WILDLIFE BIOLOGY 3(2+1)
What is wildlife?
Wildlife includes all non domesticated plants, animals, and other organisms. It has many values that may be both positive and negative.
Positive values of wildlife:
1. Physical utility: use of wildlife for food, clothing, and other domestic uses. 2. Economic/Monetary value: Furs, hides, ivory, medicines. 3. Recreational value: Bird watching, parks, tourism 4. Scientific value: Development of research, discovery and invention of new things 5. Ecological value: cycling of water, nutrients and pollution reduction. 6. Existence value: it is the potential to become valuable in future. It helps in the preservation of genetic diversity.
Negative Values:
1. Wildlife damage: it includes damage to agricultural crops, livestock and timber. 2. Human animal conflict: it results in human injuries and illnesses. 3. Loss of economic productivity: grazing, damage to plantation 4. Wildlife diseases to man 5. Competition effect CLASSIFICATION OF MAMMALS
Mammals are defined as vertebrates that possess hairs and mammary glands for feeding young. They also possess a four-chambered heart, a large cerebral cortex, three distinctive bones: incus, malleus and stapes in the middle ear, a diaphragm for breathing, heterodont and thecodont dentition, limbs attached under the body, dicondylic skull and acoelous vertebrae. The class Mammalia is classified into three subclasses, 28 Orders, 161 Families, 747 Genera and 4939 Species. 1. Subclass PROTOTHERIA (Egg-laying mammals): It includes I order consisting of 2 families of mammals that lay eggs with leathery shells and nourish the young with milk from primitive mammary glands. They possess a cloaca like reptiles, have no urinary bladder but possess hairs. Order Monotremata : Family Ornithorhynchidae, Tachyglossidae Examples include: Platypus, ant eaters 2. Subclass METATHERIA (Marsupial mammals) Includes about 300 species grouped under about 240 genera and 15 families, whose young are born in immature state and then reared in pouches called marsupium. Found in Australia and South America. Opossum has now spread to North America. Order Marsupialia: Body covered with fur; pinna well developed; female with marsupium; tympanic bulla absent; diaphragm and seven cervical vertebrae are present and the marsupial bone (epipubis) present. Families: Didelphidae, Thylacinidae, Dasyuridae, Myrmecobiidae, Notoryctidae, Peramelidae, Thylacomyidae, Caenolestidae, Phalangeridae, Burramyidae, Petauridae, Macropodidae, Phascolarctidae, Vombatidae, Tarsipedidae, 3. Subclass EUTHERIA (Placental mammals) These are true mammals which are completely viviparous, with chorio-allantoic placenta and in which complete development takes place in uterus. It consistes of the following orders: i. Order Insectivora: Families included are: Erinaceidae, Talpidae, Tenrecidae, Potamogalidae, Chrysochloridae, Solenodontidae, Solenodon, Soricidae, Macroscelididae, Tupaiidae ii. Order Chiroptera: Families included are: Pteropodidae, Rhinopomatidae, Emballonuridae, Nycteridae, Megadermatidae, Hipposideridae, Rhinolophidae, Noctilionidae, Mormoopidae, Phyllostomatidae, Desmodontidae, Natalidae, Furipteridae, Thyropteridae, Myzopodidae, Vespertilionidae, Mystacinidae, Molossidae, iii. Order Dermoptera iv. Order Rodentia: Families included are: Aplodontidae, Sciuridae, Cricetidae, Muridae, Heteromyidae, Geomyidae, Zapodidae, Dipodidae, Spalacidae, Rhizomyidae, Octodontidae, Echimyidae, Ctenomyidae, Abrocomidae, Chinchillidae, Capromyidae, Dasyproctidae, Dinomyidae, Caviidae, Hydrochoeridae, Erethizontidae, Petromuridae, Thryonomyidae, Bathyergidae, Hystricidie, Castoridae, Ctenodactylidae, Pedetidae, Gliridae, Seleveniidae. v. Order Edentata: Families included are: Myrmecophagidae, Bradypodidae, Dasypodidae. vi. Order Pholidota vii. Order Tubulidentata viii. Order Lagomorpha: Families are: Ochotonidae, Leporidae. ix. Order Carnivora: Families Included are: Canidae, Ursidae, Otariidae, Procyonidae, Mustelidae, Weasels, Phocidae, Felidae, Viverridae, Hyaenidae, x. Order Cetacea: Families are: Balaenidae, Eschrichtiidae, Balaenopteridae, Platanistidae, Delphinidae, Phocoenidae, Monodontidae, Physeteridae, Hyperoodontidae, Stenidae, xi. Order Proboscidea: Family Elephantidae, xii. Order Sirenia: Families: Dugongidae, Trichechidae, xiii. Order Hyracoidea xiv. Order Perissodactyla: Families are: Equidae, Tapiridae, Rhinocerotidae. xv. Order Artiodactyla: Families are: Tragulidae, Antilocapridae, Giraffidae, Cervidae, Bovidae, Camelidae, Suidae, Tayassuidae, Hippopotamidae, xvi. Order Primates: Families are: Lemuridae, Cheirogaleidae, Indriidae, Daubentoniidae, Lepilmuridae, Galagidae, Lorisidae, Tupaiidae, Tarsiidae, Callithricidae, Cebidae, Cercopithecidae, Hylobatidae, Pongidae, Hominidae. BASIC REQUIREMENTS OF WILDLIFE: Food:
