews and questionnaires to gather information on the mammals because direct observation is said to have high face validity and is also referred to as external validity or ecological validity.
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3.7 Validity and Reliability
Pilot survey was conducted to validate the questionnaire. An instrument was developed and each question was scrutinized and modified until the researcher was satisfied that it was an accurate measure of the desired construct, and that there was adequate coverage of each area investigated.
Face validity was used for the likelihood that a question might be misunderstood or misinterpreted. There was a pre-testing of the survey to increase the likelihood of face validity.
To establish the face validity a questionnaire was sent to a sample of 10 respondents to evaluate their responses. The questionnaire was carefully measured in order to ensure that it is not prone to random error so as not to lack its reliability. In order to test reliability, a measure of internal consistency was used. An instrument which includes a series of questions was designed to examine the same construct. The questions were arbitrarily split into two groups which is the split-half reliability.
Table 3.1 Reliability statistics
Cronbach's Alpha Cronbach's Alpha Based on Standardized Items N of Items
.775 .747 39
The Cronbach‟s coefficient alpha as shown in Table 3.1 indicates that the questionnaire was reliable since the overall Cronbach‟s coefficient was greater than 0.7. This means that, the questionnaire is reasonably reliable as a measuring instrument. This is reiterated by Litwin
(1995) as values are considered good if r 0.70.
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3.7 Data Analysis
Data analysis involved compiling, selecting and entering data into computer files, inspecting it for errors and running tabulations and various statistical tests to derive proper findings for this study. The Statistical Product for Social Sciences (SPSS) and Microsoft Excel Software were used to analyze data obtained from the survey. Ecological data was analyzed using Estimates software package. The abundances and diversity data (Table 4.1) is an example of the data used to find averages of the number of mammals before and after the inundation periods.
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CHAPTER FOUR
RESULTS
4.1 The diversity and abundances of large mammals in the Bui National Park before, during and after the inundation
Table 4.1: Total Species Abundance
pre- pre- during COMMON inundati inundati inundati Post inundation SCIENTIFIC NAMES NAMES OF on on on (OCT 2014- OF MAMMALS MAMMALS (2009) (2010) (2011) SEP 2015) Synceruscaffer AFRICAN 16 12 9 3 BUFFALO Hippotragusequinus ROAN 73 91 22 65 ANTELOPE Kobusellipsiprymnus WATER BUCK 334 380 98 255 Kobuskob KOB 278 465 216 312 Tragelaphusscriptus BUSH BUCK 358 435 75 225 Phacochoerusafricanus COMMON 141 212 69 100
WARTHOG Cephalophusrufilatus RED-FLANKED 132 220 56 201
DUIKER Sylvicapragrimmia COMMON 27 19 1 14
DUIKER Ourebiaourebi ORIBI 183 170 20 128
Papioanubis OLIVE BABOON 414 451 201 218 Erythrocebuspatas PATAS MONKEY 491 525 239 324 Chlorocebussabaeus GREEN 442 478 221 314 MONKEY Hippopotamus amphibius HIPPOPOTAMUS 322 335 69 327
Lycaonpictus AFRICAN WILD DOG 31 5 3 7 Cercopithecuspetaurista LESSER SPOT- 310 305 131 203 NOSED
MONKEY Cercocebusatys SOOTY 8 13 22 16
MANGABEY Cercopithecusmona MONA MONKEY 6 27 52 12
Procolobusverus OLIVE COLOBUS 8 26 12 18
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From previous data (refer to Table 4.1) collected by the Bui National Park (BNP) the large mammals had remained the same in terms of species diversity. Eighteen (18) species of large mammals were documented during the experimental period (Oct.2014-Sept.2015) and this was the same with BNP records. The study confirmed that indeed 18 species of large mammals could be found with the BNP.
The large mammals assemblage was predominantly primates (Patas monkey, Green Monkey, olive Baboon, lesser spot-nosed monkey, sooty mongabey, mona monkey and the olive colobus) and ungulates (African buffalo, roan antelope, kob, bush buck, common duiker, red flanked duiker, water buck and the oribi).
Across the period of study, pre, during and post inundations the large mammal abundance had remained fairly the same with respect to the most abundant species. Within the primate complex the Patas monkey was the most abundant whereas the Kob was the most predominant Ungulate.
During the experimental period it was observed that the abundance of Hippopotamus surpassed that of the Patas monkey. This was shown by the month on month large mammals numbers recorded during patrols. The African Buffalo was the least observed throughout the experimental period. The Common Duiker and African wild dog also experienced very low abundances during the period.
The abundance records for 2011, during inundation showed marked reduction with reference to
2009 and 2010 pre inundation periods (Table 4.1). The 2014/15 abundance records showed increasing trends in abundance for most species with the Hippopotamus recording the highest abundances. As well, the primate (Patasmonkey, Green monkey, Olive Baboon, Spot-nosed monkey) were more than the ungulate (African buffalo, Water buck, Kob, Bush buck, Red-
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flanked duiker and Common duiker) before, during and after the inundation as shown in Table
4.1.
When the Ungulate abundances were compared between 2009 and 2014/2015 not a general pattern existed, but two different species (bush buck and kob) emerged the most abundant in the two different years.This was the only time bush buck had come up in the lead position against the kob. African Buffalo emerged the least abundant in both years. In 2010, there were very high abundances for most species with the exception of the African Buffalo and Common Duiker.
Again, 2011 marked the year in which inundation took place and the trend was clear, all ungulate species recorded low abundances during inundation in 2011 except the Kob. By 2014/2015 all ungulate species were recording an increase in abundances with the abundance of the Kob being the highest over the study period.
