Bird Impact Study - Comox Strathcona Waste Management Service

Transcription

Bird Impact Assessment
Comox Valley and Campbell River Waste
Management Centres
Prepared for
Comox Strathcona Waste Management
Comox Valley Regional District
600 Comox Road,
Courtenay, BC
V9N 3P6
Prepared by
Dori Manley, RPBio
1310 Marwalk Crescent, Campbell River, BC. V9W 5X1
phone: (250) 287-2462 fax: (250) 287-2452
email: [email protected]
March 2013
Table of Contents
Table of Contents .......................................................................................................... ii
List of Figures .............................................................................................................. iii
List of Tables ................................................................................................................ iv
Glossary of Terms ......................................................................................................... v
Acknowledgements...................................................................................................... vi
1.0
Introduction........................................................................................................ 1
1.1
Project Scope .................................................................................................. 2
1.2
Study Areas ..................................................................................................... 4
1.2.1 Comox Valley Waste Management Centre and Comox Lake ....................... 4
1.2.2 Campbell River Landfill and McIvor Lake ..................................................... 5
2.0
Methods .............................................................................................................. 6
2.1
Landfill Bird Counts .......................................................................................... 6
2.1.1 Active Face Observations ............................................................................ 7
2.1.2 Directional Observations .............................................................................. 7
2.2
Pathogen Risks................................................................................................ 7
2.3
Water Quality ................................................................................................... 8
2.4
Landfill Bird Control Measures ......................................................................... 8
3.0
Results ............................................................................................................... 9
3.1
Bird Counts ...................................................................................................... 9
3.1.1 Active Face ................................................................................................ 11
3.1.2 Directional Observations ............................................................................ 11
3.2
Pathogen Research ....................................................................................... 13
3.3
Water Quality ................................................................................................. 17
3.3.1 Comox Lake ............................................................................................... 17
3.3.2 McIvor Lake ............................................................................................... 20
3.4
Landfill Bird Control Measures ....................................................................... 21
3.4.1 Operational Procedures ............................................................................. 21
3.4.2 Bird Control Measures ............................................................................... 22
3.4.3 Landfill Bird Control Measures Survey ....................................................... 22
4.0
Discussion and Conclusions .......................................................................... 25
5.0
Recommendations........................................................................................... 35
6.0
References ....................................................................................................... 36
Appendix A ..................................................................................................................... I
Appendix B ................................................................................................................... III
Appendix C .................................................................................................................. VI
Appendix D ................................................................................................................. VII
CSWM Bird Impact Assessment Study
ii
List of Figures
Figure 1.
Location of the Comox Valley Waste Management Centre and Comox Lake
within the Comox Valley Regional District. Map Scale 1:50,000. Source:
http://www.imap.rdcs.bc.ca/imap/onpoint ...................................................... 4
Figure 2.
Location of the Campbell River Waste Management Centre and McIvor Lake
on the outskirts of Campbell River, BC. Map Scale 1:20,000. Source
http://webmap.campbellriver.ca/Geocortex_Public/Essentials/Web/Viewer.as
px?Site=CityMap&Reload=true ..................................................................... 5
iii
List of Tables
Table 1.
Bird count data for species groups of interest at the Comox Valley Waste
Management Centre. ..................................................................................... 9
Table 2.
Bird count data for species groups of interest at the Campbell River Waste
Management Centre. ..................................................................................... 9
Table 3.
Historic bird count data for species groups of interest at the Comox Valley
Waste Management Centre. ........................................................................ 10
Table 4.
Historic Bald Eagle counts completed at the Campbell River Waste
Management Centre by volunteers Ed and Thelma Silkens, organized by
Terri Martin and Maj Birch, unpublished data. ............................................. 10
Table 5.
Observations at the active face of the Comox Valley Waste Management
Centre of birds or animals removing solid waste. ........................................ 11
Table 6.
Observations at the active face of the Campbell River Waste Management
Centre of birds or animals removing solid waste. ........................................ 11
Table 7.
Directional observations of bird movement from the Comox Valley Waste
Management Centre towards Comox Lake or from the lake towards the
landfill. ......................................................................................................... 12
Table 8.
Directional observations of bird movement from the Campbell River Waste
Management Centre towards McIvor Lake or from the lake towards the
landfill. ......................................................................................................... 12
Table 9.
Summary of 90th percentiles of E. coli concentrations (CFU/100 ml) for
groups of five samples collected within a 30-day period. Values that exceed
provincial drinking water guidelines are bold. As presented in MOE technical
report on Water Quality Assessment and Objectives for Comox Lake (Epps
and Phippen, 2011). .................................................................................... 18
Table 10. Summary of responses from landfill bird control survey. .............................. 24
Table 11. Summary of issues relating to bird species present at the Comox Valley and
Campbell River Waste Management Centres. ............................................. 32
iv
Glossary of Terms
Active Face - The area of the landfill where material/garbage/refuse is currently being
unloaded and compacted.
Fomite - Any inanimate object or substance capable of carrying infectious organisms,
such as germs, pathogens or parasites, and hence transferring them from one individual
to another. Disposable diapers would be a landfill fomite example.
Vector - Any agent (person, animal or microorganism) that is capable of transmitting an
infectious pathogen from one organism to another. Landfill examples include but are not
limited to flies and other insects, rodents and birds.
Zoonotic Pathogens – Diseases caused by infectious agents that can be transmitted
between animals and humans.
v
Acknowledgements
This study was initiated and coordinated by the Comox Valley Regional District.
Several staff members were directly involved and provided valuable guidance and
assistance. Thank you to Vince Van Tongeren, Jon Isfeld, Jesse Lee and Jennifer
Salutari.
Historic bird data was collected from various sources. Thank you to Art Martell
(Comox Valley Naturalists), Pat Levitt (Comox Valley Naturalists), Dan Bowen (Comox
Valley Naturalists), Shane Tillapaugh (Cumberland Landfill Christmas Bird Count), Luisa
Richardson (Campbell River Christmas Bird Count) and Terri Martin (City of Campbell
River) for sharing data and knowledge of bird numbers at the two regional landfills.
Water quality data and testing results were obtained from several sources and
provided valuable background data for this study. Thank you to the following for your
help: Rosie Barlak (Ministry of Environment), Marc Rutten (Comox Valley Regional
District), Zoe Norcross-Nu’u (Comox Valley Regional District), Allison Neill (City of
Campbell River), Joseph Baratta (VIHA) and Keir Cordner (VIHA).
The University of Victoria were very helpful in sharing their data from Comox Lake
and providing information on Bacterial Source Tracking, which has been collected as
part of their project titled “Climate Impacts and Adaptations for Waterborne Pathogens
and Sustainable Clean and Healthy Water for Communities”. Thank you to Dr. Asit
Mazumder, Sergei Verenitch and Claire Perrin of the Water and Aquatic Sciences
Research Program, UVic.
Several individuals provided valuable feedback to our Landfill Bird Control Survey.
This list includes: Drew Fafard (Hartland Landfill), Helmut Blanken (Nanaimo Regional
Landfill), Kevin Letts (PK Bird Control Services, Nanaimo Regional Landfill), Patrick
Donaghy (7 Mile Landfill), Jon Isfeld (Comox Valley Waste Management Centre), and
Matt Pederson (Berry & Vale, Campbell River Waste Management Centre). Additional
information on bird control services using trained raptors was provided by Gillian
Radcliffe of Pacific Northwest Raptors, who provide services at the Hartland Landfill, and
Kevin Letts of PK Bird Control Services who provide services to the Nanaimo Regional
Landfill.
vi
1.0 Introduction
Comox Strathcona Waste Management (CSWM), a function of the Comox Valley
Regional District (CVRD), is responsible for two regional waste management centres
that serve the Comox Valley and Campbell River. Landfills are attractive sites for birds,
rodents and wildlife as they provide a year round source of food for scavengers. The
CSWM is committed to minimizing the nuisance due to birds at its regional landfill sites
and the potential impact of these birds on adjacent lands and waters. The Comox Valley
Waste Management Centre (Cumberland) and the Campbell River Waste Management
Centre are both located near to waterbodies, Comox Lake and McIvor Lake respectively,
that provide drinking water for local communities. The physical transfer of landfill
material, potential fomites, by birds or animals to areas surrounding the two regional
landfills is of concern due to the possibility of transferring pathogens to humans.
Fomties are any inanimate object or substance capable of carrying infectious organisms,
pathogens or parasites (i.e. disposable diapers). Other potential public health risks
could be birds or animals present at the landfills acting as vectors. A vector is any agent
(person, animal or microorganism) that is capable of transmitting an infectious pathogen
from one organism to another. To examine the potential impacts due to birds or other
vectors on land and waterbodies associated with the two regional landfills, a bird impact
assessment study was initiated. The following objectives were identified:
x
Conduct an assessment of bird species composition and local abundance at
the two regional landfills.
x
Identify vectors present with the potential to transport pathogens from the two
regional landfills to nearby lands and waterbodies.
x
Document the frequency that birds or animals are observed exiting from the
landfill sites with solid waste material to quantify the potential transport of
pathogens via fomites.
x
Identify potential pathogens at each landfill site.
x
Conduct a literature review of these identified pathogens in order to assess
the risk of human exposure to these pathogens.
The combined outcome of these objectives and research assessments will be used to
determine a measure of potential risks present due to bird populations at the two
1
regional waste management centres and to create an index of the potential for these
risks to impact adjacent lands and waterbodies.
In addition to the objectives initially outlined in the request for quotation and project
proposal, information on bird control measures was requested by the Comox Valley
Regional District to guide planning decisions on future bird control methods to be
employed at both the Comox Valley and Campbell River Waste Management Centres.
