Abstract

Objective

In this science fair project you'll use a homemade bug vacuum to collect insects from your backyard to determine whether it is a biologically diverse habitat.

Introduction

Have you ever heard the phrase "The more the merrier!"? In ecology—which is the study of living things and the habitats (or places) they live in—the phrase should be "The more species the healthier!". Habitats that have lots of biodiversity are considered healthy. Part of biodiversity is having many different types of plants and animals living in the same habitat. The plants and animals rely on one another for their entire life cycles. For example, let's say berries from a bush are eaten by a field mouse, then the mouse helps transport the seeds inside the berries to different locations, allowing more berry bushes to grow. The mice are eaten by birds of prey, like hawks, and then some of the hawk eggs get stolen and eaten by a fox, and on and on the chain goes. This web of relationships is called an ecosystem. The greater the biodiversity, the larger the ecosystem, and the healthier the habitat.

Click here to watch a video of this investigation, produced by DragonflyTV and presented by pbskidsgo.org

Wildlife biologists study and monitor the health of habitats and ecosystems. One way they do this is to survey (identify and count) populations of plants and animals to determine how much biodiversity is in a habitat. In this video from DragonflyTV, Ronnie and Denise help a wildlife biologist conduct a population survey of the fish in their local lake. If they find good-sized populations of several different species of fish, they'll know that their lake is a healthy habitat. How do you think they do it? Watch the video to find out what kind of biodiversity they observe, how they observe it, and what their findings mean about the lake!

From the video you can see that surveying populations of fish is hard work that requires a lot of equipment, like boats, nets, and containers to hold the fish. Plus, you have to live near a water habitat! Insects, on the other hand, are easy to find in many outdoor habitats, and catching them doesn't require much equipment. In this science fair project you'll do your own biodiversity survey right in your own backyard (or in a nearby park or field) by looking at how many species of insects you can find. To conduct your survey you'll build a simple bug vacuum to collect the insects. Get ready to suck those bugs up!

Terms, Concepts, and Questions to Start Background Research

• Ecology
• Habitat
• Biodiversity
• Ecosystem
• Wildlife biologist
• Species

Questions

• What do wildlife biologists do?
• How are population surveys conducted?
• What is biodiversity?
• What are some different kinds of habitats?
• What are some examples of different species of insects?

Bibliography

• TPT. (2006). Fish Population by Ronnie and Denise. DragonflyTV, Twin Cities Public Television. Retrieved June 25, 2008 from http://pbskids.org/dragonflytv/show/fishpopulation.html
• Pollock, M. (2007). Bug Pooter. RAFT: Resource Area for Teaching. Retrieved June 25, 2008 from http://www.raft.net/ideas/Bug%20Pooter.pdf

To find out more about insects, try these websites:

• BioKIDS. (2008). Critter Catalog: Insects. Retrieved June 26, 2008 from http://www.biokids.umich.edu/critters/Insecta/
• USDA. (2008). Northern Plains Agricultural Research Laboratory: Just for Kids! Retrieved June 26, 2008 from http://www.sidney.ars.usda.gov/sidebar/justforkids2.html

These websites are good resource about ecology and biodiversity:

• NCEAS. (2004). Kids Do Ecology. Retrieved June 26, 2008 from http://www.nceas.ucsb.edu/nceas-web/kids/index.html
• American Museum of Natural History. (n.d.). Biodiversity: Everything Counts! Retrieved June 26, 2008 from http://www.amnh.org/ology/?channel=biodiversity&c#

For help creating graphs try this website:

• National Center for Education Statistics (n.d.). Create a Graph. Retrieved June 26, 2008 from http://nces.ed.gov/nceskids/CreateAGraph/default.aspx

Materials and Equipment

• Plastic container with lid, 1-cup or ½-pint size (containers from the deli of your local grocery store work well)
• Single-hole punch or leather awl
• Flexible drinking straws (2); wider ones are better as they will allow larger insects to be caught.
• Tape
• Pen or pencil
• Nylon stocking
• Scissors
• Plastic wrap, clear
• Tape measure
• Sticks (4)
• String (17 feet)
• Optional: magnifying glass
• Lab notebook
• Graph paper

Experimental Procedure

Making the Bug Vacuum

1. With an adult's help, use a single-hole punch or a leather awl to make a hole in the side of the plastic container.
   1. The hole should be 1 centimeter (cm) below the top rim of the container.
2. Using the same technique, punch a second hole opposite the first one, again 1 cm below the top rim of the container.
3. Insert the mouth end of a flexible straw into one of the holes. See Figure 1 below.
   1. If the straw does not fit tightly into the hole, wrap tape around the straw to make the straw fatter. Put the straw back into the hole. Keep adding tape and reinserting the straw in the hole until the two fit together tightly.
   2. If the straw is too large for the hole, gently push a pen or pencil through the hole to widen it until the straw fits. Make sure the connection between the straw and the hole is snug.
4. Cover the mouth end of the second straw with a piece of nylon stocking. See Figure 1 below.
   1. Cut a piece out of the nylon stocking, large enough to be taped to the end of the straw.
   2. Use tape to secure the stocking piece to the straw.
   3. If necessary, overlap two layers of the stocking so that air can pass through but insects will not be able to.