With respect to the primates the Sooty Mongabey, Mona and Olive Colobus monkeys recorded the lowest abundances over the study period whereas the Olive Baboon, Patas and green monkeys were the most abundant. In 2011, there was a startling decline in abundance for all species of primates. This was due to the inundation. However in post inundation, the Olive baboon, patas, green and lesser spot-nosed monkeys recorded significant gains in abundance.
This was suggestive of a recovery from the inundation process. The Mona and Olive Colobus monkeys however showed a minimal recovery.
The other species namely the Hippopotamus, African Wild dog and Common Warthog recorded a huge decrease in abundance in 2011 due to the inundation. It must be noted however that the
African Wild dog was least recorded pre (2010) inundation. Post inundation (2014/2015)
Hippopotamus recorded strong recovery almost to that in 2010, the highest abundance level. The common warthog was not left at the same level in the recovery process post inundation.
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Table 4.2 Diversity Indices
Index Value Richness R = 0D: 18.00
Shannon Entropy H' = ln(1D): 2.377 Shannon's equitability H'/Hmax 82.2%
Simpson Dominance =1/2D 11.7% unbiased (finite samples): 11.7%
The species richness (R) is the total number of different species present in the Bui National Park and does not take the proportion and distribution of each identified species within the Park. The large mammal diversity of 18 was a fair representation.
The Simpson Index (D) is a measurement that accounts for the richness and the percent of each species from a biodiversity sample within a local community, in this case the Bui National Park.
The index assumes that the proportion of individuals in an area indicates their importance to diversity. From the study for the year 2014/2015, Simpson index (D) of 11.7% indicated a low level of dominance suggesting that there was high species variation without one large mammal species dominating the community.
Bui National Park had a large mammal Shannon- wiener diversity index of 2.37 which suggested higher large mammal diversity.
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NO OF SPECIES
SAMPLES
Figure 3.2 True Diversity
Plotting true diversity showed that the curve was climbing at the 18 species mark hence with more sampling there would be larger mammal species identified within the Bui national Park.
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Figure 4.2: Mortality Records-2011
During inundation, mortality records indicated that Lesser Spot-nosed monkey experienced the highest mortality among the large mammals. Green monkey, Kob and Waterbuck also experienced high mortalities. This mortality record showed mostly for the months (June-
December 2011) immediately after full inundation had occurred. It is interesting to note that there had never been any records on mortalities in the past until June 2011, during inundation.
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Figure 4.3: Rescue Records-2011
During the inundation period several rescue operations were carried out. Spot-nosed monkeys were once again the most abundant of the rescued mammals followed by Sooty Mangabey and
Mona monkeys.The study confirmed that indeed the above mortalities (Figure 4.2) were as a result of the inundation.
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Questionnaires were administered and the total number of respondents was 398, which comprised 350 local community members and 48 staff of Bui National Park.
Table 4.3: Demographic Profile of the local communities
Demographics Number of Respondents Percentage of Respondents Gender Male 245 70.0 Female 105 30.0 Total 350 100.0 Age 21-30 years 145 41.4 31-40 years 124 35.4 41-50 years 69 19.7 51-60 years 12 3.4 Total 350 100.0 Occupation Farmer 245 70.0 Trader 105 30.0 Total 350 100.0 Level of Education No formal education 182 52.0 Primary 37 10.6 J.H.S 131 37.4 Total 350 100.0 Years of Habitation 5-9 yrs 3 .9 15-19yrs 34 9.7 20+ years 313 89.4 Total 350 100.0 Frequency of those who know where Bui Dam is Yes 304 86.9 No 46 13.1 Total 350 100.0 Those who have visited Bui National Park before and after Bui Dam was constructed Yes 350 100.0 Source: Field study, 2015
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4.2 Demographic Profile of the Respondents
Out of the 350 local communities studied, 105 representing 30% were females as shown in Table
4.3. This signifies that majority (70%) of the inhabitants studied were males. Moreover, most
(41.4%) of the inhabitants studied were between the ages of 21 and 30 years. Besides, majority
(52%) of the inhabitants studied had no formal education. Again, 37.4% of the inhabitants studied schooled up to Junior High School level and this formed the highest educational level of all the 350 local communitiesstudied. As well, majority (70%) of the inhabitants studied were farmers while the rest 30% were fishermen. Additionally, majority (89.4%) of the inhabitants studied had been in the area for more than 20 years. Even though 13.1% of the inhabitants do not know where Bui Hydro Electric Dam was, they had all paid a visit to Bui National Park.
Table 4.4: Demographic Profile of the Staff
Demographics Number of Respondents Percentage of Respondents Gender Male 40 83.3 Female 8 16.7 Total 48 100.0 Age 21-30 years 0 0.0 31-40 years 27 56.3 41-50 years 12 25.0 51-60 years 9 18.8 Total 48 100.0 Position Managerial level 2 4.2 Non-managerial level 46 95.8 Total 48 100.0 Level of Education No formal education 24 50.0 Primary 5 10.4 S.H.S/A/O-Level 8 16.7
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Diploma 9 18.8 Degree 1 2.1 Masters 1 2.1 Total 48 100.0 Length of Service with Bui National Park 5-9 yrs 9 18.8 10-14 yrs 19 39.6 15-19yrs 12 25.0 20+ years 8 16.7 Total 48 100.0 Frequency of those who know where Bui Dam is Yes 39 81.3 No 9 18.8 Total 48 100.0 Those who have visited Bui National Park before and after Bui Dam was constructed Yes 48 100.0 Source: Field study, 2015
Out of the 48 workers of Bui National Park studied, 40 representing 83.3% were males while
16.7% were females as shown in Table 4.4. Furthermore, majority (56.3%) of the staff studied were within the ages of 31 to 40 years. Interestingly, few (10.4%) of the staff studied had no formal education. Additionally, 18.8% of the staff had diploma while 1 person each had first degree and masters‟ degree. Again, only 2 staff members studied representing 4.2% were part of the management. Moreover, most (39.6%) of the staff studied had been in the institution within
10 to 14 years. Meanwhile, none of them had been in the institution for less than 5 years.