All animals require food and shelter for their survival. Different statures of food as a base for wildlife management have been discussed under the following heads:
1. Food Chain 2. Food web 3. Food pyramid/Ecological Pyramid
The food requirements of a particular community depends upon:
Physiology and digestive ability of the community Instictive selection patterns of food Season and behaviour Shelter and habitat
Water:
All animals need water for thei survival. The water requirements of a particular community depends upon the following variables:
Food and feeding habits Availability of water Shelter and habitat Climatic conditions
Shelter:
Shelter refers to the quality and quantity of arrangements of essential needs for the existence of an animal or community in an area. It performs the following functions:
Affords protection against adverse climatic conditions Ensures protection against enemies Ensures availability of food and water Provides suitable breeding facilities Satisfies the instinctive and psychological needs
Space:
It is a basic requirement for all wildlife to forage, seek cover, protect their young, and have access to diverse habitat conditions. Space is of two types:
1. Territory: It is an area of the forest taken up by an individual for the following functions: To meet its requirements of food and shelter To serve as a breeding ground To meets its psychological needs 2. Home Range: It is an area over which an animal roams without the tendency to exclude others from it.
Limiting factors for wildlife
According to the concept of limiting factors, if an environment factor exceeds the maximum tolerable level or comes down below the minimum tolerable level in an area, it limits the distribution of a particular species or a group of species in an area. These factors are called as Limiting factors for Wildlife. The limiting factors for wildlife are:
1) Law of Minimum:
It is related to the concept of limiting factors and was proposed by Liebig in 1840 and states that “The growth of plants is dependent on the amount of food and other requirements needed by it in minimum quantities”. This is equally true for wild animals. A minimum level of requirements of food, water and shelter are needed for their survival in a particular area.
2) Law of Tolerance: This law was advanced by Shelford in 1913. According to it, “The availability of a necessity below or above a certain limit may also affect the abundance or growth of species”.According to this law, all environmental factors determine a tolerance level in relation to a particular species or a group of species. There is also a critical minimum level and Critical maximum level. This zone of tolerance may be divided into: i. Lower limit of tolerance ii. Zone of physiological stress iii. Optimum range
3) Zone of physiological stress This is a transition zone near the lower limit of tolerance in which the distribution of a apecises is infrequent.
4) Lower limit of tolerance: This is the lowest limit of tolerance of an environmental factor.
5) Upper limit of tolerance: This is the highest limit of tolerance of an environmental factor.
Very often a single limiting factor is not involved in a complete community. A combination of such factors play a limiting role. Hence, it may be concluded that the presence of a group of species in an ecosystem depends on a combination of complex factors. Any factor or combination of factors that approaches or exceeds the limit of tolerance is a limiting Factor. In Nature, the survival of an organism is governed by:
The physical factors that are available The quality and variability of the material for which there is minimum requirement The limits of tolerance of the organisms to various factors. FOOD CHAIN AND FOOD WEB
A food chain is linear sequence of organisms which starts from producer organisms and ends with decomposers. In scientific terms, a food chain is chronological pathway or an order that shows the flow of energy from one organism to the other. The components of a food chain are:
1) The producers: Plants are the producers in a food chain that produce the food autotrophically with the help of sunlight. They occupy the first trophic level in a food chain. 2) The consumers: consumers are those animals which feed on producers are directly or indirectly. There are three types of consumers i. Primary consumers: those organisms which feed directly on the producers are called primary consumers. It includes all the herbivores. ii. Secondary consumers: Those organisms which feed on the primary consumers are called secondary consumers. iii. Tertiary consumers: Organisms which feed on the secondary consumers are called tertiary consumers.
