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The Frontiers Decade:
Environment Decade

Tracking bluefin tuna in the Mediterranean, building nests for homeless woodpeckers in North Carolina, aiding migrating storks in the Middle East and restoring black-footed ferrets to the American West are just a few of the animal conservation programs seen on Frontiers. Reintroduction programs and genetics advances may preserve some of our most endangered species.


Many animal species are very sensitive to the presence of humans. People compete for resources like food and territory; they also disrupt breeding and other animal behaviors. In this activity, you'll observe different species to see how sensitive they are to human presence. Birds are good study organisms. They're easy to spot, and you should be able to find several species nearby. If you prefer, modify this activity to apply to other animals -- snakes, insects or spiders, for example.


  • bird food (seeds, bread crumbs, sunflower hearts, suet, etc.)
  • binoculars (optional)
  • field notebook

Work with a partner in this activity.

  1. Divide into teams. Each team will be responsible for observing the behavior of different species of birds.

  2. Each team should select one species easily found near your school. Depending on the number of species around, teams may need to observe the same species.

  3. Find an area where you can easily hide without being seen by the organism you are observing. (For long-term study, you might want to build an observation blind that lets you slip in and out without being seen by your subject.)

  4. While hidden, spend about 15 minutes observing in the field. Write down your observations. Take notes on location, time and date, weather, bird or animal behavior. Repeat your observations over several days. Try to minimize variables that may affect behavior of the organisms. For example, try to observe at the same time of day, don't make any noise, etc.

  5. After you complete your initial observations, predict how you think the birds might change their behavior if you introduce extra food into their environment.

  6. Test your prediction by placing the food in an easily accessible place near your observation site. Be careful to place the food so you aren't exposed to the birds for a long period of time.

  7. Repeat steps 3 and 4, taking care to notice any differences in behavior from your earlier notes.

  8. After several days of recording observations of the birds feeding, see what happens if you place the food and sit outside your observation site. Be careful to sit quietly and try to minimize movement. You want to be clearly visible, but not overly distracting.


  1. How did the birds' behavior vary over the course of your observations?

  2. Did your observations produce evidence that your presence distracted the birds so much they changed their behavior?

  3. How did the birds react to the presence of more food? Can you cite instances in nature where human presence has a positive effect on the organisms in an area?

  4. Compare observations of the different species observed. Were some birds more sensitive to human presence than others? Support your conclusion with specifics from your journal.

  5. Why do you think some animals are more sensitive to human presence than others?

  6. Were you able to observe certain species' preferences for different foods?


  1. Investigate the impact of development in your community on local species.

  2. If possible, find out what species native to your region have disappeared in the last 100 years or so.

  3. The National Audubon Society and the Cornell Lab of Ornithology sponsor bird count surveys during the year. Visit to find out more about the surveys and birding. Look for information here about Classroom FeederWatch, a program for schools to participate in bird surveys, compare data with other schools over the Internet and chat with scientists.


Episodes on Frontiers featuring animals in zoos or wildlife parks include Science Safari (Show 602), The New Zoos (Show 805) and Voyage to the Galápagos (Show 1001). Stories about endangered species and reintroduction programs include "Homeless Woodpeckers" in Show 205, "Rescuing the Black-Footed Ferret" in Show 305, "Dams and Dolphins" in Dragon Science (Show 602), "Turtle Travels" in Science in Paradise (Show 901) and "Turtle Hospital" and "The Sea Within the Sea" in Mediterranean on the Rocks (Show 1004). Please visit the Subject-Area Search feature on this website for more information about these Frontiers shows and related activities!


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
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