Observation of social organization, nesting and ecological interaction of termites in a semi-arid ecosystem

TABLE OF CONTENTS

DEDICATION

ACKNOWLEDGEMENTS

TABLE OF CONTENTS

Abstract

CHAPTER ONE INTRODUCTION AND LITERATURE REVIEW
1.1.0 Introduction
1.1.1 Background
1.1.2 Justification of the study
1.1.3 Objective of the study
1.1.4 Hypothesis
1.1.5 Statement of the problem

CHAPTER TWO MATERIALS AND METHODS
3.1 Methodology
3.1.1 Introduction
3.1.2 Study site
3.1.3 Description of vegetation and soils of study site
3.1.4. Socio-economic activities in the study site
3.1.5. Sampling techniques and observational studies
3.1.5.4. Feeding habits
.3.2 MATERIALS
3.2.1 Materials

CHAPTER THREE RESULTS AND DISCUSSION
4.1 Composition of termite groups
4.2 Social organization (workers and soldiers)
4.2.1. Reproductives (queen, king and alates (termite swarmers))
4.2.2. Workers
4.2.3. Soldiers
4.2.4. Diet
4.3. Termitogenic structures (Mounds and shelter tubes)
4.3.1. Shelter tubes
4.4. Mounds
4.4.1. Mound occurrence and shape
4.4.2. How the mound copes with temperature variation
4.4.3 Internal structures of the mound
4.3.4. Feeding and foraging
4.4.5. Vegetation cover around the mound

5.1. Ecological Interaction
5.1.1. Decomposition and nutrient cycling
5.1.2. Habitat for other organisms and breeding site

6.0. Conclusion

7.0. Reference

DEDICATION

I dedicate this project to future Ecologist, Conservation Biologist and anybody else who may find this work useful in whatever way to enhance their lives.

ACKNOWLEDGEMENTS

I would like to express my sincere appreciation to Dr. Wycliffe Wanzala for the inspiration provided by his work on termites and termite-based medicinal soils, for the field experiences and for his excellence as a supervisor. I would also like to appreciate my fellow college students and the entire staff of the Department of Biological Sciences, South Eastern Kenya University for their support. Lastly, in a special way, I wish to thank the following two people, Daniel Kariuki and Timothy Kimei for their selflessness and courage to accompany me in the scorching sun and their invaluable contribution in helping me make observations and conduct photography work in the field.

Abstract

Termites are eusosial organisms that have a profile of destructive and menacing organisms that serve an insignificant role in Earth’s ecology complex system. In the semi arid parts of Kenya, they are thought to be the primary cause of vegetation denudation especially during the dry seasons. Even after several years of Biology advancement its uncouth how most people have failed to appreciate the incredible role this animal perform in their niche for the benefit of humanity, especially in the inhospitable arid and infertile environments. Moisture shortage and the elevated temperatures characterize these regions, which has discouraged the survival of many decomposers in this environment leaving only a few species that have adapted to the conditions to survive, notably several species of termites. Water is life; this truth is not lost on these creatures. Some species of termites have evolved to such a level that they have the abilities to forage over unusual long distances and partially control their own dwelling environments, through the construction of nests structures in such a way that humidity and temperature does not vary all seasons. Termites create ingenious nests (mounds) from their waste materials and soils through tightly packing every particle together, creating waterproof corridors. For this reason, many have termed them as soil engineers. The termites’ ability to digest cellulose gives them advantage over other soil macro decomposers. This is enhanced by their mutualistic coexistence with certain bacteria in their gut that enables them to digest cellulose, which is the main constituent of their diet. Overall, Termites are most active soil macro inverts dominating the decomposition process in arid and semi arid environment during the dry seasons.

