For Public Distribution

Protecting the Flying Public and Minimizing Economic 

Losses within the Aviation Industry

Assistance provided by USDA-Wildlife Services to reduce 

Wildlife Hazards to Aviation

Fiscal Year 2020

Wildlife biologists and technicians with the USDA-Wildlife Services Program provided 299 staff 

years of assistance at 776 civil airports and military airbases in FY 2020 to reduce wildlife hazards 

to aviation. Activities included a broad range of technical assistance (e.g., training of airport 

personnel, monitoring wildlife populations) and direct management activities (e.g., wildlife 

dispersal, habitat modification). Program personnel, particularly at civil airports encountered

parked aircraft and reduced aviation traffic owing to the COVID-19 pandemic. 

Compiled by

Michael J. Begier, National Coordinator, Airport Wildlife Hazards Program, U.S. Department of 

Agriculture, Wildlife Services, Washington, DC 20250-3402 USA (mike.begier@usda.gov)

Richard A. Dolbeer, PhD, Science Adviser, Airport Wildlife Hazards Program, U.S. Department of 

Agriculture, Wildlife Services, 6100 Columbus Avenue, Sandusky, OH 44870 USA 

(richard.dolbeer@usda.gov)

Jenny E. Washburn, Airport Wildlife Hazards Program, U.S. Department of Agriculture, Wildlife 

Services, 6100 Columbus Avenue, Sandusky, OH 44870 USA (jenny.e.washburn@usda.gov)

February 2021
For Public Distribution

1

Protecting the Flying Public and Minimizing Economic Losses within the 

Aviation Industry

Assistance provided and Cooperator Funding received by USDA-Wildlife Services to 

reduce Wildlife Hazards to Aviation in FY 2020

Michael J. Begier, National Coordinator, Airport Wildlife Hazards Program, U.S. Department 

of Agriculture, Wildlife Services, Washington, DC 20250-3402 USA (mike.begier@usda.gov)

Richard A. Dolbeer, PhD, Science Adviser, Airport Wildlife Hazards Program, U.S. 

Department of Agriculture, Wildlife Services, 6100 Columbus Avenue, Sandusky, OH 44870 

USA (richard.dolbeer@usda.gov)

Jenny E. Washburn, Airport Wildlife Hazards Program, U.S. Department of Agriculture, 

Wildlife Services, 6100 Columbus Avenue, Sandusky, OH 44870 USA 

(jenny.e.washburn@usda.gov)

1. Why are aircraft collisions with wildlife a concern at airports? 

Aircraft collisions with birds and other wildlife (wildlife strikes) are an increasingly serious 

economic and safety problem (Marra et al. 2009). Dolbeer et al. (2021) estimated wildlife strikes 

(96% involving birds) cost the civil aviation industry in the USA a minimum of $196 million

annually, 1990-2019. Allan and Orosz (2001) estimated that bird strikes annually cost 

commercial air carriers over $1.2 billion worldwide, 1999-2000. Globally, bird and other wildlife 

strikes killed more than 293 people and destroyed over 272 aircraft from 1988 – 2020

(Richardson and West 2000, Thorpe 2012, Avisure 2021).

Efforts to reduce wildlife strikes need to focus on the airport environment because about 72% of 

all reported bird strikes with civil aircraft in USA occur at less than 500 feet above ground level 

(Dolbeer 2006, Dolbeer et al. 2021). Of the 59 large (maximum take-off weight >5,700 kg) 

turbine-powered aircraft (48 civil, 11 military) confirmed to have been destroyed because of bird 

or other wildlife strikes since 1960 worldwide, 56 (95%) of the strikes occurred during take-off 

or landing phases of flight at <500 feet AGL (Dolbeer 2008, Dolbeer, unpublished data).

2. Why is the wildlife-strike problem increasing?

Wildlife strikes have increased in the past 40 years because of a combination of factors. First, 

populations of many wildlife species that are hazardous to aviation have increased dramatically.

