PROJECT 2 : Who’s Home?

Determining whether or not organisms other than birds live in birds’ nests

Suggested Entry Categories

• Environmental Science
• Microbiology
• Zoology

Purpose or Problem

The purpose is to determine if a bird’s nest is home to more organisms than just birds.

 

Overview

The Earth is teeming with life. Just think how many things are alive within 100 feet of where you are right now: worms in the ground, flowers, trees, grasses, an insect on a window screen, a microscopic mite on your
pillow, mold on a piece of bread left uncovered in the kitchen, perhaps even a family member in the next room. You may hear the peaceful singing of a bird building a nest outside your window.

Birds lack the carpentry skills of humans, and they obviously don’t have the use of arms or hands. Yet, they are quite capable of constructing nests that are structurally sufficient for the laying of eggs and raising their young.

Nature provides all the nest-building materials a bird needs: twigs, feathers, animal hair, straw, moss, leaves, pebbles, blades of grass, and even some items provided by humans—a piece of yarn, string, or paper. Because nest building materials come from nature, and life is abundant all around us, do you think other things are living in birds’ nests besides birds?

Hypothesis

Hypothesize that you can find other forms of life besides birds in a bird nest. 

Materials’ List

• Bird nest containing baby birds
• Desk lamp that uses a standard 60 to 75 watt incandescent bulb
• Large funnel
• Clear jar about the size of a drinking glass
• High-power hand lens (magnifying glass)
• Microscope
• Small plastic bag
• Ten petri dishes with agar

Procedure

Scout around the trees on your property or in your neighborhood and look for a bird’s nest with baby birds inside. The nest must be within reach or able to be easily and safely retrieved (you don’t want one that is 50 feet in a tree top).

Once you locate a suitable nest, watch it once or twice a day, waiting for the day when the last baby bird leaves the nest. Do not get too close or disturb the nest in any way. As soon as possible after you see all the
birds are gone and the nest is no longer used by the mother bird, carefully remove the nest and place it in a plastic bag.

Take the nest home (or to school), but do not take it inside your house, just in case it contains insects or microscopic life that would not be good to have inside your home. Set the nest on a picnic table, a portable card table, or on a workbench in a garage. To collect tiny insects that may be living in the nest, place a large-mouth funnel in a clear jar. Then, set the nest in the mouth of the funnel. Position a desk lamp over the top of the nest, but keep a space of several inches between the lamp’s bulb and the nest to prevent the nest from getting hot. The incandescent bulb in the desk lamp should be about 60 or 75 watts. The heat from the bulb may drive any insects down into the glass, as they try to escape the heat. Leave the bulb on for one hour, and then carefully examine the glass for anything that has been collected. During the time the light is on, do not leave it unattended. 

Watch that the nest is not becoming too hot (to avoid a fire hazard and  harming anything that may be living in the nest). Use a high-power magnifying glass to examine any material that falls into the jar. Attempt to identify the organisms using field guides and other reference materials.

Next, check for the presence of smaller organisms in the nest. Do this by taking ten pieces from different locations on the nest and wiping them several times on agar in petri dishes. Cover the petri dishes and place them in a warm, dark location. After two weeks, examine each petri dish under a microscope. Never open any of the petri dishes once they have been closed. Eventually, when the project is over, dispose of the petri dishes, continuing to keep them sealed shut.

Results

Write down the results of your experiment. Document all observations and data collected.

Conclusion

Come to a conclusion as to whether or not your hypothesis was correct.

Something More

1. Can you locate other similar nests in your area that would indicate they were built by the same species of bird? The mother bird, the structure of the nest, and the size and designs on the egg shells will help you identify the species of bird using the nest. A good book on birds will be necessary to help you identify the species. Then, run the same tests as you did previously. Are the same organisms found in these nests?
2. What else did you find in the nest: leftover food, a piece of egg shell?
3. What is the composition of the nest? Can you identify other materials used making the nest?
4. How are nests adapted for rain? How are they adapted to ward off attacks from other animals?