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Flight response of geese to helicopter traffic. Offshore oil drilling near an Alaskan estuary has led to increased air traffic—mostly large helicopters—in the area. The U.S. Fish and Wildlife Service commissioned a study to investigate the impact these helicopters have on the flocks of Pacific brant geese that inhabit the estuary in fall before migrating (Statistical Case Studies: A Collaboration between Academe and Industry, 1998). Two large helicopters were flown repeatedly over the estuary at different altitudes and lateral distances from the flock. The flight responses of the geese (recorded as “low” or “high”), altitude (hundreds of meters), and lateral distance (hundreds of meters) for each of the 464 helicopter overflights were recorded and are saved in the file. (The data for the first 10 overflights are shown in the table below.)

a. The researchers categorized altitude as follows: less than 300 meters; 300–600 meters; and 600 or more meters; Summarize the data in the file by creating a contingency table for altitude category and flight response.

b. Conduct a test to determine if flight response of the geese depends on altitude of the helicopter. Test using a = .01.

c. The researchers categorized lateral distance as follows: less than 1,000 meters; 1,000–2,000 meters; 2,000–3,000 meters; and 3,000 or more meters. Summarize the data in the file by creating a contingency table for lateral distance category and flight response.

d. Conduct a test to determine if flight response of the geese depends on lateral distance of the helicopter from the flock. Test using a = .01.

e. The current Federal Aviation Authority (FAA) minimum altitude standard for flying over the estuary is 2,000 feet (approximately 610 meters). Based on the results, parts a–d, what changes to the FAA regulations do you recommend to minimize the effects to Pacific brant geese?