1.1 Project Scope
Bird counts conducted at the two regional landfills were limited to specific species
groups of interest. These groups were gulls, selected corvids and Bald Eagles
(Haliaeetus leucocephalus). These three species groups were chosen as they are
present in significant numbers at the two regional landfills during the winter and have
been identified as species of concern due to their numbers and their potential to
transport landfill material. All species of gulls were combined into one group for the
purposes of counts. Gull species potentially present at the two landfills include Glaucuswinged Gull (Laurus glaucescens), Mew Gull (Larus canus), Ring-billed Gull (Larus
delawarensis), Herring Gull (Larus argentatus) and Thayer’s Gull (Larus thayeri) with the
most commonly recorded species at the landfills in historic counts being the Glacouswinged Gull. Northwestern Crows (Corvus caurinus) and the Common Raven (Corvus
corax) were the two species of corvids selected to be counted.
Bird counts and observation periods were limited to two visits per site in both the fall
2012 and winter 2013 seasons. The presented data interpretation is limited to these
seasonal observations and comparisons to historic data available for the two regional
landfills.
Determining pathogen transmission pathways is challenging unless done under
strictly controlled laboratory conditions. Wild animals, including birds, are potentially
exposed to many sources of pathogens due to their highly mobile nature. Therefore,
attempting to determine pathways of pathogen transmission through field studies is
complicated by the difficulty in isolating the pathogen point source as well as determining
the mode of transmission. For the purpose of this study, indirect modes of transmission
are considered, including physical transfer of pathogens via feces or via fomites such as
2
landfill material. It is assumed that any material moved from the landfill was a potential
fomite, but no collection or pathogen testing of these materials was completed.
The assessment of potential impacts to nearby waterbodies was limited to impacts to
water quality and pathogen transport relating to birds and/or wildlife. It does not include
impacts due to landfill leachate. No new water quality testing was performed as part of
this study. Existing water quality testing using fecal indicator bacteria levels were
selected for this study as resource managers commonly use these indicators to assess
risk of microbiological contamination from fecal matter (Field and Samadpour, 2007; Ishii
and Sadowsky, 2008). To assess the microbiological quality of water in Comox Lake
and McIvor Lake Escherichia coli results were researched as this coliform is considered
to be specifically of fecal origin (Yates, 2007). The risk of using coliforms as a surrogate
for pathogenic microorganisms is that there are differences between them and as a
result there have been disease outbreaks when indicator bacteria counts are at
acceptable levels (Yates, 2007; Haack et al., 2009). Data sourcing also included
research for any available testing on pathogenic microorganisms such as Giardia or
Cryptosporidium, but these results were very limited in availability.
3
1.2 Study Areas
1.2.1
Comox Valley Waste Management Centre and Comox Lake
The Comox Valley Waste Management Centre (CVWMC) is located near to the
Village of Cumberland approximately 1 km east of Comox Lake, which is the drinking
water supply for Courtenay/Comox (Figure 1). Current disposal estimates for the centre
are 38,445 tonnes per year (AECOM, 2012). Comox Lake has a high level of
recreational use including swimming, boating, fishing and camping as well as being a
controlled reservoir for hydroelectric generation. There are 77 cabins located around
Comox Lake, 70 of which are used seasonally, while the remaining seven are used year
round (Epps and Phippen, 2011). The Fish and Game Club campground, Cumberland
campground and all seven year round use cabins are located on the perimeter of the
eastern portions of the lake, which is closest to the CVWMC. The largest land use within
the Comox Lake watershed is active forestry management at 60.84% of the total
watershed area (Benjamin and Vasarhelyi, 2006).
CVWMC
Comox Lake
Village of
Cumberland
Figure 1. Location of the Comox Valley Waste Management Centre and Comox Lake
within the Comox Valley Regional District. Map Scale 1:50,000. Source:
http://www.imap.rdcs.bc.ca/imap/onpoint
4
1.2.2
Campbell River Landfill and McIvor Lake
The Campbell River Waste Management Centre (CRWMC) is located on the outskirts
of Campbell River approximately 500 m east of McIvor Lake at its closest point (Figure
2). Current disposal estimates for the centre are 24,921 tonnes per year (AECOM,
2012). McIvor Lake has high recreational values (fishing, swimming and boating), is
surrounded by several residential properties, is part of a controlled reservoir system for
hydroelectric generation and is part of the drinking water source for the City of Campbell
River. The largest land owner within the Campbell River watershed is Provincial Parks
with a total of 66.52% of the total watershed area (Dayton and Knight Ltd., 2001).
Ladore Dam
CRWMC
Argonaut
Road
McIvor Lake
Figure 2. Location of the Campbell River Waste Management Centre and McIvor Lake
on the outskirts of Campbell River, BC. Map Scale 1:20,000. Source
http://webmap.campbellriver.ca/Geocortex_Public/Essentials/Web/Viewer.aspx
?Site=CityMap&Reload=true
5
2.0 Methods
A summary of the methods used for the Comox Strathcona Waste Management bird
impact assessment study in the fall and winter of 2012/2013 is presented in the following
sections.
2.1 Landfill Bird Counts
Discussions with landfill managers at both the Comox Valley and Campbell River
Waste Management Centres indicated that bird numbers and species composition at the
landfills varied throughout the year with the peak being during the winter months. Due to
contract timing and budgets, observations were limited to two seasons, fall and winter.
Two site visits were completed at both the Comox Valley and Campbell River Waste
Management Centres in fall 2012 and winter 2013.
Total counts of the species groups of interest (gulls, selected corvids and Bald
Eagles) present were tallied during each site visit. Observers moved throughout the
landfill in order to count all individuals from the species groups of interest that were
present on the site. Birds present on the perimeter of the site were included, but in the
case of the CRWMC, Argonaut Road was used as the boundary of the site and no birds
present on the south side of the road were included in the tallies. Observers waited for
the majority of birds to be settled (not in flight) in order to get the most accurate counts
possible.
Fall counts were performed by one observer and individual birds were counted and
tallied. Winter counts were completed by two observers using block count methods for
counting gulls, as their numbers were too high to be counted individually. Observers
determined what a group of either 50 or 100 gulls looked like and then tallied similar
blocks to determine a total count. Each observer completed a count and then results
were compared between the two. If the numbers were consistent that number was
recorded but if there was a large discrepancy the area was recounted.
Any wildlife observed at each site was recorded in order to identify all potential
vectors of pathogen transport.
Historic bird count data from the two regional landfills was collected through sources
such as the Comox Valley Naturalists, Christmas Bird Counts and Bald Eagle counts.
6
2.1.1
Active Face Observations
In order to quantify the potential transport of pathogens via fomites, a 30 minute
observation period was completed during each site visit to directly observe the active
face and watch for birds or animals removing solid waste material from this area. In
order for an occurrence to be tallied the bird or animal had to be observed removing
material that could act as a fomite from the active face to another area of the site.
Observations were tallied by species group and recorded.
2.1.2
Directional Observations
In order to quantify the potential occurrence of pathogen transport via vectors from
the landfills to adjacent waterbodies, directional observations were completed to
document the frequency with which vectors moved from the landfills towards the
associated waterbody. During each site visit a thirty minute observation period was
completed where observers watched for movement of birds or other vectors to and from
the landfill in the direction of the nearby waterbodies. In Campbell River observers
positioned themselves to observe and count any vectors moving towards McIvor Lake,
which is located to the west of the site. At the CVWMC observers positioned themselves
to observe and count any vectors moving towards Comox Lake, which is located to the
west of the site. Birds were counted only if their movement in this direction or from this
direction was observed to be from a distance and not associated with movement within
the site or to the surrounding perimeter. Observations were tallied by species of interest
groups and by direction either towards the landfill or towards the lake. During these
observation periods, observers also recorded any instances of birds or animals
physically transporting fomites (landfill material) in the direction of nearby waterbodies.
2.2 Pathogen Risks
Pathogen risk was determined through literature reviews to identify what pathogens
may be present at the landfill as well as which pathogens may be transported by vectors
from the landfill to nearby lands and waterbodies. Research was conducted on the
viability of pathogens via transport vectors, as well as the risk of these pathogens to
human health.
7
2.3 Water Quality
Available sources of background and historic water quality data were collected
through the Vancouver Island Health Authority (VIHA), City of Campbell River, Comox
Valley Regional District, University of Victoria, and the Ministry of Environment. Data
collection focussed on fecal contaminant indicators such as fecal coliform and E. coli
testing as well as any testing available for pathogenic microorganisms from raw water
sources from both Comox Lake and McIvor Lake. No water quality sampling or testing
was completed as part of this study. The collected data was summarized and presented
along with discussion on how it relates to existing water quality guidelines.
2.4 Landfill Bird Control Measures
A Landfill Bird Control Measures survey was created and distributed to landfill
operators on Vancouver Island including: Patrick Donaghy (7 Mile Landfill, Port McNeill),
Berry and Vale (Campbell River, Port Alberni and Uculet Landfills), Jon Isfeld (Comox
Valley), Helmut Blanken (Nanaimo Regional Landfill) and Drew Fafard (Hartland
Regional Landfill, Victoria). A copy of the survey is included in Appendix A. Results of
the surveys were collected and if necessary additional clarification of responses was
requested. Responses were summarized and presented along with additional
information on bird control measures collected through literature review and interviews.
8
3.0 Results
Results of observations, data collection and background research for the Comox
Strathcona Waste Management bird impact assessment study are presented below.
Photographs taken during site visits are presented in Appendix B.
3.1
Bird Counts
Bird counts conducted at the two regional landfills operated by Comox Strathcona
Waste Management confirmed the seasonal variation in species and numbers that were
indicated by landfill managers and operators (Table 1 and 2). Gull species were present
during both the fall and winter seasons and increased at both sites during the winter with
the largest increases noted at the CVWMC (Photo 1, 2, 3 and 4). Corvids were present
at both sites during both seasons with significant increases noted during the winter at
both sites. Bald Eagles were scarce in the fall but significant numbers were counted
during the winter season at both sites (Photo 5 and 6).