KEYWORDS: Mound, Ecosystem, Biostructures, Organization, Semi arid, Eusociality

CHAPTER ONE INTRODUCTION AND LITERATURE REVIEW

1.1.0 Introduction

Owing to the damage that termites cause through destruction wooden materials and vegetation cover all over the world, it is obvious to dislike them. For this reason, they have a reputation of being pests even among the scholars. For example, Thomas Snyder (1948) in the title of his book, Our Enemy the Termite, he continues to narrate this negativity notion about the termites. However, recent research and studies have begun to impact new knowledge in view of the termite biology. Scientists have engaged themselves in writing excellent articles and paper reviews probably due to the motivation from the role these organisms are playing in nature. Honestly, a creature that has been in existence on every continent in a plethora of habitats in the environments for millions of years ought to have a greater ecological niche than just a mere “pest.” Latest researches and follow-ups on the evolutionary trend of this order of insects sheds some light on the relationship between these organisms and environment describing their exact contribution for the years they have existed. The termites’ facity to adapt to arid environments has made them heroes for their very significant role of decomposition where common known kings of decomposition such as bacteria and fungi cannot withstand such hash conditions. Kitui east, which stretches to lower Yatta plateau in Kenya, could be an ideal area to study the interaction of Termites with the environment because of the low precipitation and elevated heat temperatures during the dry season. This observation study therefore aimed to contribute to such an effort, presenting an overview of the several ways termites engage with the ecosystem in their activities and the consequent effects this interaction would pose on ecosystem function on an ecological time scale. Profound knowledge of the social lifestyle of termites, nesting and their interaction with the ecosystem in terms of feeding habits and their different ecological strategies is a prerequisite for evaluating and quantifying the type and extent of their functional roles in ecosystem.

The studies were purely observations focused on evaluating the eusociality, nesting and interactive behaviours of different groups of termites in a semi-arid ecosystem. How this interaction impacts on the environment was also evaluated.

1.1.1 Background

Even though termites exist in many sizes and shapes taxonomically grouping of termites has been controversial, until recently, they were believed to constitute the order Isoptera. However, several taxonomic researches have proved that termites are indeed a type of cockroach and should be put the Order, Blattaria (Blattodea). It has been suggested Isoptera to remain unranked name within Blattaria until the phylogeny of cockroach is better resolved and a proper ranking is reached. For this reason, termites can be placed under Kingdom: Animalia, Phylum: Arthropoda, Class: Insecta, and Order: Isoptera (Momer, 2003). Currently, worldwide species count is 2,761. Of these species, 1,958 are higher termites (Myles, 2003). Lower termites can be defined as a group of six families sharing the presence of symbiotic intestinal flagellates. Higher termites exhibit more advancement in terms of evolution than lower termites in that they have lost the flagellate protozoa and substituted them with bacteria. Higher termites constitute three quarters of all known termite species, many species are yet undescribed according to Myles (2003).

1.1.2 Justification of the study

The rate at which termites are spreading in the semiarid parts of Africa, Kenya being not an exemption, is alarming and the damage they are causing on wood tree is just overwhelming, leading to decline of indigenous trees species and destruction of agricultural structures in this regions (Collins, 1990).

The study has been necessitated by the quest to control the situation and need to understand termites and their role in ecology as their effect cannot be overlooked because they are already bare and significantly felt in the economy of the country.

Understanding local termite composition structure and their feeding habits will assist in policy making at county and nationwide level if the study is adopted and this will enable concerned government institutions such as Kenya Forest Research Institute (KEFRI), Kenya Agricultural Institute (KARI) and in collaboration with Kenyan universities to come up with better measures and mitigation practices on termites.

1.1.3 Objective of the study

To study the eusociality, nesting and interactive behaviors of different groups of termites in a semi-arid ecosystem.

1.1.3.1 Specific objectives

1. To evaluate the social organization of different groups of termites in a semi-arid ecosystem with respect to reproductive’s, workers, soldiers, and diet.
2. To evaluate nests of different groups of termites in a semi-arid ecosystem with respect to mounds and shelter tubes.
3. To make an observation of the effects of the interaction of different groups of termites in their respective ecological niches

1.1.4 Hypothesis

“Knowledge about eusociality, nesting and interactive behavior of different groups of termites in their respective ecological niches is crucial in their sustainable control, prevention and management as pests.”

1.1.5 Statement of the problem

Termite infestation is causing loss of biodiversity in these semi arid parts. Almost every tree species here in Kitui County has become a victim of this pest. According to Sekamatte (2001), they are attacking trees in discriminatively unlike in other parts where the only indigenous species targeted is the Acacia spp.