3) The Decomposers: these are microorganisms which feed on the dead and decaying matter and release the nutrients back into the soil.
Salient Features of a food Chain:
It is always unidirectional It follows the second law of thermodynamics. It follows the ten percentile law. Plants always occupy the first trophic level in a food chain.
A food web is the intermingling or a mixture of several food chains. It is the realistic representation of the energy flow through an organism in an ecosystem.
Salient features of a food web:
It is multidirectional. It represents the realistic view of the energy flow in an ecosystem.
A food chain or food web consists of several levels at which the organisms are placed. These levels are called the trophic levels. ECOLOGICAL PYRAMIDS:
The pyramidal representation of trophic levels of different organisms based on their ecological position (producer to final consumer) is called as an ecological pyramid. The pyramid consists of a number of horizontal bars depicting specific trophic levels. The length of each bar represents the total number of individuals or biomass or energy at each trophic level in an ecosystem. The food producer forms the base of the pyramid and the top carnivore forms the tip. Other consumer trophic levels are in between. The ecological pyramids are of three categories:
1. Pyramid of numbers, 2. Pyramid of biomass, and 3. Pyramid of energy or productivity.
1. Pyramid of Numbers
Pyramid of numbers represents the total number of individuals of different species (population) at each trophic level. Depending upon the size, the pyramid of numbers may not always be upright, and may even be completely inverted. It is very difficult to count all the organisms, in a pyramid of numbers and so the pyramid of number does not completely define the trophic structure for an ecosystem.
Pyramid of numbers – upright
In this pyramid, the number of individuals is decreased from lower level to higher trophic level.
This type of pyramid can be seen in the grassland ecosystem and pond ecosystem. The grasses occupy the lowest trophic level (base) because of their abundance. The next higher trophic level is primary consumer – herbivores like a grasshopper. The individual number of grasshoppers is less than that of grass. The next energy level is a primary carnivore like rats. The number of rats is less than grasshoppers, because, they feed on grasshoppers. The next higher trophic level is secondary carnivore like snakes. They feed on rats. The next higher trophic level is the top carnivore like Hawk. With each higher trophic level, the number of individual decreases.
Pyramid of numbers – inverted
In this pyramid, the number of individuals is increased from lower level to higher trophic level. E.g. Tree ecosystem.
2. Pyramid of Biomass
Pyramid of biomass is usually determined by collecting all organisms occupying each trophic level separately and measuring their dry weight. This overcomes the size difference problem because all kinds of organisms at a trophic level are weighed. Each trophic level has a certain mass of living material at a particular time called the standing crop. The standing crop is measured as the mass of living organisms (biomass) or the number in a unit area.
Pyramid of Biomass – upright
For most ecosystems on land, the pyramid of biomass has a large base of primary producers with a smaller trophic level perched on top. The biomass of producers (autotrophs) is at the maximum. The biomass of next trophic level i.e. primary consumers is less than the producers. The biomass of next higher trophic level i.e. secondary consumers is less than the primary consumers. The top, high trophic level has very less amount of biomass.
Pyramid of Biomass – Inverted
In contrast, in many aquatic ecosystems, the pyramid of biomass may assume an inverted form. (In contrast, a pyramid of numbers for the aquatic ecosystem is upright) This is because the producers are tiny phytoplankton that grows and reproduces rapidly. Here, the pyramid of biomass has a small base, with the consumer biomass at any instant exceeding the producer biomass and the pyramid assumes an inverted shape.
3. Pyramid of Energy
To compare the functional roles of the trophic levels in an ecosystem, an energy pyramid is most suitable. An energy pyramid represents the amount of energy at each trophic level and loss of energy at each transfer to another trophic level. Hence the pyramid is always upward, with a large energy base at the bottom.