Table 1.
Bird count data for species groups of interest at the Comox Valley Waste
Management Centre.
Season
Fall
Fall
Winter
Winter
Table 2.
Date
Sept. 12, 2012
Oct. 2, 2012
Jan. 8, 2013
Jan. 22, 2013
Gulls
240
1160
3435
3655
Corvids
19
56
138
121
Bald Eagles
0
0
232
381
Bird count data for species groups of interest at the Campbell River Waste
Management Centre.
Season
Fall
Fall
Winter
Winter
Date
Sept. 5, 2012
Sept. 26, 2012
Jan. 9, 2013
Jan. 23, 2013
Gulls
166
300
490
1035
Corvids
30
43
177
125
Bald Eagles
2
0
286
187
Historic bird count data was collected from various sources where available. Existing
Christmas Bird Count data was only included where numbers were recorded specifically
for a landfill. Data from these counts are typically tallied through a count circle so often
recorded numbers include birds from various habitats. For example the count circle that
includes the CRWMC begins at the Campbell River estuary. As gulls and eagles could
be present in both habitat types it is impossible to separate landfill numbers from the
recorded totals. The Comox Valley Naturalists have completed spring bird counts at the
9
CVWMC as well as a February Bald Eagle count (Table 3). Historic data available for
the CVWMC shows similar species composition and numbers in the winter season as
observed during counts completed for this study. Spring counts indicate that the winter
peak in bird numbers does not extend into May.
Table 3.
Historic bird count data for species groups of interest at the Comox Valley
Waste Management Centre.
Season
Date
Gulls
Corvids
Bald
Eagles
Winter
Feb. 28, 2009
-
-
137
Spring
May 2, 2010
121
25
40
Spring
May 1, 2011
252
25
22
Winter
Dec. 2012
1778
147
124
Comments/Source
Bald Eagle count/Comox
Valley Naturalists
Spring Bird Count/Comox
Valley Naturalists
Spring Bird Count/Comox
Valley Naturalists
Christmas Bird Count/Comox
Valley Naturalists
An existing study on trends in bird populations in the Comox Valley examined
changes in numbers of birds from 1976 to 2006 based on counts conducted in May and
December following the Christmas Bird Count circle. The results of this analysis indicate
that Bald Eagles have shown significant, steady increase in numbers in both the winter
and spring counts, Glaucous-winged Gulls have shown a significant increase in winter
numbers, and the Northwestern Crow has shown a significant decrease in winter
numbers (Martell, 2008). These trends are for the Comox Valley, not specifically the
CVWMC, but they provide a reference as to what the trend in population numbers is for
these species in the Comox Valley.
The only bird count data available that was specific to the CRWMC was winter Bald
Eagle counts (Table 4). The CRWMC eagle data confirms the significant number of Bald
Eagles present at the site during the winter months.
Table 4.
Historic Bald Eagle counts completed at the Campbell River Waste
Management Centre by volunteers Ed and Thelma Silkens, organized by
Terri Martin and Maj Birch, unpublished data.
Season
Winter
Winter
Winter
Winter
Winter
Date
March 4, 2006
Feb. 25, 2007
Feb. 24, 2008
Feb. 28, 2009
Feb. 27, 2010
Bald Eagles
50
69
121
186
55
Comments/Source
Terri Martin
Terri Martin
Terri Martin
Terri Martin
Terri Martin
10
3.1.1
Active Face
Observations at the active face identified corvids and Bald Eagles as being the only
birds or vector that moved solid waste material away from the active face (Table 5 and
6). Gulls were commonly observed feeding on solid waste within the active face and
also observed flying with material in their beaks but they remained within the active face
area. In all occurrences of fomite removal from the active face at both landfills, corvids
and eagles took solid waste from the active face to the tree edges present either within
the landfill boundaries or on the perimeter of the sites. Birds were not observed moving
to adjacent lands or towards nearby waterbodies with solid waste material. There is
evidence of large amounts of plastic hanging from trees on the perimeter of both sites,
probably transported by corvids or eagles (Photo 6). The removal of fomites from the
active face was more commonly observed during the winter months at both sites likely
due to the significant increases in corvids and the arrival of Bald Eagles during this
season. No other birds or animals were observed removing material from the active face
during the observation periods at either site.
Table 5.
Observations at the active face of the Comox Valley Waste Management
Centre of birds or animals removing solid waste.
Season
Fall
Fall
Winter
Winter
Table 6.
Gulls
0
0
0
0
Corvids
0
0
37
43
Bald Eagles
0
0
2
1
Other
0
0
0
0
Observations at the active face of the Campbell River Waste Management
Centre of birds or animals removing solid waste.
Season
Fall
Fall
Winter
Winter
3.1.2
Date
Sept. 12, 2012
Oct. 2, 2012
Jan. 8, 2013
Jan. 22, 2013
Date
Sept. 5, 2012
Sept. 26, 2012
Jan. 9, 2013
Jan. 23, 2013
Gulls
0
0
0
0
Corvids
2
3
20
44
Bald Eagles
0
0
5
0
Other
0
0
0
0
Directional Observations
Directional observations at each waste management site confirmed the movement of
landfill birds in the general direction of Comox Lake from the CVWMC (Table 7) and
towards McIvor Lake from the CRWMC (Table 8). Gulls were the most commonly
observed group using this movement pathway, while some corvids were observed but no
eagles were recorded. No observations were completed at either of these lakes to
11
confirm that bird species common to the landfills were present but observations showed
a movement pathway in those general directions. Residents of McIvor Lake have
confirmed that gulls are present in the hundreds in the bay closest to the CRWMC during
the winter months (Ferron, J. pers.comm., 2013). Bacterial source tracking completed in
Comox Lake has confirmed that gulls are contributing fecal matter to Comox Lake (UVic,
2012; Clayton, 2005). No other vectors were observed moving between the waste
management centres and their associated lakes during these observation periods.
Table 7.
Directional observations of bird movement from the Comox Valley Waste
Management Centre towards Comox Lake or from the lake towards the
landfill.
Season
Date
Fall
Fall
Winter
Winter
Sept. 12, 2012
Oct. 2, 2012
Jan. 8, 2013
Jan. 22, 2013
Table 8.
Towards Comox Lake from
CVWMC
Bald
Gulls Corvids
Eagles
144
0
0
299
1
0
1668
0
0
541
0
0
Towards CVWMC from Comox
Lake
Bald
Gulls
Corvids
Eagles
43
0
0
479
3
0
735
0
0
417
0
0
Directional observations of bird movement from the Campbell River Waste
Management Centre towards McIvor Lake or from the lake towards the
landfill.
Season
Date
Fall
Fall
Winter
Winter
Sept. 5, 2012
Sept. 26, 2012
Jan. 9, 2013
Jan. 23, 2013
Towards McIvor Lake from
CVWMC
Bald
Gulls Corvids
Eagles
0
0
0
57
23
0
67
4
0
3
0
0
Towards CVWMC from McIvor
Lake
Bald
Gulls
Corvids
Eagles
9
3
0
39
4
0
96
0
0
2
0
0
The frequency that gull movement was recorded does not appear to be correlated
with the numbers of gulls present at each site or the season. Movement was recorded in
both the fall and winter seasons at both landfills but there was a high degree of variability
between observations within each season and relative to bird count data. Counts were
generally performed at the same time of day however, weather may be influencing
movement behaviour. Movement of gulls has been confirmed between the two waste
management centres and Comox Lake and McIvor Lake during both the fall and winter
seasons.
12
During these observation periods observers watched for the transport of fomites from
the landfill in the direction of Comox Lake or McIvor Lake. There were no observations
of birds transporting landfill material from the site in the direction of the lakes from either
waste management centre during fall or winter. Background research identified that
residents of McIvor Lake have observed landfill solid waste material at McIvor Lake
(Ferron, J. pers.comm., 2013, and McCubbing, 1983 and 1988). These two residents
indicate that landfill items transported to the lake include rubber gloves, plastic bags,
plastic toys and other bits of debris and garbage. No references of this occurring in
Comox Lake were identified but interviews with lake residents were not completed during
this study.
Site visits, bird counts, active face observations and directional observations identified
Bald Eagles, Northwestern Crows and Common Ravens as the only birds or animals
observed moving fomites from either the Comox Valley or the Campbell River Waste
Management Centres (Tables 5, 6, 7 and 8). Observations identified gulls, Northwestern
Crows and Common Ravens as vectors through the potential transport of pathogens via
fecal matter to both McIvor Lake and Comox Lake (Tables 5, 6, 7 and 8). The only other
wildlife observed at either site were deer at the yard waste composting area of the
CVWMC. This area is not considered a pathogen source and deer were not observed
within the active area of the landfill therefore they are not considered to be a risk for
transporting pathogenic materials to adjacent lands or waterbodies. Existing electrified
fencing at both the CVWMC and CRWMC has been effective in controlling wildlife
access to these sites. Interviews with site operators indicate that there have been no
recent problems with bears, rodents or racoons at either site.
3.2 Pathogen Research
In order to understand the risk of pathogen transport from landfills, background on
landfill operations is necessary to provide an overview of the materials present on site
that could act as pathogen sources. Biomedical waste and hazardous wastes are
prohibited at both the Campbell River and Comox Valley Waste Management Centres
under Bylaw 1701 and the Landfill Criteria for Municipal Solid Waste (MOE, 1993).
Acceptance of dead animals, fish hatchery and farming wastes must be approved by the
1
Comox Valley Regional District Bylaw 170. Solid Waste fees and charges, 2011 –
CONSOLIDATED. Schedule ‘B’ – Prohibited Waste.
13
landfill manager and require immediate burial and cover in dedicated locations (MOE,
1993). The same policy applies to ashes or sharps received from veterinary clinics.