Though 18.8% of the staff studied did not know where Bui Hydro Electric Dam was, all of them had been working with Bui National Park and they knew what went on before and after the
Dam‟s construction.
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4.3 Perception of the State of Mammals in Bui National Park
Table 4.5: Weighted Rank Mean of the views of inhabitants on the state of mammals after
Bui Dam’s construction
Variables Mean Interpretation abundance or number of mammals 1.61 Reduced Mortality of mammals 4.00 Increased Diversity 1.61 Reduced Weight of mammals 3.94 Improved Water level 4.58 Highly Increased Water pollution 4.58 Highly Increased The prevalence of human-wildlife interaction around the park 3.56 Increased Overall wellbeing as compared to others in other water bodies 3.69 Improved Note: Mean of: 1=very poor or highly reduced, 2= poor or reduced, 3=the same or normal, 4= improved or increased, 5=very improved or highly increased SOURCE: Field study 2015
According to the local communities studied as represented in Table 4.5, the abundance of the mammals had reduced (1.61) as compared to the pre inundation periods. They had also indicated that, mortality had increased (3.89) because of the inundation. However, the diversitythey said had reduced (2.75). Moreover, the water pollution (4.47) and water level (3.89) had both increased. Despite the distraction as a result of the inundation, the inhabitants stated that the weight of the mammals had improved (3.94). Furthermore, prevalence of human-wildlife interaction around the park they said had also increased (3.56). In all, the inhabitants had rated the general wellbeing of the mammals as better than mammals in other water bodies around.
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Table 4.6: Weighted Rank Mean of the views of staff on the state of mammals after the inundation
Variables Mean Interpretation Abundance or number of mammals 1.61 Reduced Mortality of mammals 4.00 Increased Diversity 3.04 Remained the same Weight of mammals 1.61 Reduced Water level 4.58 Highly increased Water pollution 4.58 Highly increased The prevalence of human-wildlife interaction around the park 4.96 Highly increased Overall wellbeing as compared to others in other water bodies 1.92 Poor
Note: Mean of: 1=very poor or highly reduced, 2= poor or reduced, 3=the same or normal, 4= improved or increased, 5=very improved or highly increased SOURCE: Field study 2015
According to the staff and management studied as represented in Table 4.6, the abundance of the mammals had reduced (1.61) as compared to the pre-inundation periods. As for the mortality, they said it had increased (4.00), but the diversity they maintained that it had not changed (3.04).
The staff and management stated that the weight of the mammals had reduced tremendously
(1.61). Moreover, the water level (4.58) had highly increased as well as the water pollution
(4.58). Furthermore, prevalence of human-wildlife interaction around the park had highly increased (4.96). In all, the staff and management had rated the wellbeing of the mammals as poor as compared to other mammals in other water bodies around.
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4.4 Further Analysis
The state of mammals was further tested using both the primary and secondary data collected from the park. October to December data for both 2010 and 2014 were compared using the paired observation analysis. The following are the detailed analysis:
Table 4:7 Paired T-Test and Confidence Interval for abundances of Mammals before and after Bui Dam inundation
Paired T-Test and CI: Before, After
Paired T for Before - After
N Mean StDev SE Mean Before 18 65.4 91.5 21.0 After 18 123.8 149.8 34.4 Difference 18 -58.5 102.4 23.5
95% lower bound for mean difference: -99.2 T-Test of mean difference = 0 (vs> 0): T-Value = -2.49 P-Value = 0.989
95% CI for mean difference: (-107.9, -9.1) T-Test of mean difference = 0 (vs not = 0): T-Value = -2.49 P-Value = 0.023
95% upper bound for mean difference: -17.7 T-Test of mean difference = 0 (vs< 0): T-Value = -2.49 P-Value = 0.011 Source: Field study 2015
According to the study as indicated in Table 4.7, there was a significant difference between the pre, during and post-inundations of the large mammals‟ abundance in the Bui National Park.
This was because, the p-value was 0.023 which was less than 0.05 (the significance level).
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CHAPTER FIVE
DISCUSSION
5.1 Discussion of the Study
It is known that freshwater is an essential natural resource on which all living things depend.
However, the construction of the Bui Hydro-Electric Dam at Bui gorge inundated 21% of the core zone of the Bui National Park. The flooding upstream of the dam had resulted in the permanent destruction of terrestrial ecosystems. This loss of habitat, led to displacement of wildlife within this zone. The position of this research was that, not enough scientific consideration was given to the environmental repercussion the dam would cause on the Bui
National Park with regard to the loss of its pristine biodiversity. There was therefore the need to assess the effect this would have on the large mammals in Bui National Park as a direct consequence of the dam and its attendant inundation of the Bui National Park. The main objective was to assess the post inundation effects of Bui Hydro Electric Dam on the large mammals in the Bui National Park. The specific objectives were to: Find out the perception of the people in the catchment area about the large mammals in the Bui National Park before, during and after inundation, identify the different species of large mammals in the Park before, during and after inundation, determine the abundances of the various species of large mammals before, during and after inundation, determine the mortality of large mammals in the Park before, during and after inundation and finally compare the current state of large mammals and respective abundances to during and pre inundations. This was based on two sources of data, primary and secondary. Descriptive research design involving qualitative, quantitative and observational methods was used for the study.