For example, the 36 species of birds in North America with mean body masses >2.5 lbs and at 

least 20 strikes with civil aircraft, 1990-2018 showed a combined population increase from 55 

million in 1990 to 89 million in 2018, a net gain of 34 million birds (Dolbeer 2020). These 

species include Canada and snow geese, white and brown pelicans, turkey and black vultures,

sandhill cranes, wild turkeys, bald eagles, great blue herons, double-crested cormorants, ospreys,

and red-tailed hawks. The white-tailed deer population increased from about 15 million in 1984 

to over 28 million by 2010 (McCabe and McCabe 1997, VerCauteren et al. 2011). Furthermore, 

most of these species have adapted to living in urban environments, including airports (e.g., 

Smith et al. 1999; Rutledge et al. 2015). 

A second factor relates to aircraft and engine design. Commercial air carriers have replaced their 

older three or four-engine aircraft fleets with more efficient and quieter, two-engine aircraft. In 
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1965, about 94 percent of the 1,037 turbine-powered commercial transport aircraft in the USA 

had three or four engines compared to less than 4 percent of the 7,381 aircraft in 2019 (U.S. 

Department of Transportation 2021, Aeroweb 2021). With the steady advances in technology 

over the past several decades, today’s two-engine aircraft are more powerful and reliable than 

yesterday’s three and four-engine aircraft. However, in the event of multiple-engine ingestions, 

especially with large birds such as geese, aircraft with two engines may have vulnerabilities not 

shared by their three or four engine-equipped counterparts (Langston 2019). A third factor is that 

birds are less able to detect and avoid the quieter two-engine, turbofan-powered aircraft in use 

today compared to older, noisier aircraft (Burger 1983, Kelly et al. 2001).

3. Can airport authorities and managers be held liable for wildlife strikes?

Based on a summary of cases by MacKinnon et al. (2001), Dale (2009), and Dolbeer (2018) and 

legal reviews by Michael (1986), Wilkinson (1998), Matijaca (2001, 2005), and Rillstone and 

Dineen (2013), it is apparent that airport operators must exercise “due diligence” in managing 

wildlife hazards to avoid potentially serious liability issues. In the USA, the exercise of “due 

diligence” to manage wildlife hazards initially involves a Wildlife Hazard Assessment (WHA) at 

the airport. Based on the WHA, a Wildlife Hazard Management Plan (WHMP) is usually 

required for airports that are certificated by the Federal Aviation Administration (FAA) for 

passenger service under U.S. Code of Federal Regulations (14 CFR Part 139.337, hereafter 

referred to as Part 139-certificated airports). As of December 2020, there were 520 Part 139-

certificated airports in the USA (FAA 2021b). Airports that are not Part 139-certificated but that 

accept federal grant-in-aid funding may also be required to conduct WHAs and develop WHMPs

(FAA Advisory Circular 150/5200-33C, FAA 2021c).

4. How does an airport manage wildlife hazards?

Managing bird and other wildlife hazards at airports is a complex, public-sensitive endeavor 

involving many species of wildlife governed by the international Migratory Bird Treaty Act and 

various federal, state, and local regulations. For example, 591 species of birds, 51 species of 

terrestrial mammals, 36 species of bats, and 23 species of reptiles were identified in wildlife 

strikes with civil aircraft in the USA, 1990-2019 (Dolbeer et al. 2021). Because of the 

complexity and sensitivity involved in managing wildlife hazards, airports are required to 

employ professional biologists trained in wildlife hazard management at airports to assess 

hazards, provide training, and to assist in the development, implementation, and evaluation of 

WHMPs (14 CFR Part 139.337 and FAA Advisory Circular 150/5200-36B [FAA 2021c]). Such 

professionally developed and implemented management plans minimize the likelihood of 

catastrophic or substantial-damage wildlife strikes on an airport and provide crucial support 

during litigation in the aftermath of any significant strike event that might occur. Cleary and 

Dolbeer (2005) provide detailed information on the development and implementation of these 

management plans as well as on FAA regulations and guidelines regarding wildlife hazards to 

aviation. DeVault et al. (2013) discuss the scientific foundations of wildlife management in 

airport environments. 
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5. What role does USDA-Wildlife Services (WS) play in managing wildlife hazards at 

airports?

