National Statistics

National Statistics

Snowy owls may pose hazards to aircraft.Number of “Part 139”-certificated airports (“Part 139”-certificated airports serve scheduled and unscheduled air carrier aircraft with more than 9 seats), non-certificated airports, and military airbases at which technical or direct management assistance by WS biologists resulted in a reduction, suppression, or prevention of hazardous conditions caused by wildlife, FY 2013.


Number of airports (% of total airports assisted)


“Part 139”- certificated civil airports
(n = 396a)

certificated civil airports
(n = 362b)

Military airbases

(n = 850)

Reduction of hazards from target wildlife speciesc

237 (60)

212 (59)

75 (82)

524 (62)

Suppression of hazards from target wildlife speciesd

235 (59)

190 (53)

74 (80)

499 (59)

Prevention of hazards from target wildlife speciese

179 (45)

146 (41)

64 (70)

389 (46)


Reduction, suppression, or prevention of hazards from target wildlife

264 (67)

245 (68)

78 (85)

587 (67) f,g

a In addition, 1 of the 92 military airbases held a Part 139 certificate.

b Comprised of  354 General Aviation airports in USA and 8 foreign civil 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 2013 (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 For comparison, WS biologists estimated that technical or direct management assistance resulted in a reduction, suppression, or prevention of hazards from target wildlife at 409 airports in 2002, 441 airports in 2003, 479 airports in 2004, 483 in 2005, 518 in 2006, 548 in 2007, 582 in 2008, 602 in 2009, 568 in 2010, 546 in 2011, and 568 in 2012.

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