Suppose an ecosystem receives 1000 calories of light energy in a given day. Most of the energy is not absorbed; some is reflected to space; of the energy absorbed only a small portion is utilized by green plants, out of which the plant uses up some for respiration and of the 1000 calories; therefore only 100 calories are stored as energy-rich materials. Now suppose an animal, say a deer, eats the plant containing 100 calories of food energy. The deer use some of it for its metabolism and stores only 10 calories as food energy. A lion that eats the deer gets an even smaller amount of energy. Thus, usable energy decreases from sunlight to producer to herbivore to carnivore. Therefore, the energy pyramid will always be upright. Energy pyramid concept helps to explain the phenomenon of biological magnification – the tendency for toxic substances to increase in concentration progressively with higher trophic levels. WILDLIFE ECOLOGY
Wildlife Ecology is the science behind the practise of wildlife management that seeks to manage wildlife populations for the benefit of humans. It has become progressively more quantitative especially since the 1990s; even so it retains a strong orientation towards techniques with an emphasis on statistical measures rather than ecological principles. It has converged as essentially a sub-discipline of conservation biology focused largely on the applied ecology and management of wild populations of birds and mammals.
Ecology is not restricted to the domains of plants and animals. It also draws heavily upon other fields such as climate, chemistry, geography, etc.
Wildlife Ecosystem:
An ecosystem is the basic fundamental unit of organisms and their environment, interacting with each other and within their own components. The main components of an ecosystem are:
1) Abiotic substances: These are the non-living constituents of the ecosystem like carbon dioxide, Oxygen, water, etc. 2) Biotic components: It consists of 3 categories: i. Producers ii. Consumers iii. Decomposers
(as discussed earlier)
ABIOTIC FACTORS:
These can be further divided into 3 categories:
i. Environmental factors ii. Edaphic factors iii. Hydrological; factors
ENVIRONMENTAL FACTORS
1) Light:
The main source of natural light are Sunlight, moonlight, light from stars and light from luminescent animals. Of these, solar enery is the most important source of light. Sunlight reaching the earth provides life and warmth to the cold blooded animals like amphibians.
As like plants, animals require specific light duration and intensity for their regular metabolic activities. Based n the light requirements, animals are classified as follows:
1) Long Day Animals : Spring Breeding Birds, turkeys, starlings 2) Short-day Animals : Deer, sheeps, goats 3) Indifferent dat length Animals : Squirrels Naturally, Animals have their own morphological adaptations according to the light conditions. For Example, eye of the deep sea animals and fishes are larger in size whereas animals living in high light intensity areas (desert region) has smaller eyes.
2) Temperature:
Temperature refers to the relative coolness or hotness of an object. Animals are temperature sensitive too. Animals in cold region have smaller ear, compact neck, and thick fur whereas animals living in hot climate have bigger ear, and thin fur. Based on temperature, animals are classified as Eurithermal & Stenothermic animals. Temperature is of three types:
Maximum temperature Minimum temperature Optimum temperature
Of these, optimum temperature is the most important temperature range because it is temperature at which vital processes in animals and plants take place.
3) Relative Humidity
It is the quantity of water vapour present in the animal expressed as a percentage of the Quantity present in the air at the same temperature.
4) Wind
It is another important environmental factor that plays a role in the ecology of wildlife. It has the following features:
Wind usually blows from high pressure zones to lower pressure zones In the hills, gravity winds blow towards the valley in the evening and vice versa in the early morning. Strong winds blow in open areas.
5) Rainfall
It is the main constituent of total annual precipitation. Others are:
Drizzle: A form of precipitation in which small drops of water appear to float in the atmosphere Due and Frost: this involves the condensation of moist air on the earth’s suface. Hail: The precipitation of moisture in the form of balls or lumps of ice Snow: It is the combination or collection of ice in the form of hexagonal crystals
HYDROLOGICAL FACTORS:
Water:
Water is essential for all kinds of metabolic and chemical reactions that are going on in the body of any plant or animal. The different phases of water circulation are:
Precipitation Evapotranspiration Transpiration Perspiration Drainage
EDAPHIC FACTORS:
Soil:
Soil is the shallow upper layer of the earth. It performs the following functions;
It provides support, water, nutrients and oxygen for all plant growth It is a basic constituents of abiotic components of the ecosystem All plants and animals depends on the soil forming a complex food chain together with herbivores, carnivores, predators and prey.
BIOTIC FACTORS:
Biotic factors are a result of Interaction among different individuals of the same or different species. No living organism can live in isolation in an ecosystem. It is interlinked and interdependent on others for the following purposes.