The WS program provides federal leadership for resolving conflicts between wildlife and people.

The WS program, with professional biologists available for consultation and other services in all 

50 States and U.S. Territories and for U.S. military installations worldwide, is internationally 

recognized for research and management programs to resolve conflicts between wildlife and 

humans. WS’s National Wildlife Research Center, headquartered in Colorado with field stations 

in 7 other states, provides a scientific foundation for management programs.

The FAA, with two staff wildlife biologists to deal with wildlife hazards to aviation nationwide, 

has historically partnered with the WS program to provide professional assistance to airports. 

The FAA has a Memorandum-of-Understanding (MOU) with WS (signed in 1978; updated in 

1989 and 2005) stating that “FAA or the certificated airport may request technical support from 

WS to lessen wildlife hazards” (Cleary and Dolbeer 2005). In addition, the Department of 

Defense (DoD) has a similar MOU with WS (signed in 1990) for assistance with wildlife 

damage issues at DoD facilities (Cleary and Dolbeer 2005). Finally, the National Association of 

State Aviation Officials (NASAO) and WS have a MOU (signed in 2006 and updated and 

expanded in 2013 to include the FAA) which states that the three organizations have a mutual 

goal “to provide technical and operational assistance and necessary training to the aviation 

community in order to ultimately reduce the risk of wildlife hazards and ensure safer operations 

at airports.” Many wildlife hazard management programs at airports have been developed, 

implemented, or overseen by WS biologists. WS receives no appropriated federal funding to deal 

with wildlife hazards at airports but is authorized by the U.S. Congress to enter into cooperative 

service agreements with airport authorities and other entities to provide services on a costreimbursable basis.

5a. Managing wildlife hazards at airports and air bases is a specialized, public-sensitive 

activity: are WS biologists qualified and trained to work in this environment? 

In 1996, WS developed a 3-day Airport Training Course to ensure that employees conducting 

work at airports understood the airport environment and the regulations, policies, and agency 

roles for both civil and military aviation. In 2010, an additional course (Advanced Airport 

Training) was developed to assist with recertification and cater to longer term airport biologists. 

As of January 2021, 885 WS biologists have successfully passed the FAA-approved Airport 

Training Course (FAA Advisory Circular 150/5200-36B [FAA 2019c]) and 292 biologists have 

taken the Advanced Course. Additionally, because WS biologists address wildlife damage 

management issues throughout the USA and abroad (see section 5b below), WS possesses a 

network of experienced employees to exchange information regarding wildlife damage 

management techniques, especially those best suited for issues arising at airports. Also, WS 

biologists working at airports and military airbases are scientifically supported by WS’s National 

Wildlife Research Center (see DeVault et al. 2013 and Section 5e below).

5b. At how many airports did WS biologists provide assistance in reducing wildlife hazards 

in 2020?

The number of civil and military airports requesting assistance from WS has steadily grown over 

the past 30 years in concert with the increased awareness of the risk that wildlife poses to 

aviation safety. WS assistance grew from primarily short-term consultative work (e.g., 1-day site 
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visits) at about 40 airports in 1990a to 299 staff-years of assistance at 776 airports in 2020 (638

civil and 138 military) in 50 states, 4 U.S. territories, and 14 foreign countries (Table 1; Figures 

1, 2). WS provided full-time (>1 staff year) of assistance at 145 airports in 2020 (Table 2). In 

2020, assistance was provided at 380 (73%) of the 520 Part 139- certificated airports in the USA 

(Table 3). The 380 certificated civil airports where WS assisted served 284 million commercial 

passengers and recorded 13.1 million and 10.6 million commercial and general aviation (GA) 

aircraft movements, respectively, in 2020 (Table 4). The 259 non-certificated civil airports in 

USA where WS assisted recorded 0.5 million and 7.6 million commercial and GA aircraft 

movements, respectively.