Specified portions of cow carcasses (items defined as Specific Risk Material – skull,
brain, eyes, etc.) are not accepted due to mad cow disease. The CVWMC produces a
soil amendment called SkyRocket, which is the product of composting biosolids derived
from human wastewater treatment with wood chips. The area where composting of
biosolids occurs at the CVWMC is not an area where gulls, corvids or eagles were
observed to be feeding. This potential source of human pathogenic material does not
appear to be at risk to be transported to adjacent lands or waterbodies but should
continue to be monitored. The potential pathogenic source material present at the two
regional landfills is limited to food waste, human waste from disposable diapers and pet
waste.
Research on pathogenic microorganisms was conducted in order to identify potential
risks present at the two regional landfills and those pathogens that could potentially be
transferred to nearby lands and waterbodies by vectors or fomites. No pathogen testing
has been completed at either of the waste management centres but background
research identified that fecal coliforms, bacterial pathogens, human enteroviruses,
human noroviruses and protozoan parasites are found in municipal solid waste (Gerba et
al., 2011). Study observations indicated that fomite movement was limited to the
perimeter of the landfill sites resulting in limited risk to humans due to the lack of a
transmission pathway (i.e. ingestion or immersion). Pathogen research focussed on
waterborne pathogenic microorganisms as study observations and research results
confirmed that gulls present at the two regional landfills frequent nearby waterbodies.
Enteric pathogenic bacteria occur in water as a result of contamination with human or
animal fecal wastes. Enteric protozoa are common parasites that are also present in
water as a result of human and animal fecal contamination. A literature review
completed on avian impact to recreational water quality was unable to locate any
published studies that found or investigated human pathogenic viruses present in gulls
or gull fecal material (Kleinheinz and Busse, 2010). A summary of waterborne
pathogens that could potentially be present at the two landfills and transported by birds
either via fomites or through fecal matter is presented in the following paragraphs and
discussed in relation to their risks to humans.
14
Campylobacter
Campylobacter species are enteric pathogenic bacteria that are predominantly
considered to be zoonotic pathogens (Fricker, 2006) causing gastrointestinal enteritis.
The organisms are harboured in the intestinal tract of a wide range of domestic and wild
animals, particularly birds. It is likely that a significant proportion of seagulls also carry
these organisms (Moore et al., 2002; Pond, 2005). The number of infections in humans
tends to portray seasonal variation with a peak in the warmer months (July-October) of
the year, suggesting that illness may be related to seasonal exposures (Broman et al.,
2002). There have been no recorded instances of Campylobacter-associated illness as
a result of recreational water activity in North America and no outbreaks of
campylobacteriosis have been recorded in Canadian recreational water (Health Canada,
2012). The most notable Canadian waterborne outbreak involving Campylobacter
occurred in Walkerton, Ontario, in May 2000 (Clark et al., 2003). This outbreak was
linked to fecally contaminated well water that was not properly treated. Studies have
shown no correlation between indicator organisms (e.g. E. coli) and the presence of
Campylobacter in raw surface water supplies (Carter et al., 1987). Thus, current
recreation water quality monitoring of coliforms may not be adequate indicators of the
presence of C. jejuni resulting in a risk of exposure to Campylobacter bacteria in Comox
Lake and McIvor Lake. The risk associated with this bacteria contaminating drinking
water is unknown as there is no testing done for this bacteria and existing monitoring of
drinking water using fecal indicators may not identify the presence of this pathogen. The
movement of birds from the two regional landfills to Comox Lake and McIvor Lake could
be a source of Campylobacter bacteria through fecal contamination of lake water.
Pathogenic E. coli
The vast majority of the E. coli isolates are harmless but there are several strains that
act as human pathogens. Human sewage is the principal source of all the major
pathogenic E. coli groups with the exception of one strain for which cattle are considered
to be the primary reservoir as well as human wastes (Health Canada, 2012). Seagulls
and birds are not considered a source of pathogenic E. coli. Birds and other animals
could potentially be exposed to pathogenic E. coli in human waste through diapers at the
landfills but transfer of this pathogen to nearby lands and waterbodies via birds is
unlikely. As E. coli is routinely monitored within Comox Lake this pathogen is not
considered a risk unless elevated testing results are observed. E. coli sampling is not
completed in McIvor Lake, although sampling at Ladore Dam should be representative.
15
Water quality results from Ladore Dam have not exceeded provincial drinking water
guidelines or Canadian recreational water quality guidelines for primary contact
activities. As E. coli levels are monitored for recreation uses and in drinking water, E.
coli contamination does not appear to be a risk to humans using or consuming water
from Comox Lake or McIvor Lake unless elevated levels are detected through water
quality monitoring.
Salmonella
Salmonella are considered zoonotic pathogens with birds being a potential reservoir
(Percival et al., 2004). Gastroenteritis represents the most commonly encountered type
of Salmonella-associated illness. Approximately 200 strains of Salmonella spp. were
isolated from gull droppings in a study conducted on Ring-billed Gulls, including seven
that are pathogenic to humans (Levesque et al., 1993). There have been no recorded
outbreaks from Salmonella as a result of recreational water activity in North America
(Health Canada, 2012). Numerous Salmonella outbreaks linked to contaminated
drinking water have been reported caused by either untreated or improperly treated
drinking water (Health Canada, 2006). Salmonella could be a risk to recreation users of
lake water as testing for this pathogen is not completed in Comox Lake or McIvor Lake
and current water quality monitoring for recreation activities using coliforms may not
identify the presence of this pathogen. The risk of Salmonella contaminating drinking
water is unknown as there is no testing done for this bacteria and existing monitoring of
drinking water using fecal indicators may not identify the presence of this pathogen. The
movement of birds from the two regional landfills to Comox Lake and McIvor Lake could
be a source of Salmonella through fecal contamination of lake water.
Giardia
One species of Giardia, an enteric protozoa, is the only human-infective species. It is
found in humans and a wide range of other mammals. Other species of Giardia have
been reported in rodents and birds but they are not considered a risk to humans.
Infection occurs through ingestion of environmentally resistant cysts. In theory, a single
cyst is sufficient to cause human infection, however, studies have shown that the dose
required to cause infection is usually greater (Health Canada, 2012). Birds and animals
could potentially be exposed to Giardia in human wastes through diapers at the landfills
but transfer of this pathogen to adjacent lands and waterbodies is unlikely.
16
Cryptosporidium
Cryptosporidium oocysts, which cause the gastrointestinal disease cryptosporidiosis,
are commonly found in water affected by human or livestock wastes (Health Canada,
2004). Humans and cattle are the most significant sources of Cryptosporidium while
birds are not listed as a reservoir or significant source (Health Canada, 2012). For
Cryptosporidium, a variety of median infective doses have been reported although, as is
the case with other pathogens, a single organism is theoretically sufficient to initiate
infection (Health Canada, 2012). It is suggested that waterfowl and therefore perhaps
gulls, may be capable of picking up oocysts from their habitat and depositing them
elsewhere through fecal discharge. There is little risk of landfill birds transporting
Cryptosporidium to either Comox Lake or McIvor Lake due to the limited exposure to
sources of this pathogen at the two regional landfills.
3.3 Water Quality
In an effort to identify potential impacts to nearby waterbodies due to fecal
contamination caused by birds, background water quality data was collected for both
lakes associated with the two regional landfills. Data sourcing was focused on E. coli as
it is specifically of fecal origin and is the best available surrogate for predicting the
presence of enteric pathogenic microorganisms. The presence of E. coli is expected to
indicate the possible presence of these organisms however the absence should not be
interpreted to mean that all pathogenic microorganisms are also absent (Health Canada,
2012). There are many challenges associated with the detection of pathogenic
microorganisms limiting the available data to sampling for Giardia and Cryptosporidium
in John Hart Lake only. Existing water quality data is presented below for each site.
3.3.1
Comox Lake
Water quality results for Comox Lake were provided by various sources including the
Ministry of Environment, the Vancouver Island Health Authority and the University of
Victoria.
The Ministry of Environment completed a water quality assessment of Comox Lake in
order to establish water quality objectives designed to protect existing and future water
uses (Epps and Phippen, 2011). Water quality monitoring was conducted between 2005
and 2008. Bacteriological samples were collected during summer low flow and fall flush
periods with shoreline stations selected in areas closest to cabins and campgrounds as
17
well as in areas habituated by waterfowl, as these were the areas most likely to have the
highest coliform concentrations.
Four microbiological sampling stations were located in the outlet basin of Comox
Lake, which is the area closest to the CVWMC. General results indicated that the lake is
oligotrophic and the overall state of the water quality is very good (Epps and Phippen,
2011). Concentrations of E. coli were substantially lower in the inlet basin of Comox
Lake than at the outlet basin, indicating that E. coli levels are likely reflective of
background levels and that the water quality within the eastern portions of the lake is
influenced by recreational uses or external influences. Primary contact recreation
guidelines for fecal coliforms and E. coli were not exceeded at any of the sampling sites.
However, occasional elevated values of both fecal coliforms and E. coli were observed,
especially in the outlet basin. Possible contamination from hubs of activity including
campgrounds and boat launches, as well as cabins, pet, waterfowl and wildlife could all
be contributing (Epps and Phippen, 2011). E. coli results from the outlet basin exceeded
BC MOE drinking water guidelines of 10 CFU/100 mL (Warrington, 2001) on 12 out of 24
sampling periods (Table 9, Epps and Phippen, 2011). In both instances where
bacteriological numbers were significantly elevated (at sites 4 and 6), high numbers of
birds (generally seagulls) were observed at and near the sampling stations indicating a
potential source (Epps and Phippen, 2011). A microbial source tracking study prepared
for the Comox Strathcona Regional District in 2005 found that the predominant sources
of fecal coliforms near the Comox Lake outlet were attributable to deer, dogs and
seagulls (Clayton, 2005).
Table 9.