Food and Water Shelter and Protection To maintain its niche in the ecosystem
Interdependence exists between animals of the same or different species. It is of two types:
I. Intra-specific relationship: This is the ecological relationship between Individuals of the same species within the same ecosystem.
II. Inter-specific relationship: This is the ecological relationship between Individuals of the different species within the same ecosystem. Inter-specific relationship is of three types: a) Neutralism: In this case none of the species have effect on each other b) Symbiosis: In this case, both parts get mutual benefit and there is harm to none. It is further divided into Mutualism and Commensalism. c) Antagonism: In this case, both or one of the Partner, causes adverse effect on the relationship. It can be further divided into Parsitism, Predation , Competition and Ammensalism PRODUCTIVITY
The rate of Bio mass production is called Productivity. It pertains to the actual reproduction of a particular species.
Productivity= Breeding Potential- Environmental Resistance
From the above formula, it is clear that two factors have a bearing on productivity:
Breeding Potential:
It is the capacity or capability of a organism to produce off springs irrespective of the proportion that is able to survive to maturity. It is primarily a theoretical concept related to ideal conditions of Breeding and reproduction.
Environmental Resistance:
This pertains to the resistance offered by a host of environmental factors that restrict the biological expansion of a species. The main environmental factors are:
Predation Climate Diseases Survival of the fittest Non breeding Accidents EFFECT OF LIGHT AND TEMPRETURE ON ANIMALS:
1. LIGHT:
Light has many effects in plants and animals. There are composite of various factors which are generated due to the presence, absence or intensity of light. Some of the effects of light are:
1) Metabolism: the metabolic rate of animals is affected by the intensity and duration of light.
2) Growth: there is a direct relation between metabolism and growth of animals. Light influences metabolism, thus it has a very important effect on the growth and development of an animal. The growth and development of many species is better in life.
3) Reproduction: breeding and reproduction in many animals is initiated and controlled by light which brings about stimulation at their own.
4) Skin colour: Light has an effect on the colour of the skin of the animals. A number of photoreceptor chemical pigments are formed due to the effects of Light. These pigments perform the following functions:
Influence the skin colour of animals Camouflage
5) Eyes: Intensity of light influences the size of eyes of many animals.
Effect of temperature on Animals:
Temperature influence metabolic rates Temperature influence reproduction of animals Temperature influence distribution of animals Temperature influence structure of animals: compact tailed ear neck in animals of cold regions whereas larger neck tail and ear in animals of tropical climate. WILDLIFE HABITAT
Wildlife Habitat is a combination of food, water, shelter, and space arranged to meet the needs of wildlife. Even a small yard can be landscaped to attract birds, butterflies, beneficial insects, and small animals. Trees, shrubs, and other plants provide shelter and food for wildlife.
Wildlife Habitat depends on the following:
1. Niche: It is used to define an organisms role in an ecosystem. Not only does it include the environment that a given organism lives in but also includes the organisms “Jobs” in that environment. It may also encompass what the organism eats, how it interacts with other living and non living aspects of the environment.
2. Carrying Capacity: the carrying capacity of an area is defined as the maximum number of organisms that an ecosystem can support with its minimal supply of food. The carrying capacity of an area having adequate sources of food can be enhanced by increasing the water points. On the other hand, too many water points will attract an unsual number of animals thus creating a risk of habitat destruction
3. Territory: It is an area of the forest taken up by an individual for the following functions: To meet its requirements of food and shelter To serve as a breeding ground To meets its psychological needs
4. Home Range: It is an area over which an animal roams without the tendency to exclude others from it.
5. Edge: Edge effects are the result of an abrupt transition between two significantly different natural habitats that are adjacent to each other. In essence, it is a break in continuity between two adjacent habitats, leading to changes in the environmental and biological conditions. Generally, the edge of two habitats supports greater diversity of organisms than both the habitats individually.