5c. What types of assistance were provided by WS biologists at airports to reduce wildlife 

hazards in 2020?

WS biologists provided a wide range of technical and direct management assistance at airports 

(Tables 5, 6; Figure 3). Consultations with airport authorities regarding wildlife issues was the 

most common technical service provided (680 airports) followed by training of airport personnel 

in wildlife identification and control methods (385 airports involving 3,883 personnel). Other 

technical assistance provided included continued monitoring of wildlife, development and 

revisions of Wildlife Hazard Management Plans, Environmental Assessments, and Wildlife 

Hazard Assessments (250, 174, 64, and 36 airports, respectively).

Direct management assistance included lethal removal of hazardous wildlife (393 airports), nonlethal dispersal of hazardous wildlife (349 airports), modification of habitats to discourage 

wildlife (274 airports), and capture and translocation of wildlife away from the airport (190

airports, Table 5). Lethal control of protected species was done under state and federal permits as 

a last option after solely non-lethal options had been determined to be ineffective or impractical.

In addition to work done on airport property, WS biologists provided technical and direct 

management assistance regarding off-airport wildlife attractants at 263 airports (Table 5).

5d. At how many airports did technical or direct management assistance by WS biologists 

result in a reduction, suppression, or prevention of hazards caused by wildlife in 2020? 

WS biologists estimated that technical or direct management assistance resulted in a reduction, 

suppression, or prevention of wildlife hazards at 515 (66%) of the 776 airports where some type 

of assistance was provided (Table 7, Figure 4). This total included 254 (67%) of the 380 Part 

139-certificated civil airports assisted. These estimates of successful intervention are 

conservative. WS biologists indicated that there was insufficient time since management actions 

had been implemented or insufficient information from airport personnel to assess whether or not 

hazards had been reduced, suppressed, or prevented on many airports. Wenning et al. (2004),

Dolbeer et al. (2007, 2014), Dolbeer and Franklin (2013), and Washburn (2019) provided 

summaries of specific accomplishments by WS biologists at airports and airbases nationwide in 

reducing wildlife hazards since 1990. Recent analyses have documented an overall national 

decline in damaging wildlife strikes in the airport environment at Part 139-certificated airports 

during the past 2 decades (Dolbeer 2011, Dolbeer et al. 2014, Dolbeer et al. 2021). The work by 

WS personnel, as documented in this report, has likely been a major factor in the decline in these 

damaging wildlife strikes.

a Years refer to Federal Fiscal Years (e.g., 1990 = 1 Oct 1989-30 Sep 1990).
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 5

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5e. Besides technical and direct management assistance at airports, what other roles does 

WS play in mitigating wildlife hazards to aviation?

WS biologists working at airports and airbases are supported by WS’s National Wildlife 

Research Center (NWRC). NWRC has a field station (located at NASA’s Glenn Research 

Center, Plum Brook Station near Sandusky, Ohio) devoted to applied research in methods to 

mitigate wildlife hazards to aviation. Numerous research collaborations involving NWRC have 

occurred or are ongoing at civil and military airports through interagency and cooperative 

agreements with other government agencies, airports, universities, and private companies (Table 

8). In addition, WS, through an interagency agreement with the FAA, manages the National 

Wildlife Strike Database (NWSD) which contains over 243,000 reports of wildlife strikes with 

civil aircraft in USA, 1990-2020. The NWSD provides the scientific foundation for research and 

management activities and for the development of national policies and regulations related to 

mitigating the risk of wildlife strikes to aircraft (e.g., Cleary and Dolbeer 2005; Dolbeer and 

Wright 2009; Pitlik and Washburn 2012; DeVault et al. 2011; Dolbeer et al. 2014, 2018, 2019;

FAA 2021d).