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According to the (Ministry of Energy, 2007), during construction animals would be vulnerable to heightened hunting pressure for a number of reasons:
The influx of construction workers will lead to increased hunting pressure in habitats
surrounding the construction camp;
The upgraded site access roads would improve accessibility to the Park, further
exacerbating hunting pressure;
There might be an increased threat from poachers taking advantage of the confusion
amongst animals fleeing from rising waters;
Loss of habitat in the impounded area could cause displaced animals to seek refuge in
unprotected areas outside of the park or in the Banda Nkwanta area of the northern region
of the Park where hunting pressure was thought to be high (Ministry of Energy, 2007).
Species most likely to suffer from increased hunting pressure within the park include grass cutter, antelope, buffalo, partridge and certain primates, as these species were reported to be most commonly hunted within the park and its immediate vicinity (Ministry of Energy, 2007).
Primates such as theolive colobus were identified during local discussions as the least prevalent large mammals in the park (Ministry of Energy, 2007) and will therefore be most at risk from increased hunting pressure. Hunting area in the Park will intensify hunting pressure on wildlife in the remaining riverine forest habitats. The impact of increased hunting pressure during construction and inundation was considered to be of moderate-major significance, because without suitable mitigation and management measures, there was the likelihood of populations of mammals including hippos, duikers, colobus and mangabeys of global and national conservation concern being decimated, was high (Ministry of Energy, 2007).
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Interestingly,with these predictions in mind, the risk of animals being exposed to hunting pressure was brought under control. The Wildlife Division of forestry commission and the Bui
Power Authority (BPA) undertook community education and public awareness creation during the construction and inundation. The patrol operations by the wildlife guards in the Bui National
Park were also intensified to ensure that the integrity of the park and wildlife resources were safeguarded. Patrols were conducted to arrest poachers and other trespassers and also to deter poachers from entering the park. Notwithstanding the foresaid, some mortality did occur with the primates and ungulates (Fig. 4.2). But it was mainly by inundation particularly with the primates which was in line with the prediction that inundation of the reservoir will result in drowning of some terrestrial fauna unable to escape from flooded forest, grassland and savannah woodland habitats (Ministry of Energy, 2007). The reservoir will fill slowly which should avoid large scale direct loss, as most animals will be able to move to higher ground as the water level rose.
Mortality due to drowning was likely to be most prevalent in ground dwelling and feeding mammals, such as the aardvark, tortoise and other small animals with limited mobility. Certain primates, such as olive colobus, green, lesser pot-nosed, mona and sooty mangabey monkeys, live in groups and spend over 50% of their time in tall trees (approximately 30m high) to avoid aerial and ground predation(Ministry of Energy, 2007). As these primates mainly reside in the upper canopies of trees, they were at risk of being stranded in trees by the rising water. The number of individuals affected was not expected to be high as they were highly mobile. The overall impact of inundation on species was therefore considered to be of moderate significance.
Indeed,the overall impact of inundation on species was actually considered to be of moderate significance. That was because a rescue operation was carried out immediately the dam began to fill up by the Wildlife Division of Forestry Commission supported by the Bui Power Authority to
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rescue and relocate some of the distressed wildlife species that were trapped by the inundation process either in trees or on islands. The visibly stranded and distressed arboreal animals especially the primates were rescued, by literally driving them into the water where they were rescued easily as they were poor swimmers. Those trapped on islands were driven from one island to the nearest island by swimming in water until they were driven to a safe and natural habitat. At the end of the operation, a total number of five hundred and nine (509) large mammals were rescued as shown in Figure 4.3.
There was no change in species diversity between pre, during and post inundations, as the diversity of 18 species remained the same. The unaffected state in the species diversity was not unconnected with the abundant water supply all year round in the Park.
The inundation resulted in an immediate catastrophic decline in large mammals‟ abundance within the Bui National Park. All the 18 species experienced declines in their abundance in 2011 the year of inundation. This might be due to the construction works and its attendant human disturbance that might have driven the large mammals away as foretold bythe (Ministry of
Energy, 2007).The activity associated with camp construction, movement of people into the camp, and day-to-day activities once the camp was operational would displace fauna from surrounding areas. Construction activity will generate noise from people, vehicles, excavation equipment, concrete batch plants, crushers and blasting, affecting fauna sensitive to disturbance.
This would include most primates and ungulates. Additionally, without adequate management of on-site construction activities, there was a risk of accidental wildlife injury and mortality due to interaction with construction machinery, traffic and workers. The effects would be minor and
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localised and some of the temporarily displaced fauna were likely to return to the area when construction was complete (Ministry of Energy, 2007).
Furthermore, a large number of construction workers will be housed in close proximity to the dam site during the construction phase. The exact location of the worker camp was expected to be near to the village of Bongase, approximately 4km south of the dam site in what was now primarily wooded savannah. The construction of the camp could reach the size of a small village, and displace animals from the associated vegetative cover within the camp and from the immediate surrounding area. Therefore animals could move either northward into the Park where habitat availability would become limited following inundation or south to unprotected areas where hunting pressure could increase. The extent of impact would depend on the size and location of the camp but expected to be of moderate short term significance. Restoration of the site after construction should enable re-establishment of suitable habitats (Ministry of Energy,
2007).
The inundation itself which had led to a major habitat loss,might have also forced the large mammals to relocate to other suitable habitats. According to the(Ministry of Energy, 2007) again, displacement of territorial and gregarious animals for example ungulates such as kob and waterbuck from the reservoir area as it starts to fill, could cause short term disorganization of the social structure of herds. This could alter reproductive behavior and cause aggression and increased stress, leading to injury, disease or mortality in some young, old or otherwise vulnerable individuals (Ministry of Energy, 2007). The magnitude of the effect will be high initially, but will decrease over time as the animals re-orient to the new habitat conditions and herds stabilized, and therefore this impact was likely to be minor (Ministry of Energy, 2007).