Summary of 90th percentiles of E. coli concentrations (CFU/100 ml) for groups
of five samples collected within a 30-day period. Values that exceed
provincial drinking water guidelines are bold. As presented in MOE technical
report on Water Quality Assessment and Objectives for Comox Lake (Epps
and Phippen, 2011).
Location
Site
#
Inlet
Inlet
Inlet
Outlet
Outlet
Outlet
Outlet
1
2
3
4
5
6
7
Aug. 11Sept. 9,
2005
<1
<1
<1
<1
3.8
<1.0
1.0
Oct. 14Nov. 10,
2005
1.6
8.2
2.2
6.6
4.0
3.6
38.6
Aug. 30Sept. 13,
2006
<1
<1
<1
2.0
10.4
6.2
44.2
Oct. 17Nov. 22,
2006
3.6
3.8
2.8
23.2
12.6
3.8
2.6
Aug. 9Sept. 13,
2007
5.8
16.4
4.0
41.6
23.6
142.4
17.0
Oct. 23Nov. 22,
2007
4.2
2.2
2.2
88.4
5.0
20.0
20.6
18
The University of Victoria, in conjunction with the CVRD, is collecting data from
Comox Lake as part of a long term study on climate change relating to sustainable clean
and healthy water (UVic, 2012). The data they have collected includes water quality
testing for E. coli from Comox Lake and further bacterial source tracking when E. coli is
detected. Up to five fingerprints are isolated from confirmed E. coli samples, although
more or less may be present in each sample. These fingerprints are compared to a
source library and if the probability of the fingerprint belonging to an animal in the source
library is greater than 80% the bacteria is identified as coming from that source. The
animal source library that UVic is using includes gulls but not crows, ravens or Bald
Eagles. Results do not identify all possible sources of fecal contamination as not all
available fingerprints in a sample are selected for analysis but data is representative of
contamination sources and their relative frequencies. Of the 431 samples collected from
Comox Lake or the Intake Station (the two sample locations potentially impacted by birds
from CVWMC) 219 contained detectable amounts of E. coli which were analyzed for
bacteria source fingerprints. Gull species were identified as at least one of the bacterial
sources for 49 samples, or 11%. Humans were the most commonly identified bacteria
source (85 samples, 19%), followed by black bear (69 samples, 16%), and dogs were
the bacterial source in 22 samples (5%) (Appendix C).
The UVic database used for analysis includes data from Sept. 10, 2010 to November
5, 2012, with sampling occurring in every month. Of the 49 samples where gulls were
identified as the bacterial source, 29 were collected in 2010, 16 in 2011 and only four in
2012. Gulls were identified as the bacterial sources in each of the months of the year
but the majority, 33 of 49 occurrences, were in the winter months (October to April) when
gull numbers are highest at the CVWMC. Most of the occurrences were from water
samples collected from within Comox Lake (30), while an additional 19 samples
identifying gulls as the bacterial source were collected from the penstock at the
chlorination station.
Vancouver Island Health Authority completes beach sampling at three locations in
Comox Lake to monitor water quality for the protection of recreational users during the
summer months, usually June, July, August and September. Sampling results for fecal
coliforms exceeded the guideline for Canadian recreational water quality for primary
contact activities of ≤400 CFU/100ml (Health Canada, 2012) on three different occasions
all within the month of August. On August 17 of both 2009 and 2010 samples from the
19
beach in the east portion of Comox Lake exceeded guidelines, while on August 25, 2010
the west beach was out of compliance. Re-sampling during these events showed that
levels were within guidelines and no public advisories were issues. No beach closures
have been required at Comox Lake due to water quality issues (Cordner, K.,
pers.comm., 2013)
3.3.2
McIvor Lake
Water quality results for McIvor Lake were provided by various sources including the
Ministry of Environment, The City of Campbell River and the Vancouver Island Health
Authority.
The Ministry of Environment completed a water quality assessment of John Hart Lake
and McIvor Lake in order to establish water quality objectives designed to protect
existing and future water uses (Barlak and Phippen, 2012). Water quality monitoring
was conducted in summer low flow and fall flush periods between 2003 and 2006.
General results indicate that the lake is oligotrophic and that the overall state of the
water quality is very good (Barlak and Phippen, 2012). Microbiological samples were
only collected within John Hart Lake, but samples collected at Ladore Dam, the McIvor
Lake outlet, are presented as they would be the most representative of conditions in
McIvor Lake. Testing results showed that E. coli concentrations ranged from below
detection limits (<1 CFU/100 ml) to 2.0 CFU/100 ml for the 17 samples collected at
Ladore Dam with the highest values detected in August and September, (when bird
numbers at the CRWMC are reported to be lowest). MOE determined that
bacteriological results for John Hart Lake were relatively low and are reflective of natural
or background conditions (Barlak and Phippen, 2012). The drinking water guidelines for
fecal coliforms and E. coli were not exceeded at either of the sampling sites when
requisite sampling frequency was sufficient to determine compliance. However,
occasional elevated values of both fecal coliforms and E. coli were seen at the Ladore
Dam site on John Hart Lake, likely due to higher recreational use, bird use and higher
residential density within McIvor Lake (Barlak and Phippen, 2012). The report outlines a
risk to water quality in McIvor Lake from gulls that have fed at the Campbell River landfill
then moved to McIvor Lake while transporting landfill solid waste material (Brunn, J.,
pers.comm., 2010). These movements could cause contamination from solid waste and
elevated fecal coliforms from gull excrement (Barlak and Phippen, 2012).
20
The City of Campbell River has completed sampling for enteric protozoa, Giardia and
Cryptosporidium, in John Hart Lake. Testing results from 2011 and 2012 had no
detections of Cryptosporidium from 20 samples collected in August, November and May.
Testing for Giardia over the same time period and frequency had a detection of 1
cyst/100ml in the northwest corner of John Hart Lake at a depth of 10m on November
20, 2012. A health hazard exists if these protozoa are found in any 100 ml sample of
raw water (Warrington, 1988).
Vancouver Island Health Authority completes beach sampling at three locations in
McIvor Lake to monitor water quality for the protection of recreational users during the
summer months, usually June, July, August and September. Recorded results since
2002 have never exceeded the guideline for Canadian recreational water quality for
primary contact activities of ≤400 CFU/100ml (Health Canada, 2012) and no beach
closures have ever been necessary within McIvor Lake due to water quality issues
(Baratta, J., pers.comm., 2013).
3.4 Landfill Bird Control Measures
There is little that can be done to control wildlife or bird movement. What can be
done is to reduce the attractiveness of landfills to wildlife and birds thereby reducing the
chances of vectors acquiring and spreading pathogens. Bird control measures are
employed at both the Comox Valley and Campbell River Waste Management Centres
not only to minimize the nuisance that these birds can have on site, but also to minimize
their impact on surrounding lands and waterbodies.
3.4.1
Operational Procedures
The Ministry of Environment created landfill criteria for municipal solid waste
management that were developed following the introduction of the Waste Management
Act in 1993 and set operational requirements for existing landfills (MOE, 1993).
Highlights from this document relating to bird and or wildlife control, and general landfill
operations include:
x
The working face area should be minimized as much as possible.
x
Cover material is to be applied at all sanitary landfills at the end of each day
or operation. Where a Sanitary Landfill operates continuously 24 hours per
21
day, 0.15 m of cover material is to be applied at a frequency approved by the
Manager.
x
Vectors are to be controlled by the application of cover material at a specified
frequency or by other control measures as required and approved by the
manager.
x
Landfills are to be operated so as to minimize the attraction of wildlife such
as bears and birds by applying cover at required frequencies and instituting a
good housekeeping program. Further control measures, such as bear
control fences and bird control devices, may be specified by the manager.
Adjustments to operational procedures at the Comox Valley and Campbell River
Waste Management Centers have been implemented to help reduce bird populations.
These include utilizing a smaller active face with increased compaction, which has
minimized the area available for birds and animals to scavenge material during
operational hours and covering the active face with steel plates at the end of every
working day (Isfeld, 2011). The use of steel plates eliminates bird access to the food
source after operational hours. Long grass has been planted at both sites to reduce
available loafing areas for birds. These actions have reduced the ability for scavengers
to access the active face and roost on site but there are still large numbers of gulls,
eagles and corvids present at both sites during the winter months.
3.4.2
Bird Control Measures
Specific bird control measures implemented at the both regional landfills have
included a signal pistol with scare cartridges (screecher and bangers), a gas gun
(propane cannon) and recorded distress calls. While these techniques were initially
effective birds quickly became habituated reducing their effectiveness in controlling bird
numbers (Isfeld, 2011).
3.4.3
Landfill Bird Control Measures Survey
Responses to the Landfill Bird Control Measures surveys were collected from landfill
operators throughout Vancouver Island (Table 10, completed surveys are included in
Appendix D). Generally all operators agreed that operational practices such as reducing
the active face and using appropriate cover was an important factor in minimizing bird
access to landfill waste and reducing bird numbers on site. Several respondents
22
indicated that operational measures alone were not adequate to reduce bird numbers on
site, especially during the winter months when bird numbers are the highest. All
respondents have used at least two bird deterrent devices, and most used a combination
of devices. Comments on the effectiveness of each measure in reducing bird numbers
indicated that techniques need to be varied otherwise birds quickly become habituated.
Hartland Landfill in Victoria and the Nanaimo Regional Landfill utilize trained birds of
prey facilitated through bird control officers to reduce bird numbers on site. The
Nanaimo Regional Landfill has one bird control officer on site year-round and add an
additional officer during the winter months when bird numbers are at their peak. They
also use skeets or clay disks and scare crows as secondary bird control measures. The
contractor has reported that their services have reduced gull numbers by 62% (Nanaimo
Regional Landfill Survey, Appendix C). Hartland Landfill employs a bird control officer
only during the winter months (mid-October to May) when gull numbers are the highest.
