learning targets “i can…” -describe edge effects as the physical and biological conditions...

14
Learning Targets “I can…” -Describe edge effects as the physical and biological conditions that change the habitat such that the area on the border cannot support the same species as the interior of the habitat. -Analyze the effectiveness of a nature reserve by taking into account edge effects.

Upload: gervase-wilkinson

Post on 03-Jan-2016

214 views

Category:

Documents


1 download

TRANSCRIPT

Learning Targets“I can…”

-Describe edge effects as the physical and biological conditions that change the habitat such that the area on the border cannot support the same species as the interior of the habitat.-Analyze the effectiveness of a nature reserve by taking into account edge effects.

Life on the Edge

Effects of Edges on Habitat Fragments

What is an “edge” habitat?

• A place where two habitats meet• Typically edges refer to forest habitat meeting

prairie, pasture, or farmland• Traditionally, forest edges are excellent areas

for wildlife; thus, some nature reserves are deliberately created with lots of edges

What is an “edge” habitat?

• Scientists are now finding that the edges actually may not be as beneficial to wildlife as previously thought, especially for those species that prefer to live on the interior of the forest.

CHESTNUT-BACKEDCHICKADEE

Edge Effects

• The edge of a habitat is exposed to very different physical characteristics than the interior.

THE EDGE OF THIS RAIN FOREST WILL

BE HOTTER AND DRIERTHAN THE INTERIOR

Edge Effects

• The edges of habitats are also affected by species that invade from the neighboring habitat.

Edge Effects

• Edge effects are defined as the physical and biological conditions that change the habitat such that the area on the border cannot support the same species as the interior of the habitat.

Edge Species

• Species that prefer the edge of two habitats have the best of both worlds; we call these organisms edge species.Example White-tailed Deer

They need the forest for cover but the meadow for grazing

Interior Species

• Plants and animals that are adapted to living in the middle of the forest and might not be able to survive at the edge are called interior species.

Designing a Nature Reserve

• A reserve that aims to preserve a species must consider whether or not the species prefers the edge or the interior.

What you will do today…

• Measure edge effects between Lowry Woods and the soccer fields

Study Questions

1. Complete the four graphs using the data you collected yesterday.

2. What did your results tell you about how habitats affect neighboring habitats?

3. Did you find the same plants and animals in Sites 1 and 5?

Study Questions

4. Below are the outlines of two different habitat islands. Which habitat island has the most interior habitat? Which habitat island has the most edge habitat?

Study Questions

5. Below is a view from above a forest habitat patch that was once continuous but now is cut in half by an eight lane super-highway. Assume that both halves of the forest contain the same species.

a. How will this highway affect the total number of species in the forest?

b. Which do you think will be more affected by the habitat fragmentation: birds or mammals? Why?