© 2009 Delmar, Cengage Learning Chapter 9 Wildlife Biology and Management

© 2009 Delmar, Cengage Learning

Chapter 9

Wildlife Biology and Management


Study of Life

• Biology is the study of life– Botany seeks to understand the life of plants– Zoology is the study of animal life


Study of Life

• Zoologists study the basic needs of animals– Food, water, shelter, and space

• These basic needs are of equal importance

• Suitable wildlife habitat requires a balance of these requirements


Animal Behaviors and Habits

• Life is the product of distinct behaviors and habits that help an organism meet basic needs– Way in which organism meets basic needs is

often distinctive to it


Animal Behaviors and Habits

• Behavior is both learned and instinctive– instinctive: evident at birth– learned: behavior picked up through life

experiences


Life Requires Energy

• Food– Anything organism consumes to get energy– Amount of food required depends on age, sex,

size, location, season of year


Life Requires Energy

• Differences exist in ways organisms obtain nutrients– different preferred foods– different digestive systems

• simple stomach, multiple stomachs, gizzard, etc.


Food Sources

• Organisms differ in types of foods consumed– Herbivores: Obtain food directly from plants– Carnivores: Consume other animals

• also called predators

– Omnivores: Consume both plants and other animals


Water

• Organisms differ in their relationship to a necessary resource: water– Some require standing water

– Some drink water

– Others get water from food they eat

– Still others absorb water from the environment

– Aquatic organisms actually live in water


Shelter

• All organisms have basic habitat needs– Habitat: Home where organism eats, rests, and

reproduces

– Must provide an organism’s basic needs

• Suitable habitat provides adequate shelter– protection from weather, predators

– places to reproduce


Shelter

• Shelter can take many forms– often a form of vegetation or vegetative cover

– can be pile of rocks, hole, cliff overhang, etc.


Space

• All organisms have a home range– Area within which they live and obtain resources

– Size of home range varies

– Tolerance of others’ presence varies


Space

• In any habitat, animals must not be overcrowded– Overcrowding can result in stress, disease, damaged

habitat


Arrangement of Basic Needs

• All wildlife requires– food– water– cover– space

• Habitat containing these basic requirements will support life


Arrangement of Basic Needs

• Optimal populations achieved when basic needs are appropriately arranged– What if primary food supply is across a four-

lane highway?


Wildlife Relationships

• Many organisms participate in many types of relationships– parasitism

– mutualism

– predation

– commensalism

– competition


Parasitism

• Relationship between two organisms in which one feeds on the other without killing it– May be plants or animals– Parasites may be either internal or external


Parasitism

• Example of a parasitic relationship– wood tick

• lives on almost any species of warm-blooded animal


Mutualism

• Two types of animals living together for their mutual benefit

• Example: tick pickers– birds remove and eat ticks from many African animals

• Wild animals have parasites removed from them

• Birds receive nourishment from ticks


Predation

• Situation in which one animal eats another– predator: does the eating

– prey: gets eaten

• Predators are often critical in controlling wildlife populations


Predation

• Populations of predators and prey tend to fluctuate widely– When predators are in abundance, prey becomes scarce

because of overfeeding

– When prey becomes scarce, predators may starve or move to other areas


Commensalism

• Situation in which plant or animal that lives in, on, or with another but does not help or harm it

• Example– vultures waiting to feed on leftovers from a cougar’s

kill


Competition

• When organisms contend for same food supply, cover, nesting sites, or breeding sites– Competition may exist among members of same

species or between or among different species


Competition

• Competition often results in changes in population levels– One species may increase in number whereas the others

decline

– Often the numbers of both species decrease


Preserving Wildlife

• Various efforts have been made to protect wildlife

• U.S. Endangered Species Act– passed to protect at-risk animal species and their

habitats


Preserving Wildlife

• U.S. Endangered Species Act– identifies two classes of at-risk species

• endangered: immediate danger of extinction

• threatened: at risk of becoming endangered

– Strategies include transplanting organisms, hatcheries, breeding programs


Human Impacts on Wildlife

• Humans impact wildlife in many ways– Habitat destruction is the single greatest threat facing

wildlife

• Habitat destruction occurs as a result of many human activities– Construction, farming, mining, timber harvesting, and

pollution


Stewardship

• Wildlife and other natural resources should be managed with a long-term view and commitment to the resources– Will require knowledge of proven management

practices and ecology and habitat requirements


Stewardship

• Wise stewardship occurs when managers of natural resources make management decisions based on dependable information


Extinction

• Extinction of species is serious concern

• Several factors contribute to extinction– introduction of alien species that outcompete native

species

– overhunting by humans

– lack of adaptability in a species

– slow rate of reproduction


Extinction

• Destruction or modification of habitat– single greatest cause of extinction


Managing At-Risk Species

• Managing populations of endangered or threatened species is difficult– Effective management of endangered species must be

based on reliable research

• Managing at-risk species will involve providing acceptable shelter and food sources


Managing At-Risk Species

• Management decisions must be applied in a variety of habitats– farms, forests, wetlands, streams, lakes, and ponds


Managing Farmlands

• Management of farm wildlife often involves providing suitable habitat– usually by-product of farming or ranching practices


Managing Farmlands

• Farmland management techniques include– leaving corners of fields unharvested

– leaving shrubs and brush piles

– leaving crop residue standing through winter

– planting crops attractive to wildlife

– harvesting farm and ranch wildlife by hunting


Managing Forests

• Managing forests often focuses on increasing populations of a certain species– If species is present, the goal is to maintain its

population


Managing Forests

• Management of forests often involves– developing a forest-management plan

– making clearings to provide new growth

– selective harvesting to produce a variety of habitats

– leaving piles of brush for cover


Managing Forests

• Developing a forest-management plan– taking an inventory of species

– goal setting for habitat and species within it

– deciding how to support desired species


Managing Wetlands

• Most important habitat to wildlife– provide food, nesting sites, and cover for many species

of wildlife

• Wetland management techniques include– impounding or holding water

– cutting trees to open up wetland area

– leaving hollow trees for nesting


Managing Wetlands

– establishing open, grassy areas around wetlands

– planting vegetation for food and cover

– protecting from pollution

– providing artificial nesting areas

– breeding and release programs


Managing Streams

• Protecting existing is critical because we cannot build new streams

• Stream management plans usually focus on fish

• Management of streams often involves– preventing overgrazing of stream banks

– limiting access to stream by livestock


Managing Streams

– maintaining streamside vegetation

– sustaining desirable species of wildlife

– balancing populations with food supply

– using hatchery and stocking programs

– regulating sport fishing


Managing Lakes and Ponds

• Management techniques similar to streams

• Several management practices unique to standing water– controlling pollution

– sustaining desired mixtures of species


Managing Lakes and Ponds

– maintaining appropriate dissolved oxygen levels

– eliminating unwanted species

– stocking desired species

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© 2009 Delmar, Cengage Learning Chapter 9 Wildlife Biology and Management