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This was expected and predicted in the ESIA. The management procedures applied by the construction company to impound in a gradual manner allowed some species to escape being inundated.
The study however documents significant recovery of large mammals‟ abundances notably the hippopotamus which had recovered to almost that of the 2010 (highest) abundance levels pre inundation. This trend was remarkable as it was predicted that there will be a loss of habitat resulting in the predicted movement of Hippos to other areas. Inundation of the reservoir will eliminate existing dry-season hippopotamus pool habitats within the park, displacing the hippos that use these pools for resting (Ministry of Energy, 2007). During the transition period when the reservoir was filling and shoreline vegetation communities were not yet established, hippopotamus would move from these traditional pools and feeding areas in search of suitable resting and foraging areas. They would be particularly vulnerable to hunting during this period.
Once the reservoir was full and vegetation communities were established along the shoreline, hippopotamus would benefit from the increased area of littoral habitat provided by the reservoir
(Ministry of Energy, 2007). Hippopotamus required two primary habitat elements for survival: water that was deep enough to submerge in, and nearby suitable forage. Preferred habitats include slow moving rivers or lakes (rapids or areas with high water currents were avoided) with firm substrates on which herds could stand or kneel partially submerged and calves could nurse without swimming. Common forage species include Seteriaand Panicumgrasses, among other grass and herbaceous species. Individuals could feed at night on land up to 10 km from their daytime aquatic habitats, however the species preferred forage sites that were closer to the water for feeding (Ministry of Energy, 2007). The study showed that though there was a reduction in
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abundance during the inundation, the Hippopotamus had returned thus supporting the claims made in the EIA.
Though true for the Hippopotamus the study highlighted the very low recovery of some primates namely the Olive Colobus Monkey, the Sooty Mangabey monkey and the Mona Monkey whose abundances had not shown any sign of recovery. These Primates were identified during local discussions as the least prevalent large mammals in the park (Ministry of Energy, 2007) and will therefore be most at risk from increased hunting pressure. Primate species richness typically declines proportionately with habitat patch size.
The ungulates had shown good recovery as well except the buffalo and the Common Duiker.
These findings were contrary to the findings of Jong (2002). According to Jong (2002), ungulates such as buffalo and kob that migrate seasonally in order to meet food and water availability are likely to benefit from inundation since there was likely to be permanent water supply all year round. This would affect the usual migration patterns and most likely would lead to population increases. Even if inundation would cover a huge area of grassland habitats the increased water availability would increase the value of remaining grasslands as habitat for grazing mammals and provide a year-round source for drinking. Primate species richness typically declines proportionately with habitat patch size. There were studies though indicating that primates of the project might be able to move to nearby habitats as these were not already at carrying capacity
(Jong, 2002).
However, the recovery state of most mammalian species was in line with the findings of Jong
(2002). According to Jong (2002) again, the new situation that would be formed after the
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completion of the project and the inundation of the reservoir would provide a totally steady situation for the area in contrast with the constant energy flow that existed beforehand. This stability would give space to species to adapt to the new situation and would bring new inhabitants that may cause instability to the system, as there might be a newborn competition among the new and the old ones. On the other hand the lake fluctuation and the increased shorelines would create new room for species that were tolerant to this constant change and could act as stress-tolarators for the whole ecosystem. Although the extreme barriers were set, the dam itself to the upstream and downstream parts of the system provoked the decrease in species plurality and interrelation between the two different ecosystems – the steady one on the reservoir site and the river on the other – is violently interrupted creating potential eliminations in the capacity and tolerance of the whole ecosystem (Jong, 2002)
It was worth mentioning that the experimental results too revealed a decline in animals‟ numbers from April-September. This might be due to the tall nature of the grasses at the period as the mammals took cover thus making their sighting difficult. This observation was in conformity with the Bui National Park records pre inundation.
Questionnaires were administered and the total number of respondents was 398 which comprised
350 local community members and 48 staff of Bui National Park. The analysis and interpretation revolved around the perception of staff of Bui National Park and the local communities about the state of mammals at the Bui National Park after the inundation of Bui Hydro Electric Dam.
According toboth staff and local communities, the abundances of the mammals had reduced
(1.61) as compared to the pre inundation periods (Tables 4.8 & 4.9). They also both accepted
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that, mortality had increased (4.00).However, as for the species diversityaccording to the staff,had remained the same (3.04), which contradicted the views of the communities who feltthat the diversity had reduced (1.61). The staff and communities also shared divergent views on the state of mammalsinterms of their weights. While the staff opined that the weights of the mammals had reduced (1.61) due to the stress they experienced during the floods which was more evident during the rescue exercise, the local communities believed that the weights of the mammals had rather improved (3.94). Furthermore, there were no contrary views when it came to the water leveland pollution. Both staff and local communities were of the interpretation that the water level had increased tremendously (4.58) as well as the water pollution (4.58).
Within many reservoirs, considerable periods of dissolved oxygen exhaustion occur immediately after dam closure as a result of decomposition of newly submerged vegetation. Although a reduced, stable, trophic state would eventually become established, the period of trophic upsurge and anoxia might persist for more than 20 years after reservoir filling (Pavia, 1988).
Furthermore, first filling of reservoirs, particularly in the tropics, is often associated with an upsurge of nutrient release, as a result of the decay and mineralization of flooded organic matter.
Still, prevalence of human-wildlife interaction around the park brought dissimilar views between staff and the local communities. Whereas the staff were of the judgment that it had highly increased (4.96), the local communities were of the understanding that it had increased (3.56) but not highly. Even though human-wildlife interaction was very high according to the staff, the animals were not so much at risk of being poached. Besides the positive efforts by the Wildlife
Division of Forestry Commission and the Bui Power Authority mentioned above on the public education, Patrol staff werestationed around the Park 24hours to prevent strayed wild animals off-reserve from being decimated.