6. Conclusions 

Because of expanding populations of many wildlife species that are hazardous to aviation and the 

adaptation of these species to urban environments, mitigation efforts to minimize the risk of 

wildlife strikes are increasingly important at both civil and military airports worldwide. In 

response, WS has developed a national network of professional wildlife biologists who are 

highly qualified and specifically trained to deal with these unique, complex, and public-sensitive 

challenges. As documented in this report, WS provides substantial assistance and effective, 

science-based mitigation for a variety of wildlife hazard issues at airports. However, a major 

challenge facing WS is that no Congressional funding is available to provide a foundation for 

wildlife hazard mitigation work. Thus, assistance provided by WS is often limited by the 

availability of funds by cooperators on an annual basis. In many situations, WS is unable to 

address significant wildlife hazard issues requested and desired by cooperators because no 

funding or insufficient funding is available to do the necessary work. 
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Table 1. Staff-years expended and number of civil airports (Part 139 and General Aviation)a and 

military airbases served by USDA-Wildlife Services (WS) biologists in provision of technical and 

direct management assistance to reduce wildlife hazards to aviation, FY 2020.

Number of airports assisted Number of airports assisted

State/

Terr.

WS 

staff 

years

Civil

(P139)

Civil 

(GA)

Military Total

State/

Terr.

WS 

staff 

years

Civil

(P139)

Civil 

(GA)

Military Total

AK 17.69 24 6 13 43 ND 2.05 8 1 2 11

AL 3.46 5 10 3 18 NE 3.02 7 1 1 9

AR 1.26 6 7 1 14 NH 3.28 2 4 6

AZ 3.20 3 2 3 8 NJ 8.02 4 3 1 8

CA 19.69 14 5 12 31 NM 1.47 4 4 2 10

CO 6.44 14 14 3 31 NV 1.88 1 3 4

CT 1.00 4 3 7 NY 11.05 7 2 9

DE 2.14 1 1 2 OH 6.79 12 12 1 25

FL 15.52 5 2 18 25 OK 6.58 2 5 4 11

GA 2.22 4 5 3 12 OR 2.66 5 3 8

GUb 2.27 4 4 PA 8.14 12 7 1 20

HI 35.57 8 4 3 15 PR 1.02 3 3

IA 1.80 7 8 15 RI 1.32 1 5 6

ID 0.08 5 1 6 SC 7.15 8 6 4 18

IL 9.39 18 5 23 SD 0.97 5 3 1 9

IN 2.12 7 5 12 TN 2.95 7 3 10

KS 4.28 7 4 2 13 TX 12.70 17 9 8 34

KY 1.28 6 6 USVI 2.79 2 2

LA 3.02 9 4 2 15 UT 2.87 7 1 1 9

MA 2.66 8 7 1 16 VA 14.34 9 8 6 23

MD 9.08 3 1 2 6 VT 3.73 2 7 9

ME 1.35 4 6 10 WA 8.72 10 11 3 24

MI 4.73 19 6 2 27 WI 3.21 9 25 1 35

MN 2.38 9 25 34 WV 1.89 6 1 1 8

MO 7.42 10 1 1 12 WY 0.04 8 8

MS 2.58 5 1 2 8 Mil_Fgn 4.93 20 20

MT 1.16 7 1 8

NC 11.78 6 4 6 16 Totald 299.11 379 259 138 776

a Part 139 airports are certificated for passenger service (see footnote in Table 3). Military total includes 1

U.S. Air Force Base (Dover) certificated under Part 139; 99 civil airports were joint-use with military.

b Includes 3 airports in Pacific Island Territories outside of Guam.

c U.S. military airbases at foreign locations.

d See Figures 1 and 2 for trends in numbers of airports served and staff-years of assistance, 1999 - 2020.
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Table 2. Distribution of staff years expended at 776 civil and military airports where USDAWildlife Services (WS) biologists provided technical and direct management assistance to reduce 

wildlife hazards to aviation, FY 2020. 

WS staff years expended by number of airportsa

Type of 

airport < 0.10 

0.11 to

0.25 

0.26 to 

0.50 

0.51 to 

0.99 >1.00

Total 

airports

Civilb 483 25 35 18 77 638

Military 27 20 12 11 68 138

Total 510 45 47 29 145 776

a In FY 2020, 299 staff years of assistance was provided at the 776 civil and military airports (Table 1).

b Includes 99 civil airports with a military “joint-use” presence.