6. Cruising Radius: It is defined as the distance that an animal can cover from an initial point in the course of the day. 7. Interspersion: This pertains to the mixture of a number of species or type of vegetation that occurs over an edge. ANIMAL BEHAVIOUR AND ADAPTATION
ANIMAL BEHAVIOUR
It is the scientific study of the wild and wonderful ways in which animals interact with each other, with other living beings , and with the environment. It explores how animals relate to their physical environments as well as to other organisms, and includes topics such as how animals find and defend resources, avoid predators, choose mates reproduce and care for their young ones. Animals show the following behavioral attributes:
1. Territoriality: It is a type of Intra specific or interspecific competition that results from the behavioural exclusions of others from a specific space that is defended as territory. Though it offers immense reproductive and nutritional benefits, it also comes at a cost. Territoriality costs time and energy and can often interfere with other fundamental activities such as parenting, feeding, courting and meeting. 2. Predation: this pertains to the preying of one animal on the other. In the absence of predation the expansion of organisms at the base of the pyramid would be so much that there would be no space left for others to survive. There are three types of predation: i. Chance predation: occasional or casual predation, as seen in omnivores ii. Habit predation: All predators prey regularly on prey species. This helps to control surplus or extra numbers and does not have adverse effect on population density. iii. Sanitary predation: Predators prey upon the dying and diseased individuals of a species. 3. Gregariousness: There is a tendency in many animals to stay together, which is known as gregariousness. Individuals of the same species prefer to hunt and live in small groups. Animals which exhibit gregariousness include deers and antelopes, monkeys, elephants, etc. On the other hand many animals prefer to live alone. These are known as loners. 4. Flocking: Flocking is an indicators of gregariousness. It pertains to the living together of a number of groups of individuals of the same species during a particular period. Some of the factors whih indicate the size of flock are: i. Differences in age ii. Requirements of space, food and cover iii. Competition and predation 5. Pecking order: it is a system of social dominance that has evolved in most species showing gregariousness and flocking and is based on relative strength. The most powerful individual of the herd is usually the leader. The leader of the herd usually performs the following functions: Services as a sentinel Decides the routes and areas of the of the herd or flock for feeding Its actions are usually unchallenged 6. Animal migration: the movement of animals from one place to another is called as migration. The following are some causes responsible for migration: Better habitats or living conditions in winter In search of food. To avoid adverse conditions such as heavy snow fall For breeding Animal migration may be of the following types:
i. Local migration: this pertains to the migration in which the distance travelled is not very large ii. Long distance migration: this pertains to the migration in which the distance travelled is very large iii. Altitudinal migration: in the hills, animals migrate to higher elevations in summer and come down to the shelter of valleys in winter. 7. Intra-specific Relationship 8. Inter-specific relationship 9. Adaptation: An adaptation is a way an animal's body helps it survive, or live, in its environment. Camels have learned to adapt (or change) so that they can survive. More is Discussed in the next section.
ADAPTATIONS
An adaptation is a way an animal's body helps it survive, or live, in its environment. Adaptation is defined as the process where a species or an organism gradually becomes better acclimated to its environment. It can also be defined as the structural, physiological and behavioral features that organisms develop which enable them to survive and reproduce successfully in the environment.
There are types of adaptations:Structural adaptation, Behavioral adaptation and Physiological adaptation
Structural: An organism's environment shapes its appearance through structural adaptations. Desert foxes have large ears for heat radiation and Arctic foxes have small ears to retain body heat. Seals have flippers to navigate water and raccoons have separate, flexible digits to manipulate food. White polar bears blend into ice floes and spotted jaguars into the speckled jungle shade. Trees may have corky bark to protect from wildfires. Structural modifications affect organisms at different levels, from the way a knee is hinged to the presence of large flight muscles and sharp eyesight for predatory birds. Physiological: Based on body chemistry and metabolism, physiological adaptations usually don't show from the outside. They consist of things like