Bird use, bird hazard risk assessment, and
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- Bird Hazard Ranking System
- Bird Hazard Levels of Concern
- Bird Hazards in the Pickering Area
Hazardous Bird SpeciesThe consequence of a bird strike varies with the weight and density of the bird, the impact speed, and the number of birds that are struck during a bird-strike event. Therefore, information regarding the physical characteristics of bird species and their nesting, feeding, flocking, and flying characteristics are needed to establish a generalized category of risk for each species or group. The information derived from this step, when used with information from the previous step, enables a determination of bird species that are most likely to result in a catastrophic loss of human life. In the following sections, we develop a generalized ranking system that distinguishes among the bird groups by the degree of risk that they pose to aircraft safety. The ranking system is general and could be applied anywhere in Canada. To make the system directly applicable to the Pickering situation, we apply the ranking system to the main bird species that regularly occur in southern Ontario. Bird Hazard Ranking SystemThe bird hazard ranking system is based on the size of the birds, their flocking characteristics, and their flight behaviour. The size of the bird is an important determinant of the damage that it can cause to an aircraft. Obviously, large birds cause more damage than smaller birds. The average weight of the bird is used in this system. The weight is more important than the overall size because it is the density of the bird that determines actual damage. The flocking behaviour of the species is important because it affects the probability that more than one individual is likely to be involved in a bird-strike event. A bird-strike event involving a flock of birds can lead to birds being ingested into more than one aircraft engine, thereby greatly increasing the risk of an accident. The worst example of this was a Lockheed Electra that ingested a flock of starlings into three of its four engines just after take-off from Boston’s Logan Airport. The aircraft lost power, stalled, and crashed into Boston Harbor, with the loss of 62 lives plus 9 injured. Thus, dense flocks of birds are usually more dangerous than single birds. The flight behaviour of birds is an important consideration when assessing risk to aircraft. During their annual migrations, birds can fly at high altitudes, often at several thousand feet above ground. These migrations can pose threats to aircraft safety, but they are independent of local land-uses and are not considered here. In the vicinity of an airport, it is the local movements that occur on a daily basis that are most relevant to aircraft safety. Some species always fly close to the ground, whereas others, such as gulls and hawks regularly fly at higher altitudes of 1000 to 1500 ft agl. Birds at those altitudes can pose a risk to aircraft on approach and departure to the airport. Dolbeer et al. (2000) have analyzed U.S. civilian bird strike data from the Federal Aviation Administration (FAA) data base to rank wildlife species in terms of the damage caused by strikes with each species. The ranking system that has been developed here is consistent with their results. The general categories used in the Bird Hazard Ranking System are defined below from highest risk (Level 1) to lowest risk (Level 6). Level 1 – very large, flocking birds Level 1 species are very large birds that weigh 1.8 kg or more and occur in flocks during flight. The weight of 1.8 kg was chosen because that is the weight (4 lbs) of a single bird that many of the jet engines in use today have been designed to be able to survive. Examples of Level 1 species include geese, cranes, and cormorants. Level 2 – very large, solitary birds large, flocking birds Level 2 species include solitary, very large species, such as vultures, and large, flocking species, such as Mallards or Great Black-backed Gulls. A large species is defined here as one with an average weight of from 1 to 1.8 kg (2.2-4 lbs). Level 3 – large, solitary birds medium-sized, flocking birds Level 3 species include solitary, large species, such as a Red-tailed Hawk, and medium-sized flocking species, such as the American Crow. A medium-sized species is defined here as one with an average weight of 300 to 1000 g (0.7-2.2 lbs). Level 4 – medium-sized, solitary birds small, flocking birds Level 4 species include solitary, medium-sized species and small, flocking species. A small species is defined here as one with an average weight of 50 to 300 g (0.1-0.7 lbs). An example of a small, flocking species is the European Starling. Level 5 – small, solitary birds very small, flocking birds Level 5 species include solitary, small species, such as the Eastern Meadowlark, and very small, flocking birds, such as swallows. A very small bird is defined as one with an average weight of less than 50 g (0.1 lb). Level 6 – very small, solitary bird Level 6 species include very small, solitary birds such as warblers, vireos, and sparrows. Bird Hazard Levels of ConcernThe six hazard levels in the Bird Hazard Ranking System are ranked in approximate order from most severe to least severe. Based