The trained bird of prey is used in conjunction with screechers during the winter months
and screechers alone are used as bird deterrent during other months of the year.
Hartland Landfill converted from an overhead wire system to the use of trained birds of
prey and are content with this method of bird control. The overhead wire system was
very effective initially but required expensive maintenance, deteriorated quickly, and the
support poles created a safety concern to operators and acted as a gas conduit
(Hartland Landfill Survey, Appendix C).
23
Table 10. Summary of responses from landfill bird control survey.
Landfill
Hartland
Nanaimo
Current Bird Control
Methods - Operational
x Reduced active face
x Cover with gravel
during operating
hours
x Cover with tarps at
the end of the day
Current Bird Control
Methods - Deterrents
x Trained birds of
prey on site from
October to May
x Screechers used
year round
Comments
x
x
x
Active face covered
with grind mixture at
the end of the day
x
x
CVWMC
x
x
x
CRWMC
x
x
7 Mile
x
Reduced active face
x
Planting of long grass
Covering of active
face with steel plates
at the end of the day
Reduced active face
x
Covering of active
face with steel plates
at the end of the day
Intermediate cover
x
using liner material
with reinforcements
Trained birds of
prey on site year
round
Two bird control
officers are on site
during the winter
months
Use skeets as a
secondary measure
year round
Starters pistol with
screamers and
bangers
x
x
x
Converted from
overhead wire
system to
trained birds of
prey
Have found
trained birds of
prey to be
effective
Bird control
measures have
reduced gull
numbers by
62% in 2011
Reduction was
maintained in
2012 and
lowered an
additional 4%
Have used an air
cannon and
bangers
Have used an air
cannon
24
4.0 Discussion and Conclusions
Landfills are anthropogenic, year round food sources that have altered the natural
feeding behaviour of some bird species. Identified bird species of concern at the Comox
Valley and Campbell River Waste Management Centres include gulls, Northwestern
Crows, Common Ravens and Bald Eagles.
Gulls are year round residents along the east coast of Vancouver Island and typically
nest in colonies on coastal islands. The breeding season of Glaucus-winged Gulls
extends from mid-April through mid-August (Verbeek 1993) coinciding with low reported
numbers present at the two regional landfills. Landfill operators have reported that gulls
are only present during daylight hours at the two regional waste management centres.
Crows and ravens typically build stick nests in trees but will also use cliffs as nesting
habitat. This type of habitat is present adjacent to the two regional landfills and corvids
may nest in the forested areas surrounding the landfills. There are no known Bald Eagle
nesting territories present at either of the two regional landfills. The landfills are
attractive to these bird species as a source of food, not due to the presence of breeding
habitat.
Observed species and numbers present at both landfills varied between the fall and
winter seasons with the highest numbers being observed during the winter months.
Gulls and corvids were present during both seasons but numbers increased dramatically
during the winter months. Peak gull numbers were recorded in January 2013 with 3,655
and 1,035 being observed at the CVWMC and CRWMC respectively. Corvid numbers
also peaked in January with highest counts of 138 at the CVWMC and 177 at the
CRWMC. The presence of Bald Eagles at the two sites is limited to the winter months
but they have a significant presence during this season (381 at CVWMC and 286 at
CRWMC). Historic spring counts completed at the CVWMC indicate that peak numbers
of gulls, corivds and eagles are limited to the winter and counts completed in May
typically include numbers of gulls between 121-252, 25 corvids and 22-40 ealges.
Seasonal variation in numbers and species can be attributed to availability of other food
sources, such as the timing of herring and salmon spawning, as well as breeding
activities. These seasonal variations in numbers and species influence the risks of
pathogen transport and required bird control measures.
25
Observations of bird behaviour at the active face of the two regional waste
management centres identified that only crows, ravens and eagles were observed
removing solid waste material from the active face. This activity was confirmed to be
more common during the winter months when corvid and eagle numbers increased but
the movement of solid waste material was limited to the perimeter of the two landfill
sites. The impact of landfill gulls on adjacent lands and waterbodies is limited to fecal
contamination as they were not observed to be transporting fomites offsite. Directional
observations confirmed a bird movement corridor between the landfill sites and adjacent
waterbodies at both the Comox Valley and Campbell River Waste Management Centres.
Observations at Comox Lake and McIvor Lake were not completed as part of this study
but bacterial source tracking confirmed the presence of E. coli from gulls within Comox
Lake and residents of McIvor Lake have confirmed the presence of gulls on the lake
during the winter. The movement of birds from the landfill in the direction of adjacent
lakes was observed during both the fall and winter seasons. The majority of
observations of birds using this movement corridor were gulls but corvids were also
observed, particularly at the CRWMC moving towards McIvor Lake. Bald Eagles present
at the landfills were not observed moving in the direction of the lakes at either site.
The mechanisms of potential pathogen transport vary by species. Gulls, Northestern
Crows, and Common Ravens act as vectors and have the potential to impact water
quality in Comox Lake and McIvor Lake through fecal contamination. Northwestern
Crows, Common Ravens and Bald Eagles pose a risk of fomite transfer to the perimeter
of the landfill sites. The movement of fomites to adjacent lands does not appear to pose
a risk of pathogen transport to humans as the transmission pathway (i.e. ingestion) is
unlikely. The greatest risk of pathogen transport due to landfill birds is to adjacent
waterbodies in the form of fecal contamination by gulls due to the high numbers of gulls
present during the winter months and the high frequency that they were observed
moving towards Comox Lake and McIvor Lake.
Due to their opportunistic and gregarious nature, gulls may be important reservoirs
and vectors for anthropogenically derived fecal pathogens in coastal areas. As a
consequence of feeding on anthropogenic waste a number of enteric bacteria such as E.
coli, Salmonella spp., and Campylobacter spp. have been isolated from intestinal
samples of gulls (Hatch, 1996: Moore et al., 2002) with the latter two being the most
common pathogens associated with gull feces (Ogden et al., 2009). Gulls can transfer
26
fecal bacteria to drinking water (Benton et al., 1983) and are also associated with
increased prevalence of fecal coliforms in recreational water (Levesque et al., 1993) and
at recreational beaches (Fogarty et al., 2003; Whitman and Nevers, 2003).
Although causal relationships for transmission of diseases from gulls to humans are
difficult to document, increasing evidence suggests that gulls may be important vectors.
Contamination of public water supplies by gull feces has been stated as the most
plausible source for disease transmission (Jones et al, 1978). However, evidence
suggests that gulls act as dispersal agents for pathogens (e.g. Salmonella) rather than
being primary sources (Hatch, 1996). The two enteric pathogenic bacteria identified to
be of the greatest concern due to gull fecal contamination to Comox Lake and McIvor
Lake are Campylobacter and Salmonella.
A report prepared for the CVRD as part of the Comox Lake watershed assessment
identified that animal wastes associate with the landfill could reduce Comox Lake water
quality due to nutrient loading (could lead to increased growth of unwanted algae) and
the introduction of pathogens (CH2MHILL, 2006b). A review of water quality in Comox
Lake was completed by the Ministry of Environment and results indicated that the
general water quality was good but that E. coli levels exceeded provincial guidelines
frequently, especially in the eastern portions of the lake (Epps and Phippen, 2011).
Gulls have been identified as a source of fecal contamination within Comox Lake
through specific bacterial source tracking but the greatest source of fecal contamination
identified in Comox Lake was human (UVic, 2012).
A review of water quality within McIvor Lake was completed by the Ministry of
Environment and results indicated that the general water quality was good. Highest E.
coli results in McIvor Lake were recorded in August/September when bird numbers
reported for the CRWMC are the lowest. The measured increase in E. coli could
possibly be caused by high recreational use of the lake during the summer season. No
bacterial source testing has been completed for McIvor Lake to separate bird impacts
from other possible sources.
Water quality monitoring in Comox Lake and McIvor Lake is focussed on fecal
coliform testing as indicators of fecal contamination. These indicators are not adequate
to detect the presence of Campylobacter and Salmonella. Organisms which are
27
pathogenic to humans and other warm-blooded animals are rarely capable of long term
survival as free-living organisms (Warrington, 1988). Human exposure to pathogens
identified as being potentially transferred to adjacent waterbodies could be from
immersion or accidental ingestion/inhalation during recreational activities or through
consumption of contaminated drinking water. Exposure to pathogens through ingestion
or inhalation may cause gastrointestinal diseases while direct contact with mucus
membranes and skin through immersion may cause eye, ear, nose, throat and skin
infections.
Recreational water monitoring for primary contact is completed during the summer
months by VIHA Environmental Health Officers. No beach closures have been required
at either Comox Lake of McIvor Lake. Current recreation water monitoring programs use
coliform counts as indicators of the presence of fecal contamination and related risks to
the public. As coliforms are not adequate indicators of the presence of Salmonella or
Campylobacter and there is no monitoring done for these bacteria there is a risk to public
health of exposure to these pathogens during primary contact recreation activities in
Comox Lake and McIvor Lake. Fecal contamination of lake water due to gulls is
expected to be higher in the winter due to the observed increase in gulls at the two
regional landfills during the winter season. Primary contact recreation activities are not
as likely during the winter months at Comox Lake and McIvor Lake but exposure is still
possible. Without specific testing of the presence of Salmonella or Campylobacter within
Comox Lake and McIvor Lake it is impossible to quantify the level or risk to the public of
exposure to these pathogens through primary contact recreation.