   Figure 1. The two straws are inserted into the plastic container opposite one another. One of the straws is covered by a filter made from a piece of nylon stocking.

5. Using the same method as in step 3, insert the mouth of the covered flex straw from step 4 into the second hole in the plastic container.
6. With an adult's help, use a pair of scissors to cut out the center out of the plastic container's lid. This will be the observation window of the insect vacuum. See Figure 2 below.
   1. Fold the lid in half to easily cut out a circle.
   2. Leave a 1-cm border around the rim of the lid.

   Figure 2. Folding the lid in half makes it easier to cut a circle out of the plastic.

7. Stretch a piece of clear plastic wrap over the top of the plastic container. Hold the plastic wrap in place by snapping the lid of the container back on. See Figure 3 below.
   1. If you need to get rid of wrinkles, lift part of the lid and gently tug the plastic wrap to remove them, then snap the lid back in place.
   2. Make sure the plastic wrap is tight enough that the insect vacuum window is easy to see through.

   Figure 3. The completed insect vacuum is depicted here. Notice the clear plastic wrap window.

Collecting Insects

1. Mark off a 4-foot by 4-foot section of your yard, a field, or other outdoor place where you think insects might live. See Figure 4.
   1. Use a tape measure to measure a 4-foot line on the ground.
   2. Mark the beginning and end of the 4-foot line by pushing sticks into the ground so that they stand upright.
   3. Using the tape measure, place two more sticks parallel to the sticks already in the ground, 4 feet away. The result should be four sticks marking the corners of a 4-foot by 4-foot square.
   4. Tie string between the four sticks, low to the ground, to identify the perimeter of your testing square.

   Figure 4. A tape measure can be used to make a 4-foot by 4-foot square, with sticks and string marking the boundaries.

2. Carefully search the 4-foot by 4-foot testing square for insects. Use the insect vacuum to suck up all the insects you find, as described below. You'll need to have a search pattern so that you don't crush insects in the square.
   1. To begin collecting insects, start at one corner of your test square and walk along one edge of the square, walking on the outside of the string but looking into the square.
   2. When you find an insect, gently place the filter-less straw so that the end is very close to the insect.
   3. Place the straw with the nylon filter in your mouth and breathe in forcefully. This will create a vacuum, which sucks in the insect. Repeat this process until the insect has been transferred into the plastic container chamber.
   4. After you've walked along the outside of one edge, start walking in a zigzag pattern inside your test square. See Figure 5.
   5. Repeat your paths again until most of the insects in the 4-foot by 4-foot testing area have been collected.

   Figure 5. To avoid crushing the insects as you collect them, establish a zigzag search pattern, like the one shown here, walking on strips of ground where you've already collected bugs.

3. Examine the insects you collected by looking at them through the plastic wrap window of the insect vacuum.
   1. You may want to use a magnifying glass to get a better look at the insects. How many different types of insects did you collect?
   2. In your lab notebook, make a data table describing each type of insect you collected. Note down how many you collected of each type.
   3. Optional: Drawing a picture of each type of insect is an additional way in which you can describe the insects you collect.
   4. When you are done examining the insects, you should release them outdoors.
4. Repeat steps 1-3 on two additional days.

Insect Type	# Collected	Insect Descriptions: Day 1
		Color(s)	Number of Wings	Antenna (yes/no)	Picture
Type A
Type B
Type C

Analyzing the Data

1. Draw three bar graphs to illustrate your data—one for each day's data.
   1. Make a bar for each type of insect you collected.
   2. The height of the bar represents the number of individuals you collected for each type of insect. For example, if you collected four ants and two ladybugs on day 1, the graph for that day would show two bars. The bar representing the ants would be four squares high and the bar representing the ladybugs would be two squares high.
   3. You can make the graphs by hand or use a website like Create a Graph to make the graphs on the computer and print them.
2. How many types of insects did you collect? Which type was most common? Was your data similar on all three days? Based on your data, do you think there is a lot of insect biodiversity in the area you chose to test?

Variations

• What kinds of insects do you expect to find in your backyard? Research which species of insects live in your area. Then do the science fair project above, this time using insect guidebooks and websites to identify the insects you collect. Did your expectations match your results?
• Do different locations have different insects? Compare two or more different habitats, like a field and a forest. Which habitat has more insect biodiversity? Why?
• Does changing the conditions in your test area change the types of insects you collect? For example, what happens to the biodiversity if you sprinkle the ground with water first?

• For more science project ideas in this area of science, see Environmental Science Project Ideas.

Credits

Sandra Slutz, PhD, Science Buddies

This science project was inspired by this DragonflyTV Podcast:

• TPT. (2006). Fish Population by Ronnie and Denise. DragonflyTV, Twin Cities Public Television. Retrieved June 25, 2008 from http://pbskids.org/dragonflytv/show/fishpopulation.html
• The concept for the insect vacuum was adapted from: Pollock, M. (2007). Bug Pooter. RAFT: Resource Area for Teaching. Retrieved June 25, 2008 from http://www.raft.net/ideas/Bug 20Pooter.pdf

Last edit date: 2008-09-17 22:00:00