Table 3. Number of civil airports (Part 139-certificated and General Aviation) and military 

airbases requesting assistance from USDA-Wildlife Services for wildlife hazard issues, FY 2020.

Airport status

Number (%) of airports 

requesting assistance

Civil: Part 139-certificateda, b 380 (49)

Civil: General Aviation 259 (33)

Military 137 (18)

Total 776 (100)

a The U.S. Code of Federal Regulations (14 CFR Part 139) requires the Federal Aviation 

Administration (FAA) to issue airport operating certificates to airports that serve scheduled and 

unscheduled air carrier aircraft with more than 9 seats or that the FAA Administrator requires to 

have a certificate. Part 139-certificated airports experiencing hazardous wildlife conditions as 

defined in Part 139.337 must conduct formal Wildlife Hazard Assessments and develop Wildlife 

Hazard Management Plans as part of the certification standards. In December 2020, there were

520 Part 139-certificated airports in the USA (FAA 2021c). 

b One of the 138 military airbases held a Part 139 certificate.
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 12

For Public Distribution

Table 4. Number of passenger enplanements and aircraft movements in 2020a at 380 Part 139-

certificated civil airports and 259 non-certificated (General Aviation) civil airports in USA 

requesting assistance from USDA-Wildlife Services for wildlife hazard issues, FY 2020.

Aircraft movements (departures and arrivals)

Airport status

(14 CFR 

Part 139)

Number of 

passenger 

enplanements

CommercialbGeneral 

aviationc Militaryd Total

Part-139-

certificated (380) 283,570,305 13,077,864 10,583,706 1,833,522 25,495,092

Noncertificated (259) 36,908 530,390 7,562,753 712,419 8,805,562

Total 283,607,213 13,608,254 18,146,459 2,545,941 34,300,654

a Passenger enplanement data were obtained from FAA Terminal Area Forecast (TAF, FAA 

2021a) and reduced by 60% to adjust for the overall 60% reduction in passenger traffic in 2020 

because of the Covid-19 outbreak (IATA 2021). Aircraft movements for 336 civil airports were 

obtained from FAA Air Traffic Activity System (ATADS, FAA 2021b). Movement data for 

remaining airports were from the TAF or, if not available from TAF, from 

https://www.airnav.com/.

b Air carrier, air taxi and commuter aircraft.

c Includes itinerate (take off and land at different airport) and local (take off and land at same 

airport) movements.

d Totals exclude over 2 million military and civil aircraft movements at 138 military airbases.
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 13

For Public Distribution

Table 5. Types of technical and operational (direct management) assistance provided by USDAWildlife Services biologists to reduce wildlife hazards at airports, FY 2020. 

Category of 

assistance Type of assistance to reduce wildlife hazards

Number

of 

airports

% of total 

airports 

assisted 

(N = 776)

Technical Consultation regarding wildlife issues 680 88

Training of airport personnela 385 50

Continued wildlife monitoringb 250 32

Wildlife Hazard Management Plan 174 22

Environmental Assessment 64 8

Wildlife Hazard Assessment 36 5

Total airports with Technical Assistance 757 98

Direct management Lethal control of hazardous wildlife 393 51

Non-lethal dispersal of hazardous wildlife 349 45

Habitat modification 274 35

Live-trap/ translocate wildlife from airport 190 24

Total airports with Direct Management 

Assistance 443 57

Off-airportc Total airports with off-airport Technical or 

Direct Management Assistance 263 34

a Number of airports where training took place; personnel from additional airports attended some 

of these training courses (See Table 6).

b Airports where Wildlife Hazard Assessments (WHA) have been completed but monitoring of 

wildlife and wildlife attractants is being done continuously under a WHA protocol to maintain 

the WHA in a current state.

c FAA Advisory Circular 150/5200-33b “Hazardous wildlife attractants on or near airports” 

provides guidance on land uses that have the potential to attract hazardous wildlife within 10,000 

feet of runways and within the flight paths of arriving and departing aircraft within 5 miles of 

runways (FAA 2021d, Pfeiffer et al. 2019).
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 14

For Public Distribution

Table 6. Number of airports where technical training was provided in the identification and 

management of wildlife hazards to aviation and total airport personnel trained by USDAWildlife Services biologists, FY 2020. 