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Likewise, the staff and management rated the wellbeing of the mammals as poor (1.92) as compared to other mammals in other water bodies around. The local communities on the other hand, were of theassessment that there was an improvement (3.69) in their general wellbeing.
Though, we could see some disparities in the views of the staff and local communities, key attention should be paid on that of the staff since they were there and knew what went on every day.
Further analyses using Paired T-Test and Confidence Interval for abundances of Mammals before and after Bui Dam inundationin Table 4:7 indicated that there was a significant difference between the pre, during and post-inundations of the large mammals‟ abundance in the Bui
National Park. This was because, the p-value which was 0.023 was less than 0.05 (the significance level). That was an indication, the inundation had significantly affected the mammals of the Bui National Park.
Besides, there had never been any mass or individual records on animals‟ mortalityas shown in
Figure 4.2 in the Bui National Park before full inundation in June, 2011. Furthermore, animals such as hippopotamus, monkeys (green monkeys), crocodiles thatwandered off downstream off- reserve after inundation could not return to the park after the full inundation. These animals arehighly endangered as they are currently living in unprotected areas off-reserve.
68
5.2 CONCLUSIONS
Based on the findings of the study, the following conclusions were made:
i. there is a significant variation of the perception of the people in the catchment area about
the large mammals in the park pre, during and post inundation.
ii. There is a significant difference among the pre, during and post inundations abundances
of the large mammals in Bui National Park.
iii. There is a significant difference among the pre, during and post inundations mortality of
the large mammals in Bui National Park.
iv. There is no significant difference among the pre, during and post inundations diversity of
the large mammals in Bui National Park.
v. There is a significant difference among the pre, during and post-inundations water level
in Bui National Park.
vi. There is a significant difference among the pre, during and post inundations water
pollution in Bui National Park.
vii. There is a significant difference among the pre, during and post inundations prevalence of
human-wildlife interaction around the Bui National Park. viii. There is a significant weight difference among the pre, during and post inundations of the
large mammals in Bui National Park.
ix. There is a significant difference among the pre, during and post-inundations overall wellbeing
of the large mammals in Bui National Park as compared to other water bodies.
69
5.3 Recommendations
It is recommended that monitoring schedule should be developed to monitor the mega mammals to provide needed information for their management. The Bui National Park should be expanded to accommodate and ease mobility of all these mammals. This will help increase the abundance and composition of the mammals.
70
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APPENDIX A
The diversity and abundances of the large mammals in Bui National Park pre (2009) inundation ANIMALS SCIENTIFIC NAME JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC TOTAL OBSERVED AFRICAN BUFFALO Synceruscaffer 11 0 0 0 0 5 0 0 0 0 0 0 16 ROAN ANTELOPE Hippotragusequinus 12 16 8 4 2 0 2 0 0 0 0 29 73 WATER BUCK Kobusellipsiprymnus 36 72 98 14 34 0 7 0 0 7 0 66 334 KOB Kobuskob 21 18 14 63 43 10 15 0 0 36 0 58 278 BUSH BUCK Tragelaphusscriptus 32 45 57 33 60 45 3 0 0 10 2 71 358 COMMON Phacochoerusafricanus 13 27 52 21 2 0 0 0 0 0 0 26 141
WARTHOG RED-FLANKED Cephalophusrufilatus 14 47 19 27 2 0 2 0 0 3 0 18 132
DUIKER
COMMON DUIKER Sylvicapragrimmia 6 2 0 9 0 0 0 0 0 0 0 10 27 ORIBI Ourebiaourebi 15 55 19 20 3 0 9 0 0 1 0 61 183
OLIVE BABOON PapioAnubis 25 36 40 58 19 44 51 0 0 43 0 98 414 PATAS MONKEY Erythrocebuspatas 94 34 99 49 45 32 36 6 3 39 12 42 491 GREEN MONKEY Chlorocebussabaeus 42 57 19 67 48 57 5 0 0 31 64 52 442 HIPPOPOTAMUS Hippopotamus amphibius 18 29 23 45 56 45 34 5 9 36 2 20 322
AFRICAN WILD DOG Lycaonpictus 5 15 8 0 0 0 0 0 0 0 0 3 31
LESSER SPOT- Cercopithecuspetaurista 62 7 30 77 55 0 0 0 0 0 79 0 310
NOSED MONKEY
SOOTY MANGABEY Cercocebusatys 1 0 0 0 2 0 0 0 0 0 0 5 8 MONA MONKEY Cercopithecusmona 1 0 1 0 0 0 0 0 0 3 0 1 6
OLIVE COLOBUS Procolobusverus 1 0 4 0 0 0 0 0 0 0 0 3 8 Table 4.1
83