The communities living in these areas largely depend on forest products as source of their livelihood and pasture grounds for their livestock. Extensive ground cover denudation by termites during the dry season in particular, by termites leads to scarcity of food for the animals and it is of concern to many. To restore the situation proper understanding of termites will be of great importance.

1.2 Literature review

Termites are eussocial insects, that is, insects that live in colonies composed of individuals (I) from more than one generation (e.g. parents and offspring), (ii) presenting cooperative care of the young and (iii) showing reproductive division of labor. Termite colonies are normally composed of a reproductive pair (king and queen) and their offspring comprising thousands of non-reproductive individuals. Eventually, the reproductive pair originates reproductive offspring, which swarm out of the nest to establish a new colony. A termite colony, therefore, can be grouped into morphological castes, which according (Desouza et al, 2009) it can also be the reproductive (king, queen and their reproductive offspring) or sterile (workers and soldiers). As with other biological systems, exceptions apply: Neotropical Apicotermitinae (Termitidae) termites do not possess soldiers, and Kalotermitidae and Termopsidae (traditional sense or Archotermopsidae in the new classification) do not possess true workers. Instead, their immature nymphs do most of the tasks of the colony.

Such nymphs (called pseudergates) present very plastic development pathways, staying in this phase by stationary molts or differentiating into either soldiers or secondary reproductive’s (with wing buds). As a rule, workers perform most of the tasks that keep the colony running smoothly, including caring for the royal couple and nest mates, foraging, repairing the nest, and defending the colony. Soldiers, in their turn, are more specialized in the colony’s defense. Some species (including all Kalotermitidae and Termopsidae, plus some Rhinotermitidae) live within wood. Others, among which include some Rhinotermitidae and some Termitidae, live inside the soil matrix in nests that are better described as diffuse gallery systems. Some (e.g., Termitidae Procornitermes spp.) build very architecturally complex nests, albeit completely subterranean. Others, while keeping intricate gallery systems inside the soil, still build mounds emerging from the soil surface (Fleming and Loveridge, 2003). Among those, the Termitidae Syntermes spp. build loose earthen mounds whose major portion rests within the soil and no cemented walls are distinguishable above the soil surface. Cornitermes spp. and Macrotermes spp. (both Termitidae), in their turn, are well known examples of creating highly structured nests with hard walls built from a mixture of clay, saliva and feces, whose major portion is seen above the soil surface (Grass, 1982). Such structures are normally called termitaria. In addition to being their builder’s colony, termitaria can also shelter other organisms or are important nutrient hotspots for plants and their associated fauna. Termitaria, therefore, have a potential ecological role that cannot be disregarded. Some very specialized termite species do not build their own nests but live exclusively inside other termites buildings; well known examples being the Serritermes serrifer (Serritermitidae) and Inquilinitermes spp. (Termitidae) (Grass,1986). These are called inquilines, a term that also applies to those termite species that are able to build their own nests but are facultative termitaria invaders. Termite nests may also house microbes, plants, invertebrates and vertebrates, which are called termitophiles or termitariophiles, depending respectively on whether they are associated to the host or to the termitaria itself according to Joquet et al (2002).

A part from those species that live inside wood or those that are strict inquilines, termites need to leave their nests in order to look for food. Most species do so within subterranean tunnels or mud galleries built on the surface which acts as an extension of their nests (e.g. Hospitalitermes spp. and systems and a few others).

CHAPTER TWO MATERIALS AND METHODS

3.1 Methodology

3.1.1 Introduction

This will entail thorough fieldwork, observations and analysis of several documentaries on termite biology and ecology in a semi-arid ecosystem, with special focus on Yatta Plateau in Kitui County in Kenya.

3.1.2 Study site

Figure 1. Showing location of Kitui County on the map of Kenya, where the study site (within the compound of South Eastern Kenya University located at Lower Yatta Plateau) was conducted.

3.1.2.1 Description of the study area

Yatta plateau is located at -1.2500000 (latitude in decimal degrees), 37.5833300 (longitudes in decimal degrees). It is located on Eastern, Kenya with an elevation of 922 m height above sea level (Bernard and Thom 2011; Wisner, 2000). The study will be conducted specifically in SEKU, which is located in Kitui County, Lower Yatta Plateau. Kitui is located on a predominantly semi-arid, eastward-facing slope, which becomes progressively lower and drier to the east. It is part of Kenya's Eastern Foreland Plateau, which is an eroded basement complex broken by residual hill masses and occasionally overlain by tertiary volcanics (Bernard and Thom, 2011; Wisner, 2000).