State

Number 

of 

airports

Number of 

persons 

trained State

Number 

of 

airports

Number of 

persons 

trained

AK 32 245 ND 8 68

AL 5 55 NE 9 41

AR 14 14 NH 2 31

AZ 4 46 NJ 2 16

CA 24 117 NM 4 28

CO 21 194 NV 2 12

CT 4 39 NY

DE 1 1 OH 14 82

FL 5 30 OK 2 38

GA 1 8 OR 6 86

GU 4 99 PA 14 259

HI 7 149 PR 2 20

IA 10 62 RI

ID 3 55 SC 8 34

IL 13 137 SD

IN 7 49 TN 10 76

KS 5 41 TX 19 231

KY 4 223 USVI 2 12

LA 2 12 UT 4 47

MA 7 65 VA 12 174

MD 1 10 VT 2 11

ME 3 60 WA 10 145

MI 15 84 WI 10 57

MN 6 54 WV 6 75

MO 11 125 WY 6 57

MS 4 31 Mil-Fgna 6 124

MT 7 60

NC 5 94 Total 385b 3,883c

a U.S. military airbases at foreign locations.

b Personnel from several airports sometimes attended training courses provided by WS at an 

airport; thus, total airports from which personnel received training is greater than indicated. 

c See Figure 3 for trends in number of airports where training was conducted and number of 

airport personnel trained, 2001 - 2020. 
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 15

For Public Distribution

Table 7. Number of Part 139-certificated airports, non-certificated airports, and military airbases at

which technical or direct management assistance by USDA-Wildlife Services (WS) biologists resulted 

in an estimated reduction, suppression, or prevention of hazardous conditions caused by wildlife, FY 

2020. 

Number of airports (% of total airports assisted)

Part 139-

certificated civil 

airports 

(n = 379a)

Noncertificated 

civil airports 

(n = 259b)

Military 

airbases

(n = 138)

All 

airports 

(n = 776)

Reduction of hazards from 

target wildlife species c 249 (66) 152 (59) 99 (72) 500 (64)

Suppression of hazards from 

target wildlife species d 244 (64) 140 (54) 96 (70) 480 (62)

Prevention of hazards from 

target wildlife species e 213 (56) 114 (44) 92 (67) 419 (54)

Reduction, suppression, or 

prevention of hazards from 

target wildlife f, g

254 (67) 161 (62) 100 (72) 515 (66)

a In addition, 1 of the 138 military airbases held a Part 139 certificate.

b General Aviation airports.

c As examples, airport installed anti-perching devices or removed vegetation attractive to hazardous 

wildlife because of WS recommendation; WS successfully initiated program to remove hazardous 

wildlife from the airport. 

d Successful WS direct management activities or technical assistance recommendations initiated in 

previous years were continued or maintained in 2020 (e.g., continued management of vegetation, 

continued removal of deer as a follow-up to more extensive removal initiated in earlier year to initially 

get problem under control).

e WS recommendation or intervention resulted in prevention of development or activity that would 

have resulted in increased wildlife numbers at airport (e.g., prevention of on-airport wetland 

mitigation, landfill expansion near airport, or planting of landscape vegetation attractive to wildlife).

f These estimates of successful intervention are conservative because WS biologists indicted that there 

was insufficient time since management actions had been implemented or insufficient information 

from airport personnel to assess whether or not hazards had been reduced, suppressed, or prevented on 

at least 50 airports.

g See Figure 4 for trends in the reduction, suppression, or prevention of hazards from target wildlife at 

airports served by WS, 2002-2020.
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 16

For Public Distribution

Table 8. Science-based activities provided by USDA-Wildlife Services (WS) to support 

technical and direct management assistance efforts at airports and within the broader aviation 

industry to mitigate wildlife risks to aviation, FY 2020.