Table 4.2 The diversity and abundances of the large mammals in Bui National Park pre (2010) inundation ANIMALS SCIENTIFIC NAME JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC TOTAL OBSERVED AFRICAN BUFFALO Synceruscaffer 2 0 0 4 0 0 0 0 0 0 4 2 12 ROAN ANTELOPE Hippotragusequinus 12 15 9 14 10 4 0 2 0 17 5 3 91 WATER BUCK Kobusellipsiprymnus 88 91 70 24 34 19 12 0 0 9 11 22 380 KOB Kobuskob 91 68 48 87 37 18 0 0 0 15 71 30 465 BUSH BUCK Tragelaphusscriptus 60 82 73 69 0 0 0 0 4 8 69 70 435 COMMON Phacochoerusafricanus 55 67 6 22 0 0 0 0 0 0 10 52 212
WARTHOG RED-FLANKED Cephalophusrufilatus 44 51 23 19 16 16 11 5 2 6 0 27 220
DUIKER
COMMON DUIKER Sylvicapragrimmia 3 7 0 1 0 0 1 0 0 7 0 0 19 ORIBI Ourebiaourebi 33 41 26 20 18 5 9 7 0 4 0 7 170
OLIVE BABOON Papioanubis 34 89 32 77 30 0 2 0 0 54 42 91 451 PATAS MONKEY Erythrocebuspatas 45 67 56 64 44 42 22 13 21 34 51 66 525 GREEN MONKEY Chlorocebussabaeus 87 72 36 52 9 17 0 14 16 49 62 64 478 HIPPOPOTAMUS Hippopotamausmphibius 15 21 49 27 22 45 15 36 23 28 25 29 335 AFRICAN WILD Lycaonpictus 2 0 1 0 0 0 0 0 0 0 0 2 5
DOG LESSER SPOT- Cercopithecuspetaurista 54 67 56 24 17 0 0 7 8 0 0 72 305
NOSED MONKEY
SOOTY MANGABEY Cercocebusatys 5 0 3 3 0 0 0 0 0 0 0 2 13 MONA MONKEY Cercopithecusmona 12 9 0 2 0 0 0 0 0 0 0 4 27
OLIVE COLOBUS Procolobusverus 11 15 0 0 0 0 0 0 0 0 0 0 26
84
ANIMALS SCIENTIFIC NAME JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC TOTAL OBSERVED AFRICAN Synceruscaffer 9 0 0 0 0 0 0 0 0 0 0 0 9 BUFFALO ROAN ANTELOPE Hippotragusequinus 6 4 0 12 0 0 0 0 0 0 0 0 22 WATER BUCK Kobusellipsiprymnus 18 24 17 35 2 0 0 0 0 0 0 2 98 KOB Kobuskob 8 69 70 65 2 2 0 0 0 0 0 0 216 BUSH BUCK Tragelaphusscriptus 4 17 14 28 5 7 0 0 0 0 0 0 75 COMMON Phacochoerusafricanus 11 20 9 25 2 2 0 0 0 0 0 0 69
WARTHOG RED-FLANKED Cephalophusrufilatus 21 11 10 11 3 0 0 0 0 0 0 0 56
DUIKER
COMMON DUIKER Sylvicapragrimmia 0 0 1 0 0 0 0 0 0 0 0 0 1 ORIBI Ourebiaourebi 4 3 10 2 0 1 0 0 0 0 0 0 20
OLIVE BABOON PapioAnubis 59 31 26 71 14 0 0 0 0 0 0 0 201 PATAS MONKEY Erythrocebuspatas 35 41 66 78 0 19 0 0 0 0 0 0 239 GREEN MONKEY Chlorocebussabaeus 44 51 77 49 0 0 0 0 0 0 0 0 221 HIPPOPOTAMUS Hippopotamausamphibius 21 25 8 5 10 0 0 0 0 0 0 0 69 AFRICAN WILD Lycaonpictus 0 3 0 0 0 0 0 0 0 0 0 0 3
DOG LESSER SPOT- Cercopithecuspetaurista 25 35 19 38 12 2 0 0 0 0 0 0 131
NOSED MONKEY SOOTY Cercocebusatys 6 0 8 6 2 0 0 0 0 0 0 0 22
MANGABEY MONA MONKEY Cercopithecusmona 13 12 4 8 5 10 0 0 0 0 0 0 52
OLIVE COLOBUS Procolobusverus 0 12 0 0 0 0 0 0 0 0 0 0 12
85
Table 4.3 The diversity and abundances of the large mammals at Bui National Park during (2011) inundation
The diversity and abundances of the large mammals in the Bui National Park Post (2014/2015) inundation ANIMALS SCIENTIFIC Oct- Nov-14 Dec- OBSERVE NAME 14 14 Feb- Apr- Jun- Jul- Aug- Sep- D Jan-15 15 Mar-15 15 May-15 15 15 15 15 TOTAL AFRICAN Synceruscaffer 0 0 0 1 2 0 0 0 0 0 0 0 3 BUFFALO ROAN Hippotragusequin 6 5 19 18 12 1 4 0 0 0 0 0 65 ANTELOPE us WATER Kobusellipsiprymnu 34 21 31 42 33 36 54 3 1 0 0 0 255 BUCK s KOB Kobuskob 53 0 54 66 51 17 0 71 0 0 0 0 312 BUSH Tragelaphusscriptu 45 23 32 41 37 23 4 2 12 2 1 3 225 BUCK s COMMON Phacochoerusafri 9 2 8 13 11 20 26 3 0 0 0 8 100
WARTHOG canus RED- Cephalophusrufilat 52 41 0 0 56 44 0 4 0 0 4 0 201 FLANKED us
DUIKER COMMON Sylvicapragrimmi 2 0 4 4 0 0 2 2 0 0 0 0 14
DUIKER a ORIBI Ourebiaourebi 1 24 36 19 20 19 3 2 0 2 2 0 128 OLIVE PapioAnubis 9 6 23 81 7 4 34 54 0 0 0 0 218
BABOON PATAS Erythrocebuspatas 78 31 21 67 0 68 59 0 0 0 0 0 324 MONKEY GREEN Chlorocebussaba 0 99 12 28 72 64 20 3 0 0 16 0 314 MONKEY eus HIPPOPOT Hippopotamausam 17 26 91 29 31 10 28 19 39 22 0 15 327 AMUS phibius
86
AFRICAN Lycaonpictus 0 0 0 1 2 4 0 0 0 0 0 0 7
WILD DOG LESSER Cercopithecuspeta 5 45 7 2 79 11 31 23 0 0 0 0 203 SPOT- urista NOSED
MONKEY SOOTY Cercocebusatys 1 0 2 2 5 6 0 0 0 0 0 0 16 MANGABE
Y MONA Cercopithecusmo 0 1 5 4 0 0 0 0 0 0 2 0 12 MONKEY na OLIVE Procolobusverus 0 2 2 4 0 10 0 0 0 0 0 0 18
COLOBUS
Table 4.4
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Research Questionnaire for inhabitants of Bui National Park
Preamble: I am a postgraduate student of Kwame Nkrumah University of Science and Technology. I am conducting a research to assess the post inundation effects of Bui Hydro Electric Dam on the large mammals of the Bui National Park. This research is in partial fulfillment of the requirements for the award of Masters of Science in Environmental Science. You have been selected to assist the study by providing candid answers to the following questions on the subject. Your responses will be used solely for the intended purpose and be treated with utmost confidentiality. Thank you.