more efficient kidneys for desert animals like kangaroo rats, compounds that prevent blood coagulation in mosquito saliva, or the presence of toxins in plant leaves to repel herbivores. Laboratory studies that measure the contents of blood, urine and other body fluids, that trace metabolic pathways, or microscopic studies of an organism's tissues are often necessary to identify physiological adaptations. Sometimes detecting them is difficult if there isn't a common ancestor or a closely related species with which to compare findings. Behavioral: Adaptations that affect how an organism acts are called behavioral adaptations. Bears hibernate to escape cold; birds and whales migrate to warmer winter climates. Desert animals are active at night during hot summer weather. Lizards seek a sunny spot in the morning to warm up to operating temperatures more quickly. A nesting killdeer will pretend to be injured to lure a predator away from her young. Behavioral adaptations that involve mating procedures, such as that exhibited by the Australian bowerbird, can be amazingly complex. Often behavioral adaptations take careful field and laboratory studies to bring them fully to light, and often involve physiological mechanisms as well. Humans employ cultural adaptations as a subset of behavioral adaptations, where people who live in a given environment learn ways of raising the food they need and coping with the particular given climate. HABITAT IMPROVEMENT
Habitat improvement is done in order to develop, preserve, restore, enhance and/or manage wildlife habitat on a piece of land. The main goals of habitat improvement are to create a better wildlife habitat while keeping in mind the concept of sustainability. A habitat can be improved by following the under mentioned areas:
Edge of the habitat should be suitably improved Nut and fruit trees should be planted Woody cover and hedgerows are planted continuously
Habitat Improvement also involves the improvement in the following sections:
1. Food 2. Water 3. Shelter 4. Wetland 5. Predation 6. Tourism
All the above concepts are mentioned as under:
1. Food Improvement:
Food improvement can be achieved through the following means:
Planting of fruit and fodder trees to meet the requirements of birds and grazing animals. Trimming of tree canopies to yield more fruits and fodder 2. Water Improvement:
It can be achieved through the following:
Water hole: Water holes of suitable sizes are made inside the forest areas. This should satisfy all kinds of animals. In case of natural water holes, it should be deepen and raise the edge level. Polythene lining of bottom is provided to reduce the seepage loss of water. Man made holes are the artificially created water holes which are made according to the improvement needs. Rivers and streams: These are obstructed and suitably designed for animal drinking purposes. Springs are also managed in the same way. Reservoirs and Ponds: these are managed in such a way that water is harvested and stored during rainy season in large quantum. This should be used during the summer season. Self filling water devices: Guzzlers are self filling water devices which is similar to the cistern. In this water tank is installed at ground level. This is provided with an apron to collect rain water. Stream bank should be in suitable slope to facilitate animal movement but it should not promote erosion. Dug outs: these are small excavations for the collection of rain water. Other measures: these include planting of trees in upland, fire protection, distribution of water holes, etc. All these measures improve the water infiltrations; reduce runoff and ground water recharge. 3. Cover or shelter improvement: Shelters refers to the Quality and Quantity of the arrangement of essential needs for the existence of an animal. It describes the continuity of shelter for animal requirement. Shelter can be improved using the following measures: i. Protective cover: It helps the animals to escape from enemies and also from adverse weather factors such as extreme temperature of cold and heat. It includes: Hedgerows: It refers to planting of low woody vegetation along fence rows in river and pond banks. Brush Piles: These are loose heaps of small trees, woods, shrubs, cut logs, and old fence. This protection depends upon mobility of the animals and proximity to water bodies. Natural/Artificial roosts: These are made for the animals and are facilitated by planting of trees.
ii. Nesting Cover: These are made inside the forest areas by placing artificial nests suitable to animal’s requirements. Ground Nesting Covers: It is provided to give an adequate, permanent and undisturbed cover. This is achieved by regulating planting, grazing and protective measures. Den and Nesting Trees: Trees of 5-10 Years are retained for encouraging nesting of birds and animals. Trees with existing nests are conserved and periodically monitored. Nest Boxes: These are artificial and should be light and durable. The design should vary with animal’s requirements.
