Goals for the Lesson
- Students will understand what a habitat is and be able to describe its four elements.
- Students will see how an area's habitat suitability varies with different species of wildlife.
- Students will be able to name factors that affect habitat suitability.
- copies of the class outline for each student
- board or overhead
State Standards Addressed: E & E Standards: Renewable and Nonrenewable Resources (4.2); Ecosystems and Their Interactions (4.6)
Subjects Covered: environmental science, biology
Topics Covered: wildlife habitat, ecology, habitat improvement
- Read through the lesson thoroughly and be able to answer the students' questions about the habitat of local wildlife. You may also want to think about showing your class actual habitat and allow them to come up with the wildlife most likely to be present in that area if this is available.
"What is the term used to describe where an animal lives? It is called a 'habitat' and it can be defined as the kind of place where an animal, bird, fish, or plant lives in a natural state. Today we a going to look at the elements that make up an animal's habitat and how they relate to the animals that live there. We will also look at why some habitats suit some animals and not others."
- After defining "habitat," you may want to relate that to the students' habitat or where they live. Point out that their habitats differ and also that their habitat preference may differ as you will find out if you ask them. Make sure they understand the concept.
- Explain that the four elements of habitat are cover, food, water, and space. Cover usually refers to just what it sounds like--something to cover the animal. These include, but may not be limited to, breeding area, nesting site, hiding place, resting place, safe place to sleep, feeding area, and travel route. Cover may be provided by vegetation or rock outcroppings or, sometimes, by old abandoned buildings in the middle of the forest. Cover is a must, as is the other elements. If the other three elements exist without cover, the animal won't thrive.
- All animals must eat just as we do. Therefore, sufficient food must be available for a species to thrive. This includes one type for herbivores and another for carnivores that must be present. Sometimes we humans provide food for wildlife. This, however, can backfire if we make animals, such as deer, dependant on this food source. We can also elevate a population to a dangerous level and cause other problems.
- Water, too is needed for animals to survive. Many animals are dependant on streams or intermittent water holes. Many times we can improve these water sources without impacting the size of a population or causing negative consequences. Watering holes are also excellent places to observe wildlife.
- Space is the fourth element of habitat. Species of wildlife vary widely in the amount of space they need to live. The range of a rabbit is much different from that of a black bear or a gray fox. The abundance of the other three elements may also impact the amount of space needed by an animal. The more concentrated the food, water, and cover, the less total space an animal may need.
In addition to these elements merely existing, they must also be:
- available in adequate amounts.
- high enough quality to meet the needs of animals
- distributed where animals need them
- This, in turn, affects the carrying capacity of an area. Carrying capacity refers to the number of animals a habitat can support over a given period of time. The larger the abundance of the four elements of habitat, the larger the carrying capacity of an area. This can be related to people and how many houses can be built in a given area.
- Habitat suitability is described on the worksheet. What makes a given habitat suitable for a particular animal? We already know that different animals need different types of habitat. What can we look at to see if it suits various animals?
- "Plant succession" is the process that occurs when one plant community replaces another over time. A grassy field will grow shrubs, then small trees, and taller trees, and these will eventually shade out the smaller trees and shrubs. The whole process takes decades and can be set back to any point from a disturbance. Different species like different stages of succession. Some like a shrubby forest, as do deer. Some songbirds require a mature forest with tall mature trees.
- The vertical structure refers to how plants are layered in a forest. The three layers include the ground layer, shrub layer, and the canopy layer. Different types of wildlife require and live in different layers.
- Edge is the boundary where two types of vegetation meet. An example is the boundary between a hay field and a forest. These areas attract many types of wildlife because of the variety of food and cover. However, sometimes we can create too much edge by breaking up larger expansive areas some animals need.
- Some species also require more than one type of habitat. They may need one type for nesting and another type to feed in. Obviously these two types need to be close together. Having mixed plots of different successional stages in an area is called interspersion. An example of this would be having cornfields, mature forests, and shrubby woods all in the same area.
- Fragmentation is caused when we break up large areas of habitat by developments, roads, and agriculture. While on a small scale, this sometimes can just cause interspersion, more of it can lead to less food and cover for animals. It can also cause dangerous circumstances for animals from roads as well as disrupt the food chain.
- The presence or absence of corridors also can impact habitat suitability. Corridors are areas of secure cover that permit animals to travel from one patch of habitat to another. Without them, some animals wouldn't use some areas because they wouldn't feel safe traveling between them.
- Since different species of animals require different types of habitat, it is difficult to manage a forested area for all kinds of wildlife. We all want to see all kinds of wildlife in the same area, but the fact of the matter is that sometimes it is not possible. Likewise, managing for both timber and wildlife can be difficult.
- A landowner must decide what benefits are to be stressed the most. What type of wildlife is most important? What timber do you want to harvest? Which of the two is more important? However, don't set goals too narrowly. Make some compromises and you can enjoy many types of wildlife as well as economic benefits of timber.
- Have the students, either individually or in groups, choose a type of wildlife found in your area and research its habitat requirements. Tell them to include an example local area that is well suited to that animal. Have them turn in a short written report or do an oral report for the class.
- Written exam.
"Understanding Wildlife Habitat." Lesson plan NR036. Stewart-Peterson, Inc.
Williams, Lisa M., Margaret C. Brittingham, Sanford S. Smith (2001). The Wildlife Ecologist. University Park, Pa.: The Pennsylvania State University.
James I. Over, Northern Bedford High School/Agriculture