Wildlife contamination in the eastern portion of Comox Lake was identified as a high
risk source of contamination to the drinking water supply for the Comox Valley
(CH2MHILL, 2006a). Fecal contamination of water by animals is generally considered to
be less of a concern to human health than contamination by humans because there is
less risk of inter-species transfer of pathogens (Warrington, 2001). Gulls have been
shown to transmit human pathogenic strains of both Campylobacter and Salmonella,
resulting in a risk of transfer of pathogens to humans due to the presence of gulls at the
landfill. Waters contaminated with human feces are generally regarded as a greater risk
to human health than water contaminated with animal feces, as this water is more likely
to contain human-specific enteric pathogens (Scott et al., 2002). The identification of
human sourced bacteria within Comox Lake represents a risk to water quality and the
28
potential exposure of humans to pathogens. Currently, the CVRD treats drinking water
through chlorine disinfection prior to distribution. To effectively treat the water for viruses
and parasites the CVRD may be required to provide additional disinfection such as UV
or ozone and/or treatment such as filtration (Epps and Phippen, 2011). The City of
Campbell River disinfects drinking water with chlorination and ultraviolet light prior to
distribution (Brunn, pers.comm., 2010), to protect against pathogenic microorganisms.
Chlorination should be adequate to disinfect drinking water for Campylobacter and
Salmonella resulting in very low risk of transmission of these pathogens to humans
through contaminated drinking water.
Although potentially pathogenic fecal bacteria have been isolated from some species
of wild birds, recent reviews (Reed et al., 2003: Dixon 2007) suggest that the role wild
birds play in human diseases is largely understudied, and that much work remains to
determine the role of wild birds in zoonotic transmission of enteropathogens.
Based on the evaluated risks and winter bird numbers observed, additional bird
control measures are required at the two regional waste management centres. This
assessment has identified that the greatest risk to human health due to landfill birds is
fecal contamination of Comox Lake and McIvor Lake by gull feces. Bird control
measures should focus on reducing gull numbers at both the CVWMC and the CRWMC
during the winter months.
Two possible options to reduce gull numbers at landfills include enclosure of the
active area via wires or netting and the use of trained birds of prey. Both options are
costly and labour intensive.
Covering the active face requires a large initial investment, creates obstacles to
movement around the active face and requires maintenance. Separating food waste,
disposable diapers and pet feces (pathogen sources) from other types of garbage will
reduce the total area required to be covered. Waste disposal facilities consisting only of
non-putrescible waste do not attract gulls (Gabrey et al., 1994; Gabrey, 1997). If this
option is explored in the future perhaps an enclosed area could be used to compost food
waste until it is unattractive to birds and then landfilled.
The use of trained birds of prey to reduce bird numbers will require the services of a
bird control officer and is required daily during peak bird season. Gull numbers have
29
been reduced by employing trained birds of prey at both the Nanaimo Regional Landfill
and the Hartland Landfill but both sites still have between 300-1000 gulls on site during
the winter months. Employing trained birds of prey at the CVWMC and CRWMC will
reduce gull and corvid numbers but will not eliminate their presence or the risk of fecal
contamination to nearby waterbodies due to landfill birds. Differences between bird
species present at the two regional landfills operated by CSWM and the Nanaimo and
Victoria landfills must be considered when evaluating the potential use of trained birds of
prey for bird control. Between 187 to 381 Bald Eagles are present during the winter
months at the Comox Valley and Campbell River Waste Management Centres. Trained
birds of prey will not control eagle numbers and the presence of eagles can be a danger
to birds used by bird control officers. Bald Eagles can be very aggressive towards
falcons causing injury or even death to trained birds. Experienced birds and operators
will be required due to the presence of eagles and potential service providers will need to
assess the situation and develop a plan given the numbers and species present at the
two sites. Trained birds will not reduce the number of eagles present on site and the
movement of plastic to the perimeter of the sites.
Hartland Landfill has utilized both cover and trained birds of prey and have chosen to
use the latter as their current method of bird control.
No bird control measure or technique will work consistently over time unless they are
applied and adapted properly by appropriately trained personnel. Programs should have
a biological basis and efforts should be quantified by counting birds on site to evaluate
effectiveness. The CVWMC site is isolated thereby reducing potential impacts and
conflicts with adjacent lands and neighbours. At the CRWMC a coordinated effort with
neighbouring Island Ready Mix will be required as gulls commonly roost on the buildings
and lands within their property.
Management of bird populations at landfill sites is an ongoing issue and due to public
concerns relating to this issue and nearby waterbodies at both the Comox Valley and
Campbell River sites it is suggested that additional bird control measures be employed
during the winter months at both the regional waste management centres. The Comox
Strathcona Waste Management 2012 Solid Waste Management Plan which is intended
to guide how the region manages its garbage includes only minimal discussion on bird
30
control measures. It includes a brief section on Wildlife Conflict Management focussed
on bears with only one bullet relating to birds:
“Maintain and improve bird management at the landfill working face at the Comox
Valley waste management center and the Campbell River waste management
center. As part of this initiative, a study will be undertaken in 2012 that includes
quantitative and qualitative analysis of birds that contact waste at the landfill and
their impacts on adjacent lands and waters.” (AECOM, 2012)
A formal plan for bird control needs to be established and incorporated into updates
to the CSWM Solid Waste Management Plan. Based on this study and feedback from
other Vancouver Island landfill operators trained birds of prey appears to be the best
option for reducing gull numbers at the two regional landfills. This study has identified
that the greatest risk of pathogen transport to humans due to landfill gulls is fecal
contamination of Comox Lake and McIvor Lake during the winter months. As water
quality testing results within Comox Lake have been shown to exceed drinking water
guidelines the greatest need for bird control measures is at the CVWMC. It is suggested
that services of trained birds of prey could be initiated as a trial at the CVWMC and then
expanded to CRWMC if shown to be effective, cost efficient and dependent on plans for
operational changes for the Campbell River site to function as a transfer station, which
may influence the requirement of bird control.
Results of this bird impact assessment study at the Comox Valley and Campbell
River Waste Management Centres indicate that the presence of birds at the two landfills
and their impacts on adjacent lands and waterbodies is a complex issue of public
concern requiring a multidisciplinary approach. This study includes interpretations of
water quality data as well as measures of risk to public health. The identified public
health risks due to landfill bird populations should be reviewed with representatives from
water quality and drinking water services as well as the Vancouver Island Health
Authority to ensure accurate assumptions have been made and to further evaluate public
health risks. Issues identified through this study are summarized in Table 11.
31
Adjacent
waterbodies
Adjacent
waterbodies
Adjacent
lands
Movement of
fomites
Fecal
contamination
Fecal
contamination
Fecal
contamination
Northwestern
Crow,
Common Raven
Gulls,
Northwestern
Crow,
Common Raven
Gulls,
Northwestern
Crow,
Common Raven
Gulls,
Bald Eagles,
Northwestern
Crow, Common
Raven
Perimeter of
landfills
Movement of
fomites
Bald Eagles
Area of
Impact
Perimeter of
landfills
Issue
Species
Salmonella,
Campylobacter
Salmonella,
Campylobacter
Salmonella,
Campylobacter
Bacterial pathogens,
human enteroviruses,
human noroviruses
and protozoan
parasites potentially
present in landfill
material.
Potential Pathogen
Transport
Bacterial pathogens,
human enteroviruses,
human noroviruses
and protozoan
parasites potentially
present in landfill
material.
Accidental ingestion
and immersion
through primary
contact recreation.
Transmission to
public via ingestion is
unlikely.
Transmission to
unlikely.
Ingestion through
contaminated
drinking water.
Transmission to
unlikely.
Employees of the
landfills may be
exposed through
direct contact.
Transmission
Pathway
Employees of the
landfills may be
exposed through
direct contact.
Low Risk
Risk is present
Low Risk
Low Risk
Low Risk
Risk
32
Numbers will be
reduced by trained
birds of prey and
cover.
Numbers will be
reduced by trained
birds of prey and
cover.
Numbers of crows,
ravens and gulls will
be reduced by
trained birds of prey
but eagles will not be
affected. Covering
will reduce numbers
of all species.
Numbers will be
reduced by trained
birds of prey and
cover.
Cover will reduce
numbers.
Numbers will not be
reduced by trained
birds of prey.
Effect of Bird Control
Table 11. Summary of issues relating to bird species present at the Comox Valley and Campbell River Waste Management Centres.
CONCLUSIONS:
x
Bird species composition and numbers present at the Comox Valley Waste
Management Centre and the Campbell River Waste Management Centre vary
between fall and winter.
x
Landfills are used as a food source, no nesting occurs within the two regional
landfills.
x
Mechanisms of pathogen transport vary by species. Gulls, Northwestern
Crows and Common Ravens pose a risk of fecal contamination to adjacent
waterbodies. Northwestern Crows, Common Ravens and Bald Eagles pose a
risk of fomite transfer to the perimeter of the landfill sites but distance appears
to be limited.
x
Fomite movement to adjacent lands by Northwestern Crows, Common
Ravens and Bald Eagles pose a low risk of pathogen transport to humans as
the transmission pathway (i.e. ingestion) is unlikely.
x
Movement of landfill gulls in the direction of adjacent lakes has been observed
at both sites through directional observations completed as part of this study.
Bacterial source tracking have confirmed the presence of gulls at Comox
Lake. Observations by residents of McIvor Lake indicate that gulls are
common at the lake during the winter months.
x
Pathogens identified that could be transported or caused by gull fecal
contamination of Comox Lake and McIvor Lake include Camplylobacter spp.
and Salmonella spp. Water quality monitoring or testing is not completed for
either of these enteric pathogens.
x
Potential exposure to Campylobacter and Salmonella could occur through
primary contact recreation within McIvor Lake and Comox Lake. Recreational
water quality monitoring of coliform levels may not indicate the presence of
these bacteria within lake water.
x
Water quality is generally good within Comox Lake and McIvor Lake although
E. coli testing results in Comox Lake from between 2005-2007 frequently
exceeded MOE drinking water guidelines.