4. Wetland Improvement: It can be achieved by the following measures: Existing structures are improved Water management practices are to be carried out. This should consider topography, soil and climate. Existing succession is assessed so that it is not disturbed. Shallow marshes should be improved by artificial flooding, ditching, and dredging
5. Predation Management and control: This is an extensive task which considers many parameters and relationships. It can be achieved by way of following measures: First, food cycle and ecological triangle in the specific ecosystem is studied well Then, the predator and prey population is regulated
6. Tourism Improvement: It is achieved by the following means: Education and training is to be imparted to optimize people’s enjoyment Impact of the tourism is minimized through suitable tourism management Increase the awareness about the conservation. INJURIES CAUSED BY PEST AND DISEASES
Pest and diseases causes extensive damage to forest Vegetation. The following are some of the common pests observed in forests:
Pests of some Important tree crops
S.no Pest Zoological Name Symptom Teak Skeletonization of the older leaves and 1 Teak defoliator Hyblaea purea defoliation 2 Teak Skeletonizer Eutectona macheralis Skeletonization of the leaf uniformly 3 Leaf Roller Syllepta straminea Rolling of tough and hard leaves 4 Shoot Borer Nodostoma bhamoense Holes on tender shoot Bamboo 1 Internode Borer Estigmena Chinensis Boring and tunnelling of internode 2 Borer Cyrtotrachelus dux Boring Young sprouting clumps 3 Leaf minor Cosmopteryx bambusae Leaf mining and rolling Neem 1 Shooot borer Pulvinaria maxima Infects the shoot and Stem 2 Thrips Taeniothrips chatogastra Infests flower and Leave 3 Seed Borer Aracerus Faciculatus Seeds Bored by the grub beetle Eucalyptus Odontotermes sp. 1 Termites Causes ring barking of the root Microtermes sp. 2 Feeder Celosterna scabrator Feeding of the tender shoots by larva 3 Grindler Batocera rufomaculata Grindle the shoots by larva Sandal Wood 1 Leaf Webber Cacoecia micacaena Leaves webbed together by larva 2 Defoliator Latana Inflata Defoliation by nymph and adult 3 Aphids Jassus Indicus Vector of spike disease 4 Thrips Crotonothirips davidi Galls on leave by nymph and adult Casuarina Needles of casuarinas bored by the larva, 1 Borer Eumenodera tetrachorda leaving the epidermis intact by the larva Wilting of branches or plants, presence of 2 Red Borer Zeuzera coffeae bore holes plugged with excreta at the base of the plant 3 Indarbella Quadrinototo Leaves with circular holes and defoliation Diseases of some important Tree Crops
S.no Disease Causal organism Symtom Teak Minue white patch on the surface of Leaves 1 Powdery mildew Uncinula tectonae Powdery growth turns to light brown patches Upper leaf surface dull green in colour and necrotic appear as brown spots Lower leaf surface orange or yellow in 2 Rust Olivea Tectonae colour Severe infection on nurseries and young plantations Minute dark brown dots 2-3 mm in diameter and enlarge to 5-8 mm in 3 Leaf Spot Phomopsis Tectonae diameter Concentric rings around the light coloured center spot Complete drying of lamina of the Leaves 4 Leaf Spot Alternaria alternate Presece of concentric rings in the bighted area Bamboo Minute spindle shape appear on the Leaf surface Turn dark brown to dull violet and 1 Leaf Spot Bipolaris bambusae grayish brown center Lension coalesces to form larger necrotic areas Minute spindle shape appear on the margin of the leaf blade 2 Leaf Blight Helminthosporium turcicum Major portion of the leaf giving a blighted appearance Brown water soaked leisson on major protion of the leaf and complete frying 3 Leaf Blight Alternaria Alternata of the lamina Presence of the concentric rings on the blighted area Neem The pathogen is soil borne and infect leaves of young seedlings 1 Web blight Rhizoctonia solani Grayish brown affects on entire leaf area Minute Gray spots with dark margins 2 Leaf Spot Cercospora meliae Thin and papery leaves drops off leaving shot hole symptoms Yellowing and droping of leaves in one or two branches of the trees , subsequently folllwed by drying of the 3 Root rot Gnoderma Lucidum branches The fungus grows extensively from the bark and causes white rot of the sap wood which becomes spongy Eucalyptus Minute black spots with dark margins The infection spread to young shoots 1 Leaf spot Collectotrichum eucalypti leading to death of the growing point and die back symptoms A brown soak is spread on the major portion of the leaf leading to complete 2 Leaf blight Alternaria alternate drying of the lamina Presence of concentric rings on the blighted area Minute black cankerous growth and 3 Stem Canker Diaporthe cubensis enlarge to major portion of the branch Drying of the infected branches Sandal wood Shortened intermodal length Leaves colour change sfro yellowish to red colour 1 Spike Phytoplasma Branches donot Flower The floral carts are modified into green leafy structures called Phylloides Partial parasite in stem It produce haustorial connections to 2 Flowering parasites Debdrophthoe falcate drive the food source 15-20 gall clusters Severe condition, branches become dry Casuarina Yellow discolouration spreads to major Leaf spot/ Needle 1 Phoma casurinae part of the needles Blight Needles turn to black color Yellowing and dropping of leaves in one or two branches of the trees 2 Root rot Ganoderma lucidum followed by the drying of the branches White rotting of the sap wood The infection occurs in nursery and very young plantations The infection spread to major portion of 3 Flowering parasite Cuscuta campestris the plant with complete to golden yellow colored threads of the parasite growth