Wildlife Services

Protecting People 

Protecting Agriculture 

Protecting Wildlife

National Wildlife Research Center

FY 2017

Reducing Wildlife Hazards to Aircraft and Other

Vehicles

Contact Information:

Dr. Travis L. DeVault 

Supervisory Research Wildlife Biologist 

Ohio Field Station 

6100 Columbus Avenue Sandusky, OH 

44870 

Phone: (419) 625-0242 

FAX: (419) 625-8465 

Email:

travis.l.devault@aphis.usda.gov 

Website: www.aphis.usda.gov/

wildlifedamage/nwrc/ 

Groups Affected:

Airline passengers, pilots, crews,

owners and administrators

Aircraft and engine manufacturers

Civil airports

Insurance underwriters

Military pilots and aircrews

Residents near airports

Major Cooperators:

Airline Pilots Association

Airports across the United States

Bird Strike Committee USA

Federal Aviation Administration

Indiana State University

Mississippi State University

Michigan State University

National Association of State

Aviation Officials

North Carolina Division of Aviation

Port Authority of New York and

New Jersey

Purdue University

U.S. Air Force

U.S. Air Force Bird Air Strike

Hazard (BASH) Team at Kirtland

Air Force Base

U.S. Army

U.S. Fish and Wildlife Service

U.S. Marine Corps

U.S. Navy

University of Georgia

University of Illinois-Springfield

National Wildlife Research Center Scientists Study Wildlife Hazards On and Near Airports

Wildlife Services' (WS) National Wildlife Research Center (NWRC) is the only Federal research

organization devoted exclusively to resolving conflicts between people and wildlife through the

development of effective, selective, and socially responsible methods, tools, and techniques. The

NWRC field station in Sandusky, Ohio, is dedicated to providing a scientific foundation for WS and

Federal Aviation Administration (FAA) programs that reduce wildlife collisions with aircraft.

Consequently, the scientists work closely with WS airport programs throughout the nation, the FAA,

and the U.S. Department of Defense. 

To be certified for commercial passenger traffic by the FAA, many U.S. airports are required to develop

and implement a wildlife hazard management plan. The FAA strongly discourages any management

practice that might create wildlife hazards at airports. NWRC scientists conduct research to provide

guidance to the FAA, WS, and the general public regarding mitigation of wildlife-aircraft strike hazards.

More specifically, NWRC research is focused on understanding the nature of wildlife hazards on and

near airports; developing management methods and tools to reduce those hazards; and providing WS,

airport personnel, and the FAA with information on the latest strategies for controlling wildlife hazards.

Applying Science and Expertise to Wildlife Challenges

Changes to Aircraft Lighting to Increase Bird Awareness. — Collisions between birds and aircraft

(also known as bird strikes) are expensive, risk human lives, and increase bird mortality. Because birds

see differently than people, changes to aircraft lighting systems have been proposed as a way to make

birds avoid aircraft. NWRC researchers and partners from Purdue University investigated brownheaded cowbirds' responses to aircraft lighting systems tuned to match the birds' visual capabilities. 

Using a radio-controlled aircraft fitted with non-pulsing 470-nanometer lights (lights that falls within the

'blue' portion of the visible spectrum), scientists observed an increase in cowbird alertness. Cowbirds

showed alert behaviors twice as fast to radio-controlled aircraft with lights turned on versus those with

lights turned off. Researchers also observed that high ambient noise levels delayed the birds'

avoidance of the aircraft, possibly by causing sensory overload and distracting the birds. Researchers

concluded that use of 470-nanometer lights on aircraft might improve some birds' abilities to detect and

avoid aircraft. Such lighting systems may also make wind turbines, towers, and other large stationary

structures more detectable to birds. Additional studies have focused on identifying which wavelengths of 

light are most detectable to birds, as well as when lighting systems should be activated during

aircraft flights.

