AIM
4/20/23
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1
Bird Hazards and Flight Over National Refuges, Parks, and Forests
Section 5. Bird Hazards and Flight Over National
Refuges, Parks, and Forests
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1. Migratory Bird Activity
a.
Bird strike risk increases because of bird migration during the months of March through April, and August
through November.
b.
The altitudes of migrating birds vary with winds aloft, weather fronts, terrain elevations, cloud conditions,
and other environmental variables. While over 90 percent of the reported bird strikes occur at or below 3,000
feet AGL, strikes at higher altitudes are common during migration. Ducks and geese are frequently observed up
to 7,000 feet AGL and pilots are cautioned to minimize en route flying at lower altitudes during migration.
c.
Considered the greatest potential hazard to aircraft because of their size, abundance, or habit of flying in
dense flocks are gulls, waterfowl, vultures, hawks, owls, egrets, blackbirds, and starlings. Four major migratory
flyways exist in the U.S. The Atlantic flyway parallels the Atlantic Coast. The Mississippi Flyway stretches from
Canada through the Great Lakes and follows the Mississippi River. The Central Flyway represents a broad area
east of the Rockies, stretching from Canada through Central America. The Pacific Flyway follows the west coast
and overflies major parts of Washington, Oregon, and California. There are also numerous smaller flyways which
cross these major north-south migratory routes.
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2. Reducing Bird Strike Risks
a.
The most serious strikes are those involving ingestion into an engine (turboprops and turbine jet engines)
or windshield strikes. These strikes can result in emergency situations requiring prompt action by the pilot.
b.
Engine ingestions may result in sudden loss of power or engine failure. Review engine out procedures,
especially when operating from airports with known bird hazards or when operating near high bird
concentrations.
c.
Windshield strikes have resulted in pilots experiencing confusion, disorientation, loss of communications,
and aircraft control problems. Pilots are encouraged to review their emergency procedures before flying in these
areas.
d.
When encountering birds en route, climb to avoid collision, because birds in flocks generally distribute
themselves downward, with lead birds being at the highest altitude.
e.
Avoid overflight of known areas of bird concentration and flying at low altitudes during bird migration.
Charted wildlife refuges and other natural areas contain unusually high local concentration of birds which may
create a hazard to aircraft.
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3. Reporting Bird Strikes
Pilots are urged to report any bird or other wildlife strike using FAA Form 5200
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7, Bird/Other Wildlife Strike
Report (Appendix 1). Additional forms are available at any FSS; at any FAA Regional Office or at
https://www.faa.gov/airports/airport_safety/wildlife/. The data derived from these reports are used to develop
standards to cope with this potential hazard to aircraft and for documentation of necessary habitat control on
airports.
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4. Reporting Bird and Other Wildlife Activities
If you observe birds or other animals on or near the runway, request airport management to disperse the wildlife
before taking off. Also contact the nearest FAA ARTCC, FSS, or tower (including non
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Federal towers) regarding
large flocks of birds and report the: