Appendix K Bird/Aviation Assessment

Transcription

1 Appendix K Bird/Aviation Assessment August 2007

2 ASSESSMENT OF BIRD HAZARDS TO AIRCRAFT SAFETY ASSOCIATED WITH THE EXPANSION OF THE ROSEWARNE DRIVE LANDFILL, ONTARIO by Rolph A. Davis, Ph.D. LGL Limited environmental research associates P.O. Box 280, 22 Fisher St. King City, ON L7B 1K for Dillon Consulting Limited 235 Yorkland Blvd., Suite 800 Toronto, ON M2J 4Y8 LGL Report No. TA August 2007

3 TABLE OF CONTENTS Introduction...K-1 Study Approach...K-1 Proposed Landfill Expansion...K-1 Muskoka Airport...K-3 Bird Species of Concern...K-3 Study Findings...K-5 Rosewarne Drive Landfill (Bracebridge)...K-6 Stisted Landfill (Huntsville)...K-7 Beiers Road Landfill (Gravenhurst)...K-7 Assessment of Potential Bird Hazards to Aircraft Safety...K-8 Potential For Interactions...K-8 Expected Numbers of Hazardous Birds at the New Landfill...K-8 Existing Situation at the Muskoka Airport...K-9 Transport Canada Bird Strike Data...K-9 Interview with Airport Manager...K-9 Source of Gulls at Airport...K-11 Potential Risks to Aviation Safety Associated with Expansion of the Rosewarne Drive Landfill...K-11 Conclusions and Recommendations...K-11 Acknowledgements...K-11 Figure K-1 Location of Airport Runway

4 Introduction The District of Muskoka is planning to expand the existing Rosewarne Drive Landfill in Bracebridge across the road to the west. The existing fill area will be capped. The existing and proposed expansion sites are located to the NNE of the Muskoka Airport (see Figure K-1). Aircraft using the main runway at the airport fly toward the landfill and there is a need to assess potential interaction with birds that are attracted to the landfill. It has been well documented that landfills in southern Ontario can attract large numbers of birds that can pose a hazard to the safety of aircraft in the vicinity. To evaluate the risk to aircraft safety posed by the expanded landfill, LGL Limited was retained to conduct a study of the situation and determine whether there would be a significant risk associated with the operation of the Rosewarne Drive Landfill Expansion. Study Approach The study approach was to use a standard methodology that we have used in many other similar landfill/airport studies. This approach involved examining existing landfills in the area to determine present levels of bird use. Using these data, the numbers of hazardous birds likely to use the landfill expansion was determined. Then, aircraft numbers and traffic patterns were examined to see if there were likely to be interactions with birds attracted by the landfill. A risk analysis was conducted. Field work in the area was conducted during September and early October 2006 to determine bird use of the area at that time. In addition to the field work, the author has about 40 years of experience with birds in the area through being a summer resident in Muskoka during that period. Proposed Landfill Expansion The details of the proposed landfill expansion are discussed in other documents forming part of this environmental assessment. For the purposes of this analysis, the following are the main elements of the expansion. The expansion will be directly opposite the existing landfill across Rosewarne Drive. Initially, the landfill expansion will accept waste from the Bracebridge area as it currently does. However, in about 10 years, the existing landfills in Huntsville and Gravenhurst will have reached capacity and will be closed. At that time, the waste from the Huntsville and Gravenhurst areas will be diverted to the Rosewarne Drive Landfill expansion. Some of that increase in waste will be reduced by additional diversion (household organics) that will be instituted in the next few years. Countering that will be the continued population growth in the region. K-1

5 FIGURE K-1. Location of specific facilities mentioned in the text. K-2

6 Muskoka Airport The Muskoka Airport (YQA) is essentially a single runway operation although there is a short cross-wind runway. The main runway (18/36) is a north-south asphalt runway that is 6000 ft (1818 m) long and 150 (45 m) ft wide. There is a non-directional navigation beacon (NDB) located 3.5 nautical miles NE of the runway. The NDB provides location information for aircraft on VFR (visual flight rules) flights into the airport. More recently, a GPS approach system has been installed and will likely take over from the NDB. The cross-wind runway (09-27) is an east-west turf runway that is 2180 ft (661 m) long and 250 ft (76 m) wide. The cross-wind runway is closed from November 1 to May 1. The vast majority of the aircraft traffic at the airport, and all of the turbine aircraft, use the main runway. The aircraft traffic at the Muskoka Airport has been steadily increasing over the past few years. The number of aircraft movements has increased from 12,408 in 2000 to 15,391 in An aircraft movement is one landing or take-off at the airport. Of the movements in 2005, 679 were by jet aircraft, 1,076 were turbo-prop aircraft, 12,670 were piston-engine aircraft, and 966 were rotary-winged aircraft or helicopters. Although piston-engine aircraft can be damaged by collisions with birds, the main safety concern is related to jet aircraft and turbo-prop aircraft. These aircraft travel at higher speeds than do piston-engine aircraft and their turbine engines can ingest birds that damage the fan blades in the engine resulting in the loss of power. Most helicopters have turbine engines that can also ingest birds, however, a more common risk to helicopters is damage to the windscreen caused by bird strikes. Bird Species of Concern Ontario landfills may attract species of birds that can pose a hazard to the safety of aircraft that use nearby airports. Species of concern are those that are large enough to damage an aircraft if struck, or smaller species that occur in dense flocks, which results in many birds being involved in the case of a strike. The behaviour of the bird is also important. Those species that fly at high altitudes and regularly travel long distances are more likely to encounter flying aircraft than are species that tend to be sedentary and remain close to the ground. Finally, the most important behaviour trait for the purpose of the present analysis is attraction to the landfill. There are several species, such as cormorants, geese, ducks, and hawks that can present serious hazards to aircraft safety near airports but these species are not associated with landfills and, therefore, are not relevant here. The species that cause the most concern at landfills are very often gulls. They are opportunistic and feed intensively on edible food waste at landfills. Flocks of gulls often ride thermal updrafts and tower high into the sky, sometimes reaching altitudes over K-3

7 300 m (~1,000 ft) above ground. Outside of the nesting season, gulls roost communally at night on large waterbodies that are often many kilometres from daytime feeding areas, such as landfills. Gulls twice-daily flights between night roosts and landfills can intersect aircraft approach/departure paths at airports that are distant from the landfill. The most common gull species in Muskoka are the Herring Gull and the Ring-billed Gull. Bonaparte s Gull pass through on migration and an occasional individual species such as Great Black-backed Gull and Lesser Black-backed Gull may occur. Gulls are present inland in Muskoka only from spring to fall. During winter when all open water has frozen, gulls leave the Muskoka area or at least retreat to Georgian Bay when it remains ice-free. Herring Gulls and Ring-billed Gulls frequent landfills throughout Ontario with peak numbers usually occurring in late summer and fall. In August, young-of-the-year gulls are flying and can increase the numbers of gulls at landfills. During fall, migrant gulls from further north can increase the numbers at landfills. Herring Gulls nest in small colonies or as single pairs on small islands and spits throughout central and northern Ontario (Cadman et al. 1987). The first Atlas of the Breeding Birds of Ontario (published in 1987) shows confirmed breeding by Herring Gulls throughout central Ontario. Preliminary data from the second breeding bird atlas project, now underway, shows a similar distribution pattern (Birds Ontario 2006). The Ring-billed Gull has more restricted breeding range in Ontario being heavily concentrated along the shores of the Great Lakes (Birds Ontario 2006). It is smaller than the Herring Gull and has a more southerly distribution. It is the most common breeding gull on the Great Lakes but has become quite common in Muskoka in the past 2-3 decades. Although nesting colonies on the Great Lakes can be very large (tens of thousands of pairs), the few colonies away from the Great Lake tend to be small, with fewer than 100 pairs. The Ring-billed Gull is smaller than the Herring Gull and is dominated by that species at landfills. Therefore, ring-bills feed at landfills only when there is excess food available or when Herring Gulls are not common. Ring-billed Gulls are opportunistic and adapted to feeding at transitory food sources. In addition, to the locations noted above, Ringbilled Gulls are found in fields and on lakes. Observations on Lake Muskoka indicate that Ring-bill numbers have increased in the past couple of decades. They are frequently seen aerial feeding at swarms of damsel flies and other insects. For example, Ring-billed Gulls were feeding on flying insects at the mouth of the Muskoka River in late June in Surprisingly, no nesting Ring-billed Gulls were found on the Muskoka lakes during the period of the second Ontario Breeding bird Atlas (Birds Ontario 2006). K-4

8 The Bonaparte s Gull nests in trees in the boreal forest zone of Canada, east to James Bay. This small gull migrates through Muskoka in spring and fall but it remains on and over water; it does not feed at landfills. Therefore, the species is not a concern with regard to this study. The Turkey Vulture has been expanding its range northward in Ontario (Cadman 1987) and is now common in central Ontario from spring to early fall. Turkey Vultures are very large soaring birds that feed primarily by scavenging on dead animals. The Turkey Vulture is the only bird species in North America that hunts using a sense of smell. Turkey Vultures frequent some, but not all, landfills in eastern North America. The American Crow nests throughout central Ontario. Flocks are seen throughout Muskoka primarily in open areas and urban areas. Crows often feed at landfills but usually do not feed when equipment and personnel are active near the waste. They are more likely to be present at landfills early in the morning. The Common Raven is a year-round resident throughout Ontario north of the southern edge of the Canadian Shield (Cadman et al. 1987, Birds Ontario 2006). Like gulls, ravens are very opportunistic foragers, and commonly feed at landfills, dumpsters and other human sources of food. Common Ravens are widespread in fairly small numbers in southern Muskoka. European Starlings commonly feed at landfills throughout most of North America. This introduced species occurs in most areas occupied by humans, including much of central Ontario (Cadman et al. 1987:342). Blackbirds, including Red-winged Blackbird, Common Grackle, Brown-headed Cowbird, and Rusty Blackbird, occur in central Ontario. Starling and blackbirds are flocking species that can occur in large, dense flocks that can be a hazard to aircraft in some areas. Study Findings The original plan was to study bird use of the existing Rosewarne Drive Landfill since that would provide a good estimate of the numbers and species of birds that would likely use the expansion landfill. However, the existing Rosewarne Drive Landfill is near capacity and is only taking a limited amount of waste. Household waste collected during scheduled residential and commercial pick-ups is now diverted to District of Muskoka Landfills in Huntsville and Gravenhurst with most going to Beiers Road Landfill in Gravenhurst. Thus, the numbers of birds present at the existing Rosewarne Drive Landfill were not indicative of the numbers that would be present at the expansion. To address this issue, surveys were also conducted at the Stisted Landfill in Huntsville and the Beiers Road Landfill in Gravenhurst. Based on many years of studies of birds at landfills in the Great Lakes region, it is evident that the numbers of birds using landfills in late summer (late August-early K-5

9 September) is near the annual maximum. At this time of year, gulls generally arrive at the landfill in the morning and stay there until late afternoon. The numbers at landfills in the absence of bird control efforts tend to be quite stable from day to day at this time of year. Therefore, surveys at the three landfills were conducted in mid to late morning in the first half of September Rosewarne Drive Landfill (Bracebridge) The Rosewarne Drive Landfill accepted only tonnes of household waste during the 5-month period from 1 April to 31 August All of this waste was delivered to the drop-off area on the site by residents of the area. The waste was later moved to the landfill active disposal area by staff. The Rosewarne Drive Landfill was surveyed on 8 September 2006 (10:35-11:40) and 11 September (08:10-08:30). Small numbers of gulls were present during each visit. On the 8 th, there were 95 Herring Gulls present and 3 Ring-billed Gulls. Of the Herring Gulls, 40 were adult birds, 40 were sub-adults (age 1-3), and 15 were young-of-theyear. The Ring-bills consisted of 2 adults and 1 sub-adult. On 11 September, there were 65 Herring Gulls present at the landfill at 08:20 but stragglers were still arriving from the west. Ring-billed Gulls were more common away from the landfill. They were always present at the large commercial area along Highway 118 on the west side of Bracebridge. As many as 70 Ring-billed Gulls were seen there on 22 September. On the same day, there were 42 Ring-billed Gulls below the falls on the Muskoka River. The two groups totaled 112 gulls. There were 10 Turkey Vultures present near the Rosewarne Drive Landfill on 8 September. Three of these birds were loafing in two large white pines near the active disposal area and the other 7 were soaring and may or may not have been associated with the landfill. There were no Turkey Vultures present at the landfill early on 11 September indicating that the vultures were not roosting at the landfill at night. On September 8, there were also 10 American Crows; 2 Common Ravens; and 25 European Starlings at and near the site. Discussions with landfill staff indicated that the numbers of gulls and vultures at the landfill were significantly reduced after the household waste was diverted to the other landfills. K-6

10 Stisted Landfill (Huntsville) The Stisted Landfill is located in a remote forested area west of Lake Vernon, which is west of Huntsville. This landfill accepted 1,347.5 tonnes of household waste during the 1 April 31 August 2006 period. The Stisted Landfill accepted more than 4.5 times as much waste as did the Rosewarne Drive Landfill. The Stisted Landfill was surveyed on 11 September from 09:15 to 10:20. A total of about 200 gulls were present at the landfill. Of these, 150 were Herring Gulls and 50 were Ring-billed Gulls. About 55 of the Herring Gulls were young-of-the-year and 95 were adult and sub-adult birds. Most (44) of the Ring-billed Gulls were adult or subadult birds with only 6 young-of-the-year being present. It is apparent that Ring-billed Gulls were able to feed at the Stisted Landfill where more food was available than at the Rosewarne Drive Landfill. There were 5 Turkey Vultures over the site. There were also 5 Common Ravens and 4 American Crows around the site during the brief survey. Discussions with the equipment operator indicated that gull and vulture numbers at the site had increased in late August. Beiers Road Landfill (Gravenhurst) The Beiers Road Landfill is located south of the Town of Gravenhurst adjacent to Highway 11. It is about 11 km SSW of the Muskoka Airport. During the 1 April 31 August period, the Gravenhurst Landfill accepted 3,865.8 tonnes of household waste, about 13 times the amount of household waste accepted at the Rosewarne Drive Landfill. The Beiers Road Landfill was surveyed from 11:40 to 12:20 on 11 September. There were approximately 500 gulls present; ~450 Herring Gulls and ~50 Ring-billed Gulls. The Herring Gulls were about 30% (135) young-of-the-year and 70% (315) adults and sub-adults. The larger waste stream at this landfill supported substantially more gulls than did the other two landfills. Large numbers of Turkey Vultures used the Beiers Road Landfill. An estimated 50 vultures were present during the survey. The birds sat in a group of large white pines that overlooked the active disposal area and on the ground surrounding the disposal area. The vultures were feeding at the disposal area even when the operating equipment was nearby. This is unusual since Turkey Vultures usually avoid humans and operating equipment. There were also 30 American Crows at the edges of the active disposal area. K-7

11 The harbour on Lake Muskoka in Gravenhurst also supported Ring-billed Gulls with a maximum of 65 birds at 17:20 on 5 October. Other observations were 19 at 12:50 on 11 September and 32 at 15:20 on 12 September. In most cases, there were fewer than 10% young-of-the-year birds present. Potential For Interactions Assessment of Potential Bird Hazards to Aircraft Safety The existing Rosewarne Drive Landfill is about 8.6 km NNE of the north end of Runway 18/36 at the Muskoka Airport. The proposed landfill expansion will be approximately 8.5 km NNE of the north end of the runway. An aircraft taking off on the Runway 36 and following runway-heading to the north would pass perpendicular to the landfill at a distance of 8.0 km from the runway end. At that point, the aircraft would be 3.2 km west of the existing landfill and 2.9 km west of the proposed landfill expansion. Lake Muskoka is the largest lake close to Bracebridge. It is the focus of activity for Herring Gulls in the area. There is a long-standing Herring Gull colony at the Eleanor Island National Wildlife Area in southern Lake Muskoka. Based on personal observations, this colony has been present for well over 50 years. There is also a night gull roost associated with the colony. Gulls returning to Lake Muskoka from the Rosewarne Drive Landfill are likely to follow the Muskoka River before heading overland toward the Eleanor Island. These birds would cross the above-noted aircraft flight-line at a distance of 4.8 km north of the north end of the main runway. Birds traveling between the landfill and the Bracebridge Sewage Lagoons (which are regularly used by small numbers of Ring-billed Gulls), would cross the aircraft flight line 4.1 km north of the main runway. The gull flight patterns from the landfill to Lake Muskoka do not take the gulls toward or near to the airport. Aircraft are at relatively high altitudes at distances of 8-9 km from the runway and they will interact with birds at the landfill only if they are towering above the landfill at altitudes of 300 m (~1000 ft) to 600 m (~2000 ft) above ground level. Gulls and vultures do soar up to these altitudes in the right conditions with strong updrafts or rising thermals. They may also be found at these altitudes as they drift toward the lake in the late afternoon. Gulls are more likely to encounter lower aircraft as the gulls fly above the Muskoka River toward Lake Muskoka. Expected Numbers of Hazardous Birds at the New Landfill It is not possible to determine the numbers of hazardous species likely to occur at the Rosewarne Landfill expansion simply by looking at the numbers presently using the site. K-8

12 Clearly, the limited amount of waste now accepted by the site has reduced the bird numbers that are using the site. When the expansion opens, the amount of household waste will increase as all of the Bracebridge waste will be deposited there. Based on the surveys of the three landfills in 2006, it is estimated that the landfill expansion could attract gulls and Turkey Vultures similar to previous years when all Bracebridge waste was disposed at the site. This estimate takes no account of the potential success of proposed waste diversion programs (i.e. Household organics) to be instituted in the near future. When the landfills in Gravenhurst and Huntsville are closed in about 10 years and all of the household waste is deposited at the Rosewarne Drive Landfill expansion, then it is possible that the landfill expansion will attract gulls and Turkey Vultures. This estimate assumes that most of the birds from the three landfills will congregate at the Rosewarne Drive Landfill. It also makes allowance for the continuing increases in populations of gulls and Turkey Vultures in southern Ontario over the next ten years but it does not make allowance for successful waste diversion programs that will reduce the amount of edible waste accepted at the landfill. Transport Canada Bird Strike Data Existing Situation at the Muskoka Airport Bird and mammal strikes at airports are to be reported to Transport Canada although until 2006, the reporting was not mandatory. Bruce MacKinnon of Transport Canada provided a printout of the wildlife strikes at Muskoka Airport that had been reported from 1995 through early During that approximately 11-year period, there were 16 reported wildlife incidents including 11 bird strikes. The other five incidents involved mammals: four near misses and one strike. Three of the mammal incidents involved moose and two involved unidentified mammals. Reported bird strikes averaged about one per year although they were not spread evenly in every year. Eight of the bird strikes involved gulls, one involved Canada Geese, and two involved unidentified birds. All of the bird strikes occurred on the airport property. It is clear that there has been a low-level problem with gulls at the Muskoka Airport for over ten years. The critical question is whether these gulls were in any way associated with the landfills in the area. The answer is no, as discussed toward the end of the next section. Interview with Airport Manager The author interviewed the Manager of the Muskoka Airport, Mr. Mark Stirling. Mr. Stirling has worked at the airport for 6 years and has been the Manager since August of He is very knowledgeable about the birds and mammals in the area K-9

13 and about the actions that the airport has taken to reduce bird hazards. The Muskoka Airport is in the process of completing a Transport Canada mandated Risk Assessment and Wildlife Management Plan for the airport. This is a nation-wide requirement for all airports that are certified by Transport Canada. It is part of an effort to upgrade wildlife control at airports and to increase awareness among airport operators about the bird hazard to aircraft issue. Airport staff conduct bird control, as necessary, at the airport using pyrotechnics to scare birds away. The pyrotechnics are reinforced by using lethal control on occasion. Bird control efforts are focused almost entirely against gulls from late spring to the early fall. The main runway is patrolled and any gulls present are frightened away with pyrotechnics. The first patrol is conducted at about 08:00 when the airport opens. At some times, gulls are persistent and are difficult to scare away. At these times, a shotgun with live ammunition is used to kill one or two gulls to reinforce the scaring effect of the pyrotechnics. The Airport Manager stated that gulls would be killed in a typical year although no gulls were shot in Mr. Stirling believed that most of the gulls that used the airport were Ring-billed Gulls. This conclusion was based primarily on examination of the gulls that were shot and on sight records. It is possible that some Herring Gulls also frequented the airport on occasion. However, it is far more typical to find Ring-billed Gulls using this type of habitat in Ontario. The birds at the airport fed in the apron areas with short grass or loafed on the runway itself (pers. obs.). When gulls were present on the airport, their numbers were usually quite small (10-15) although numbers increased when larger flocks were attracted by the mowing of grass, which exposed various insects and mice. This is behaviour that is typical of Ring-billed Gulls. Mr. Stirling stated that the Transport Canada strike data underestimated the actual number of bird strikes at Muskoka Airport. He thought that the number of strikes averaged 2-3 per year during the six years that he had worked at the airport. He estimated that the strike rate was about 1.3 per 10,000 aircraft movements in the past year or two. This rate is relatively low compared to some airports in Canada. Mr. Stirling stated that he could not discern any regular directional patterns of gull arrival and departure at the airport. When frightened away gulls tended to leave the airport site over the boundary that was closest to the location from which the gulls were frightened. He thought that there was a tendency for gulls to leave the site heading to the south but it was not known where those birds flew to. In addition, frightened gulls often flew off to the west, over Highway 11, toward Lake Muskoka. The Airport Manager stated that vultures did not occur on the ground at the airport. Only small numbers of starlings and blackbirds frequented the site with average flock size of a few birds, perhaps 5-10 birds. These are much smaller flocks than occur K-10

14 commonly in agricultural areas. American Crows occurred on the airport in small flocks (5-15) on occasion but were not a problem for aircraft. Source of Gulls at Airport Airport Manager Stirling noted that his observations did not indicate that the gulls that frequented the airport were associated with the Rosewarne Drive Landfill. This observation was confirmed by the fact that virtually all of the gulls at the airport were Ring-billed Gulls and most of the gulls frequenting Muskoka Landfills were Herring Gulls. Therefore, it is likely that the existing low-level gull problem at the Muskoka Airport is not related to either the Rosewarne Drive or Beiers Road Landfills. Potential Risks to Aviation Safety Associated with Expansion of the Rosewarne Drive Landfill Given the relatively small numbers of hazardous birds likely to use the Rosewarne Drive Landfill expansion in the next 10 years and the distance between the landfill and the airport, it is not expected that a hazard to the safety of aircraft will be created. However, after all of the waste from the District of Muskoka comes to the Rosewarne Drive Landfill in 10 years or so, the numbers of gulls and vultures will increase substantially. However, the level of increase should be reduced with Muskoka s household organics division program fully operational at that time. At that time, it is possible that the increased numbers could create a hazard to aircraft safety, particularly on the gull flight lines along the Muskoka River. To assess that situation, another set of surveys and a related risk assessment should be conducted when the Stisted and Beiers Road landfills are closed. Conclusions and Recommendations It is expected that the operation of the Rosewarne Drive Landfill expansion will not create a hazard to the safety of aircraft using the Muskoka Airport over the next ten years. However, it is recommended that the survey and risk assessment be repeated when the Stisted and Beiers Road Landfills are closed to document the numbers of birds then present at the Rosewarne Drive Landfill and to determine whether a hazard has been created. If there is a hazard, then a number of seasonal control measures are possible that would alleviate the problem. Acknowledgements I thank Mr. Mark Stirling, Manager of the Muskoka Airport for sharing his significant knowledge of the bird situation at the Muskoka Airport. Mr. Bruce MacKinnon, Wildlife Specialist with Transport Canada in Ottawa kindly supplied the bird strike data for the Muskoka Airport. Mr. Jamie Delaney, Manager of Waste Management, District of Muskoka provided data on waste volumes and provided access to the three district K-11

15 landfills. The on-site staff at the Rosewarne Drive, Stisted and Beiers Road landfills kindly provided information on the bird populations using each of the landfills. Karla Kolli, Associate, Dillon Consulting Limited provided background information and was very helpful as the Project Manager for this study. Anne Wright of LGL Limited provided the word-processing for the report. K-12