This part of Kenya forms an environmental gradient of decreasing altitude (from 2,100 m to 440 m), increasing temperatures, and decreasing moisture (from 1,270 to 381 mm average annual rainfall) from west to east (Ojany and Ogendo, 1999; Owako, 2000; Porter, 2011). Elevation controls the quantity of rainfall at the regional scale, whereas topography strongly influences rainfall distribution at the local scale. The rainfall cycle is bimodal, with long rains coming between March and May and short rains from October to December (Moore, 2003; Porter, 2000).

3.1.3 Description of vegetation and soils of study site

3.1.3.1 Description of vegetation

The dominant vegetation of this part of Kenya is dry bushy trees, and, in the higher areas, savanna with scattered trees (Ominde, 2001). The hills were once forested, but by the beginning of the colonial period most of the "desirable" agricultural land had been cleared (Harroy, 2000; Owako, 2000; Silberfein, 1999). Characteristic vegetation at the higher altitudes (above 1,700 m) includes remnant evergreen forest (Podocarpus spp.) and bracken, mist forest, and evergreen thicket clumps in grassland. Combretum species, with particular plant associations correlated with topography and moisture dominates elevations at 1,200-1,700 m. The most widespread vegetation type in this area especially, Kitui semi-arid deciduous thicket and bushland, particularly Acacia/Commiphora associations in the 8001,200 m elevation range. In the dry areas below 900 m, Commiphora/Sanseveria thorn bush grades into semi-desert vegetation (Ojany and Ogendo, 1999; Owako, 2000).

3.1.3.2. Description of soils

The soils of Lower Yatta Plateau and the rest of Kitui County reflect the largely metamorphic parent material and the rainfall regimes that contribute to their formation (Barber et al., 2003; Ojany and Ogendo, 1999). In Kitui County, the dominant soil groups are alfisols, ultisols, oxisols, and lithic soils (Barber et al., 2003; Lerberg, 2002). These soils are all generally of low fertility, and many are highly erodible (Barber et al., 2003). The ultisols and alfisols are also susceptible to sealing (capping), which increases runoff and makes the clay soils hard to plough by the end of the dry season (Barber et al., 2003). A rough estimate of the agricultural quality of the region's soils indicates that less than 20 per cent of Kitui County has well-drained, deep, friable red and brown clays of good fertility. More than 60 per cent of the region has very erodible, relatively shallow, sticky, red, black, and brown clays of variable fertility, on steep slopes; 20 per cent has poorly drained, shallow, stony soils of low fertility (Bernard et al., 2003).

3.1.4. Socio-economic activities in the study site

Resources: Arable land, Wildlife, Livestock, Forests, Minerals (Large deposits of Coal and limestone in Mui basin and Mutomo/Ikutha respectively).

Tourist Attractions: Mwingi National Reserve, Kora National Reserve, and Tsavo East National Park.

Main Economic Activities/Industries: Livestock keeping, Tobacco, Cotton, Mangoes, and Commercial Businesses, Agricultural Products: Livestock Products, Maize, Beans, Sorghum, Pigeon peas, Cowpeas, Cassava, Millet, and Green grams.

3.1.5. Sampling techniques and observational studies

Random sampling was done within South Eastern University Kenya, which has vast land of 10, 000 hectares, significant to act as representative of the lower Yatta. The sampling technique used was maximum variation sampling technique, which is a qualitative technique, the reason being it selects a wide range of variation on dimensions of interest, which are the specific objectives. The purpose of using this technique is to allow the researcher to discover/uncover central themes, core elements, and/or shared dimensions that cut across a diverse sample while at the same time offering the opportunity to document unique or diverse variations.

3.1.5.1. Fieldwork

Taking photos in the field, short notes, in the field using a camera with special focus on, Social organization system of the termites, their nesting and feeding habits including vegetation, accompanied the observation and soils around the mound were of much significance in achieving the specific objectives.

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