Chemical Control for Invasive Earthworms. — Though gardeners and fishermen love them,

earthworms can be a problem for airport managers trying to prevent bird strikes. Earthworms are food

for many birds, including gulls and European starlings, which can be a hazard to aircraft. For example,

after a rainstorm at Calgary International Airport in 2004, two aircraft struck gulls that were feeding on

earthworms and sustained damage during takeoff. Currently, no toxicants or repellents are registered

for earthworm control in the United States. In a series of laboratory and field studies, biologists at

NWRC's Ohio field station confirmed that tea-seed cake pellets (TSP), a byproduct of tea oil, caused

earthworms to come to the surface and dry up, temporarily reducing two non-native earthworm

populations. TSP contains triterpene saponins (natural detergents used in soaps) that irritate

earthworms' mucus membranes. Researchers also studied the impact of the repellent on ring-billed

gulls and saw no adverse effects to birds that fed on TSP-killed earthworms. Although effective, TSP

may need to be applied several times a year to ensure continued control.

Collisions Between Aircraft and Large Animals. — Because of their large size, animals such as

eagles and coyotes can cause significant damage to aircraft and pose a risk to aircraft passengers and

crew. Recently, NWRC scientists reported on large animal-aircraft collision trends and patterns. Of the

234 eagle collisions with civil and military aircraft reported to the FAA, U.S. Air Force, and U.S. Navy

from 1990 to 2013, 52 percent caused aircraft damage. During this 23-year period, bald eagle-aircraft

United States Department of Agriculture 

Animal and Plant Health Inspection Service
The U.S. Department of Agriculture is an equal opportunity employment provider and employer

collisions increased by 2,200 percent, and golden eagle-aircraft

collisions rose by 400 percent. During about the same time

period, more than 1,000 carnivore-aircraft incidents were

reported. Sixteen species were identified, with coyotes being the

most frequently struck species. Overall estimated carnivore

damage to aircraft from 1990 to 2012 was $7 million. Although the

incident rate for carnivores increased 13 percent per year, the rate

of damaging incidents remained fairly constant. Researchers

recommend increasing runway patrols at night from July through

November and maintaining high-perimeter fences to exclude

medium- and large-sized mammals. To help reduce eagle-aircraft

collisions, researchers recommend the use of non-lethal methods,

such as hazing, on airfields and the removal of food sources that

might attract eagles to airport environments.

Speed Kills: Ineffective Bird Responses to Oncoming

Vehicles. — How birds respond to approaching objects greatly

impacts their ability to detect predators, forage, flock, and avoid

collisions. Understanding variations in animals' visual capabilities

and other sensory systems may shed light on how they detect

and avoid threats from approaching aircraft, other vehicles, wind

turbines, and communication towers. To better understand birds' 

responses to approaching vehicles, NWRC researchers 

placed brown-headed cowbirds into a simulation chamber 

where they watched videos of vehicles approaching at 

various speeds. Researchers watched the birds' reactions to 

the videos and noticed that while they could successfully 

avoid slower moving vehicles, cars moving faster than 75 miles 

per hour overwhelmed the birds' escape strategies. Instead of 

adjusting their escape time to the car's speed, the birds only 

evaluated the distance between themselves and the vehicle. No 

matter how fast the car approached, the birds usually took off

when it was roughly 90 feet away. Helping birds overcome this 

apparent fixed avoidance distance threshold will enable 

researchers to develop aircraft and other vehicle lighting 

systems that will help birds respond to approaching 

objects sooner and avoid collisions.