on the worldwide history of bird strike incidents, it is clear that each of Levels 1 to 4 can present significant safety hazards. The small, flocking birds in Level 4 have caused significant aircraft accidents. The Lockheed Electra brought down by a flock of starlings in Boston was mentioned earlier. Also, a flock of Brown-headed Cowbirds brought down a Lear 24 jet taking-off from DeKalb-Peachtree Airport in Atlanta, Georgia, in March 1973. The aircraft lost power in both engines and crashed with the loss of 7 lives. Hazard Levels 5 and 6 generally have not caused significant bird strike accidents to civilian aircraft, although some minor damage could occur. There are a large number of strikes with species in Hazard Levels 5 and 6, particularly in the airport environment where both the birds and the aircraft are close to the ground. Many of those strikes go unnoticed by the flight crew and airline maintenance staff, but are detected by the presence of dead birds found on or near airport runways by bird control and runway patrol staff. It should not be assumed, however, that all strikes with Level 5 species are harmless. For example, a single American Kestrel caused significant damage to a Boeing 737 at Louisville Airport in a Category C incident. In the following analyses, emphasis is placed on the Bird Hazard Levels 1 to 4. Levels 5 and 6 are not considered because they do not pose a significant risk of a Category A or Category B incident. Bird Hazards in the Pickering AreaIn this section, we evaluate the general Bird Hazard Ranking System in terms of the birds species that are known to occur in southern Ontario in general, and the Pickering Area in particular. Knowledge of bird species, numbers, and behaviour in the area is derived from several studies and from personal experience. The studies include the original 18-month bird studies conducted by LGL Limited (and the senior author) during the planning stages for the new Toronto (=Pickering) International Airport in 1973-74, the one-year study of bird populations conducted in Durham Region by Bird and Hale Ltd. for the Interim Waste Authority in 1992-93, the bird population study conducted in the Pickering area for Transport Canada by JWEL in 1997, and the 3-month update of the JWEL study conducted in the fall of 2001 as part of the present study. Based on the above information, the following potentially hazardous species are of concern in the Pickering area. The following list contains species that are directly affected by land-uses in the Pickering area. There are other species that pass through the area, primarily on migration, and are not influenced by local land-uses. Nonetheless, those species could present a safety hazard while in the area. As an example, the Canada Goose is a very large, flocking species that is affected by local land-use and therefore is a Level 1 hazard species. Double-crested Cormorants and Common Loons are also very large species, but they pass over the Pickering area independent of local land-use patterns, and thus, they are not included in the following rankings. The table below ranks bird species by category of risk they present to aircraft. Level 1 - Canada Goose (very large, flocking) Level 2 - Great Blue Heron (very large, solitary) Turkey Vulture (very large, solitary) Bald Eagle (very large, solitary) Mallard (large, flocking) Black Duck (large, flocking) Great Black-backed Gull (large, flocking) Herring Gull (large, flocking)
Ring-billed Gull (medium, flocking) Rock Dove (medium, flocking) American Crow (medium, flocking) Level 4 - Cooper’s Hawk (medium, solitary) Northern Harrier (medium, solitary) Mourning Dove (small, flocking) European Starling (small, flocking) Red-winged Blackbird (small, flocking) Common Grackle (small, flocking) Brown-headed Cowbird (small, flocking)
American Kestrel (small, solitary) Killdeer (small, usually solitary) Eastern Meadowlark (small, solitary) Snow Bunting (very small, flocking) House Sparrow (very small, flocking) Migrating sparrows (very small, flocking)
It should be remembered that the above classes are not clear-cut categories but rather represent points along a continuum of risk. Directory: media -> documents -> ontario-eng documents -> Do remittances have a flip side? A general equilibrium analysis of remittances, labor supply responses and policy options for Jamaica* Maurizio Bussolo and Denis Medvedev documents -> Cosida teleconference: Collegiate Communications Issues & Challenges: With an nfl perspective michael signora documents -> Suny cortland red dragons athletic awards (Updated: 8/15/11) all-america name Sport Honor documents -> Cosida st. Louis Convention Schedule as of June 18, 2012 (subject to change) Saturday, June 23 documents -> For release: Friday, May 31 – 12 noon (edt) Please visit the Capital One Academic All-America® website documents -> Time location 9 am – 10 am Lindell Program Committee Meeting documents -> James ramsey of florida state headlines capital one academic documents -> Division II basketball teams documents -> Matt howard of butler, austin meier of msoe ontario-eng -> Airport wildlife management and planning part 2 (car 302. 201-302. 206) bulletin #32—winter 2002 Download 124.42 Kb. Share with your friends:
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