Please tick and fill the blank spaces appropriately
Section A: Demography
1. Age: 18-20 ( ) 21-30 ( ) 31-40 ( ) 41-50 ( ) 51-60 ( ) 61+ ( ) 2. Gender: Male ( ) Female ( ) 3. Level of education: No formal education ( ) Primary ( ) J.H.S ( ) S.H.S/A/O-Level ( ) Diploma ( ) Degree/HND ( ) Masters ( ) Any other, please specify…………
Section B: Knowledge about the Bui Dam and the Mammals
4. How long have you been living in this community? 4 yrs or less ( ) 5 -9 ( ) 10 – 14 ( ) 15 – 19 ( ) 20+ ( ) 5. Do you know where Bui Dam is? Yes ( ) No ( ) 6. Have you ever been to where Bui National Park is before? Yes ( ) No ( ) 7. Do you know the kind of mammals in the Bui National Park? Yes ( ) No ( ) 8. Name the large mammals in the Bui National Park you know: ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ………………………………………………………………
Section C: State of the Mammals in Bui National Park
9. Have you ever visited the Bui National Park before the Bui Dam was constructed? Yes ( ) No ( )
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10. If yes to q.9, how do you rate the state of the mammals after the Bui Dam‟s construction in the table below where 1=very poor or highly reduced, 2= poor or reduced, 3=the same or normal, 4= improved or increased, 5=very improved or highly increased Variable 1 2 3 4 5 number of mammals Mortality of mammals Composition Weight of mammals Water level Water pollution Prevalence of Human-wildlife interaction around the park Overall wellbeing as compared to others in other water bodies
89
Research Questionnaire for Staff and Management of Bui National Park
Preamble: I am a postgraduate student of Kwame Nkrumah University of Science and Technology. I am conducting a research to assess the post inundation effects of Bui Hydro Electric Dam on the large mammals in the Bui National Park. This research is in partial fulfillment of the requirements for the award of Masters of Science in Environmental Science. You have been selected to assist the study by providing candid answers to the following questions on the subject. Your responses will be used solely for the intended purpose and be treated with utmost confidentiality. Thank you.
Please tick and fill the blank spaces appropriately
Section A: Demography
1. Age: 18-20 ( ) 21-30 ( ) 31-40 ( ) 41-50 ( ) 51-60 ( ) 61+ ( ) 2. Gender: Male ( ) Female ( ) 3. What is your rank? Managerial ( ) Non-managerial ( ) 4. Level of education: No formal education ( ) Primary ( ) J.H.S ( ) S.H.S/A/O-Level ( ) Diploma ( ) Degree/HND ( ) Masters ( ) Any other, please specify…………
Section B: Knowledge about the Bui Dam and the Mammals
5. How long have you been working with Bui National Park authority? 4 yrs. or less ( ) 5 -9 ( ) 10 – 14 ( ) 15 – 19 ( ) 20+ ( ) 6. Do you know where Bui Dam is? Yes ( ) No ( ) 7. What is your rank? Managerial ( ) Non-managerial ( ) 8. Do you know the kind of mammals in the Bui National Park? Yes ( ) No ( ) 9. Name the large mammals in the Bui National Park you know: ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ………………………………………………………………
Section C: State of the Mammals in Bui National Park
10. Have you ever visited the Bui National Park before the Bui Dam was constructed? Yes ( ) No ( )
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11. If yes to q.9, how do you rate the state of the mammals after the Bui Dam‟s construction in the table below where 1=very poor or highly reduced, 2= poor or reduced, 3=the same or normal, 4= improved or increased, 5=very improved or highly increased Variable 1 2 3 4 5 number of mammals Mortality of mammals Composition Weight of mammals Water level Water pollution The prevalence of human-wildlife interaction around the park Overall wellbeing as compared to others in other water bodies
91
Management of BNP Questionnaire
Records of specific mammals before and after the inundation of the Bui Dam:
Number of live mammals before Bui Dam’s inundation Name of Jan Feb Mar April May Jun Jul Aug Sep Oct Nov Dec mammal 1. 2. 3. 4. 5.
Number of live mammals during Bui Dam’s inundation Name of Jan Feb Mar April May Jun Jul Aug Sep Oct Nov Dec mammal 1. 2. 3. 4. 5.
Number of dead mammals before Bui Dam’s inundation Name of Jan Feb Mar April May Jun Jul Aug Sep Oct Nov Dec mammal 1. 2. 3. 4. 5.
Number of dead mammals during Bui Dam’s inundation Name of Jan Feb Mar April May Jun Jul Aug Sep Oct Nov Dec mammal 1. 2. 3. 4. 5.
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Number of live mammals after Bui Dam’s inundation Name of Jan Feb Mar April May Jun Jul Aug Sep Oct Nov Dec mammal 1. 2. 3. 4. 5.
93