WS program Primary activities Sponsorsa

Operations • Managed the National Wildlife Strike Database and produced 

annual strike report summarizing data from 1990-2018,

• Partnered with Embry Riddle Aeronautical University for 

technical support of NWSD and to participate in various 

outreach programs within aviation industry to promote the 

accurate reporting of wildlife strikes, 

• Worked with Commercial Aviation Safety Team (CAST) to 

monitor trends in high-risk strikes (e.g., Dolbeer 2016) and to 

update CAST concerning USDA WS NWRC activities related 

to NTSB recommendation A-10-87,

• Worked with USAF Safety Center, U.S. Navy, Air National 

Guard and USDA WS NWRC to prioritize research projects 

related to wildlife hazards and military aviation,

• Conducted outreach through ARCCoS training events,

• Conducted outreach through AAAE ASOS schools,

• Provided 1 initial and 2 advanced Wildlife Hazards at Airports 

trainings for USDA personnel, WI DOT (1) and USFWS (1).

• Developing ConOps for BDR

FAA/USN/

ANG

Researchb • Development of aircraft lighting to increase visibility of aircraft 

to birds,

• Movement patterns of raptors and other birds near airports, 

• Evaluation of alternative land covers to mitigate strike risk and 

reduce maintenance costs for airports,

• Evaluating unmanned aerial systems as bird hazing tools,

• Evaluating unmanned aerial systems in wildlife survey 

applications.

FAA

a Air National Guard (ANG); Federal Aviation Administration (FAA); U.S. Navy (USN).

b Research directed by the National Wildlife Research Center, Ohio Field Station, Sandusky, Ohio.
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 17

For Public Distribution

Figure 1. Airports assisted by USDA-Wildlife Services (WS) in provision of technical and direct 

management assistance to reduce wildlife hazards, 1998 - 2020. In 2020, WS personnel provided 

299 staff-years of assistance at 776 airports (638 civil, 138 military) in all 50 U.S. States, 4 U.S. 

Territories, and 14 foreign countries (see Table 1). Data on airports assisted are not available 

before 1998, but WS personnel estimated only about 40 airports were assisted in 1990 (primarily 

1-day site visits or telephone consultations) with a steady increase to 193 airports in 1998.
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 18

For Public Distribution

Figure 2. The number of staff years provided by USDA-Wildlife Services personnel in technical 

and direct management assistance to reduce wildlife hazards at civil and military airports 

increased from 100 in 2001 to 298-301 in 2017 - 2020. Data on staff years are not available 

before 2001, but WS personnel estimated <1 staff year of assistance was provided in 1990 

(primarily 1-day site visits or telephone consultations) with a steady increase to 100 staff years in 

2001.

100

117 115 116

131

144 143

160

173

196

215

232

251

280 276

288

300 298 301 299

0

50

100

150

200

250

300

350

20012002200320042005200620072008200920102011201220132014201520162017201820192020

USDA WS staff years assisting airports
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 19

For Public Distribution

Figure 3. The number of airport personnel trained by USDA-Wildlife Services in identification 

and management of wildlife hazards to aviation and the number of airports where training took 

place, 2001 to 2020 (see Table 6). Training activity was reduced in 2020 because of restrictions 

imposed by the Covid-19 epidemic.
USDA-Wildlife Services Assistance at Airports, FY2020—Begier, Dolbeer, & Washburn 20

For Public Distribution

Figure 4. Number of airports and military airbases at which technical or direct management 

assistance by USDA-Wildlife Services (WS) biologists resulted in an estimated reduction, 

suppression, or prevention of hazardous conditions caused by wildlife, 2002 - 2020. These 

estimates of successful intervention are conservative because WS biologists indicted that there 

was insufficient time since management actions had been implemented or insufficient 

information from airport personnel to assess whether or not hazards had been reduced, 

suppressed, or prevented on 40 to 60 airports each year (see Table 7).