Evaluation of Avian Radar to Prevent Bird Strikes. — The

Federal Aviation Administration and WS' Airport Wildlife Hazards

Program continue to look for better tools and methods for

preventing bird collisions with aircraft. One tool receiving

considerable attention is avian radar. These systems have the

potential to track bird activities on and near airports during the day

and night--providing real-time estimates of bird locations, altitude

and speed which could warn pilots and ground personnel of

potential wildlife hazards. To evaluate the ability of such systems

to detect and track free-flying raptors and waterbirds, NWRC and

Indiana State University researchers compared data gathered

from a Merlin Aircraft Birdstrike Avoidance Radar (DeTect, Inc.)

and field observers at the Terre Haute International Airport in

Indiana. Researchers focused initial studies on large species,

such as turkey vultures, red-tailed hawks, Canada geese and

sandhill cranes. A field observer would notify a radar operator

when a bird entered the study area and provide updates on the

bird's location every few seconds. The operator would confirm

whether or not the bird was being tracked by the radar. Such an

approach helped to identify instances when known birds were not

tracked by the radar system. Most of the large, single birds seen

by field observerswithin two nautical miles of the radar were

tracked by the radar about 30 percent of the time. Flocks of large

birds, even those that were located several nautical miles away,

were tracked by the radar about 40 to 80 percent of the time.

were tracked by the radar about 40 to 80 percent of the time. The

The results suggest that avian radar can be a useful tool 

for monitoring bird flock activity at airports, but less so for 

monitoring single, large birds such as raptors.

Selected Publications:

DeVault, T.L., B.F. Blackwell, T.W. Seamans, S.L. Lima, and E.

Fernandez-Juricic. 2015. Speed kills: ineffective avian escape

responses to oncoming vehicles. Proceedings of the Royal

Society B 282:20142188. doi: 10.1098/rspb.2014.2188. 

DeVault, T.L., B.F. Blackwell, T.W. Seamans, and J.L. Belant.

2016. Identification of off airport interspecific avian hazards to

aircraft. Journal of Wildlife Management 80(4):746-752. doi:

10.1002/jwmg.1041 

Doppler, M.S., B.F. Blackwell, T.L. DeVault, and E. FernandezJuricic. 2015. Cowbird responses to aircraft with lights tuned to

their eyes: Implications for bird-aircraft collisions. The Condor

117:165-177. doi:10.1650/CONDOR-14-157.1. 

Seamans, T.W., B.F. Blackwell, G.E. Bernhardt, and D.A. Potter.

2015. Assessing chemical control of earthworms at airports.

Wildlife Society Bulletin 39(2):434-442. doi: 10.1002/wsb.545. 

Sheridan, E., J. Randolet, T. L. DeVault, T. W. Seamans, B. F.

Blackwell, and E. Fernandez-Juricic. 2015. The effects of radar on

avian behaviour: implications for wildlife management at airports.

Applied Animal Behaviour Science 171:241-252. 

Washburn, B.E., M.J. Begier, and S.E. Wright. 2015. Collisions

between eagles and aircraft: An increasing problem in the airport

environment. Journal of Raptor Research 49(2):192-200. doi:

10.3356/rapt-49-02-192-200.1

Major Research Accomplishments:

WS research discovered that placing 470-nanometer lights on

aircraft or at airports may improve some birds' abilities to detect

and avoid aircraft. The lights may also make wind turbines,

towers, and other large stationary structures more detectable to

birds.

WS research found tea-seed cake pellets may be an effective

control for use with invasive earthworms found on airports.

Earthworms are an attractive food source for many birds which

are considered hazardous to aircraft.

WS researchers reported on large animal-aircraft collision

trends and patterns from 1990-2003. During this 23-year period,

bald eagle-aircraft collisions increased by 2,200 percent, and

golden eagle-aircraft collisions rose by 400 percent. During about

the same time period, more than 1,000 carnivore-aircraft incidents

were reported.

WS studies to better understand birds' responses to

approaching vehicles, such as cars and airplanes, found that

birds could not avoid cars moving faster than 75 mph. Instead of

adjusting their escape time to the car's speed, the birds only

evaluated the distance between themselves and the vehicle.

WS research with avian radar suggest that the tool may be

useful for monitoring bird flock activity at airports, but less so for

monitoring single, large birds, such as raptors.

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