33
x
Existing drinking water treatment in Campbell River includes chlorination and
ultraviolet light which would adequately treat water for Campylobacter and
Salmonella.
x
Existing drinking water treatment in the Comox Valley includes chlorination but
no secondary treatment for viruses or parasites. Chlorination should be
adequate to disinfect water and eliminate exposure to Campylobacter and
Salmonella.
x
Additional winter bird control measures are required at the Comox Valley
Waste Management Centre and the Campbell River Waste Management
Centre.
x
The highest priority for winter bird control determined by risk of pathogen
transport to humans is the Comox Valley Waste Management Centre.
34
5.0 Recommendations
To further the knowledge gained through this bird impact assessment study and to
better understand the risks landfill birds pose to nearby lands and waterbodies the
following actions are recommended:
x
Additional observations at the CVWMC and CRWMC during the spring and
summer seasons to document changes in species composition and number
over the entire year. These observations will also document seasonal
changes in behaviour including movement patterns and feeding.
x
Observations at Comox Lake and McIvor Lake to confirm the presence of
landfill bird species at these sites and survey for solid waste material. These
surveys should be completed during all seasons.
x
Test fomites for pathogens to determine if the movement of landfill material
represents a risk to human health.
x
Testing for Campylobacter and Salmonella spp., the two pathogenic
microorganisms identified as potential concerns, should be completed in
Comox Lake and McIvor Lake. Sampling should be completed during the
winter and possibly during other seasons depending on results of
observations during the spring and summer.
x
Establish a bird control program for the CVWMC and the CRWMC. Suggest a
trial of trained birds of prey at the CVWMC as gulls present at this site pose
the greatest risk to human health through fecal contamination of Comox Lake.
o
Services would be required during the winter months, beginning in
October. As study observations have not been completed in the spring
an end date will need to be determined by discussion with landfill
operators. Historic bird count data indicates services will not be
required in May.
o
Effect on bird numbers and species should be quantified in order to
evaluate the success of the program.
o
Program could be expanded to CRWMC if deemed effective in
reducing gull numbers.
35
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Benjamin, L. and G. Vasarhelyi. 2006. Comox Lake Watershed Assessment:
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Broman, T., Palmgren, H., Bergstrom, S., Sellin, M., Waldenstrom, J., Danielsson-Tham,
M.L., and Olsen, B. 2002. Campylobacter jejuni in Black-headed Gulls (Laurus
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Brunn, J. 2010. Personal communication. Water Supervisor. City of Campbell River,
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Carter, A.M., Pacha, R.E., Clark, G.W., and Williams, E.A. 1987. Seasonal occurrence
of Campylobacter spp. in surface waters and their correlation with standard
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CH2MHILL. 2006a. Comox Lake Watershed Assessment Characterize Risks –
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Clark, C.G., Price, L., Ahmed, R., Woodward, D.L., Melito, P.L., Rodgers, F.G.,
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Clayton, W.E.L. 2005. Microbial Source Tracking Study in Support of Comox Lake
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Cordner, K. 2013. Personal communication. Environmental Health Officer. Vancouver
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Dayton and Knight Ltd. 2001. District of Campbell River Watershed Management Plan.
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Dixon, B. 2007. Disseminators aloft? Microbe 2:416-417.
Epps, D. and B. Phippen. 2011. Water quality assessment and objectives for Comox
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Ferron, J. 2013. Personal communication. McIvor Lake resident and representative on
the Campbell River Watershed Committee.
Field, K.G. and M. Samadpour. 2007. Fecal source tracking, the indicator paradigm, and
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22:288-295.
Gerba, C.P., Tamimi, A.H., Pettigrew, C., Weisbrod, A.V., and Rajogopalan, V. 2011.
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Haack, S.K., J.W. Duris, L.R. Fogarty, D.W. Kolpin, M.J.Focazio, E.T. Furlong, and M.T.
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Health Canada. 2004. Guidelines for Canadian drinking water quality: Supporting
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Isfeld, J. 2011. Comox Valley Regional District Staff Report – Bird Control and Impact at
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39
Appendix A
Landfill Bird Control Survey
Completed by:
Landfill:
Date:
Job Title:
Operational procedures used to reduce bird numbers at landfill
Please describe any procedures such as covering, reducing active face, planting, etc., that
have been utilized on site and the effects that these activities had on bird numbers.
Procedure
Effect
Please describe any additional operational procedures that you would like to try in order to
reduce bird numbers.
Bird Deterrent Devices
Please comment on any devices that have been used at the landfill (past or present) and
their effectiveness in reducing bird numbers.
Device
Have If yes, please comment on their effectiveness in
Used reducing bird numbers highlighting the most effective
Cannon
Y N
Alarm/Distress Calls
Y N
Whistle Bombs,
Y N
Bangers, Noise Rockets
Agricultural Explosive
Y N
Devices
Scare Balloons
Y N
Predator Silhouettes
Y N
and/or Models
Streamers or Whirlers
Y N
RC Aircraft
Y N
Trained Birds of Prey
Y N
Physical Barriers Y N
enclosure
Physical Barriers - tarps
Y N
Overhead Netting
Y N
System
Shooting
Y N
Toxicants
Y N
Other – please specify
I
Current Bird Control Measures
Please describe any bird deterrent devices and/or combination of devices that are currently
being used. Include details of frequency of use and/or seasons of use.
Please describe or list any additional bird deterrent devices that you would like to try.
Please describe an optimal landfill bird control program that you would recommend
based on your experience.
Other Comments:
We appreciate your time and valuable feedback.
Thank you!
II
Appendix B
Photo 1
Looking west along the slope on the southeast boundary of the landfill area of the
CVWMC on September 12, 2012 showing gulls present during the fall season.
Photo 2
Looking west along the slope on the southeast boundary of the landfill area of the
CVWMC on January 22, 2013 showing gulls present during the winter season.
III
Photo 3
Gulls present at the top of the landfill section of the CRWMC on September 9, 2012
during the fall season.
Photo 4
Gulls present at the top of the landfill section of the CRWMC on January 23, 2013
during the winter season.
IV
Photo 5
A photo showing some of the Bald Eagles present at the CVWMC during the winter
season, January 22, 2013.
Photo 6
A photo showing some of the Bald Eagles present at the CRWMC during the winter
season, January 9, 2013. Notice the yellow plastic bag transported from the active
face into the tree by eagles.
V
Appendix C
Selected University of Victoria data collected from the Comox Lake watersource.
Records presented include all samples where gulls were listed as at least one of the
bacterial sources of E. coli between Sept. 5, 2010 and November 5, 2012 (UVic, 2012).
Sampling Station
Sample Date
COM-02 (26m HYPO)
COM-02 (surface EPI)
COM-01 (Intake)
COM-02 (9m META)
COM-02 (29m HYPO)
COM-02 (9m META)
COM-02 (29m HYPO)
COM-01 (Intake)
COM-02 (29m HYPO)
COM-02 (9m META)
COM-01 (Intake)
COM-02 (9m META)
COM-02 (29m HYPO)
COM-01 (Intake)
COM-02 (29m HYPO)
COM-01 (Intake)
COM-01 (Intake)
COM-02 (9m META)
COM-02 (29m HYPO)
COM-02 (9m META)
COM-02 (29m HYPO)
COM-01 (Intake)
COM-01 (Intake)
COM-01 (Intake)
COM-01 (Intake)
COM-01 (Intake)
COM-01 (Intake)
COM-01 (Intake)
COM-01 (Intake)
COM-02 (30m HYPO)
COM-02 (20m META)
COM-01 (Intake)
COM-01 (Intake)
COM-02 (20m META)
COM-01 (Intake)
COM-02 (20m META)
COM-01 (Intake)
COM-01 (Intake)
8-Sep-10
14-Sep-10
28-Sep-10
28-Sep-10
28-Sep-10
28-Sep-10
5-Oct-10
5-Oct-10
5-Oct-10
13-Oct-10
13-Oct-10
19-Oct-10
19-Oct-10
27-Oct-10
27-Oct-10
27-Oct-10
27-Oct-10
2-Nov-10
10-Nov-10
16-Nov-10
16-Nov-10
23-Nov-10
23-Nov-10
30-Nov-10
30-Nov-10
6-Dec-10
14-Dec-10
14-Dec-10
21-Dec-10
25-Jan-11
31-Jan-11
8-Feb-11
15-Feb-11
22-Mar-11
12-Apr-11
10-May-11
14-Jun-11
28-Jun-11
25-Jul-11
25-Jul-11
3-Aug-11
10-Aug-11
6-Sep-11
19-Sep-11
31-Oct-11
21-Feb-12
5-Mar-12
24-Apr-12
11-Sep-12
E. coli
(CFU/100ml)
3
0.5
4
4
8
17.5
1.5
2.5
8
2.5
5
2
0.5
3.5
3.5
4
7.5
3.5
1
3.5
0.5
6.5
1
2.5
1
0.5
1.5
1
2.5
5.5
2
3.5
2.5
13.5
1
1
4.5
2.0
0.3
0.3
0.3
0.3
0.7
2.3
7.3
1.7
0.3
1.0
1.0
Bacterial Sources Identified
Gull, Marmot, Horse, Gull, Black Bear
Gull
Marmot, Gull
Dog, Gull
Raccoon, Raccoon, Gull, Gull,
Gull, Human
Human, Gull
Gull, Gull
Gull, Gull
Gull
Gull, Gull
Gull, Gull
Gull
Gull, Human, Black bear
Human, Gull, Human
Gull, Human, Gull
Human, Gull, Gull
Gull, Gull
Gull
Gull
Gull
Gull
Gull
Dog, Gull
Gull
Gull
Gull
Gull
Gull, Gull,
Raccoon, Gull, Gull, Gull,
Gull
Human, Gull, Gull, Human
Gull
Cow, Gull, Horse, Wolf
Gull, Human
Horse, Gull
Coyote, Mule deer, Elk, Elk, Gull
Gull, Marmot
Gull
Gull
Gull
Gull
Gull
Gull, Black Bear, NI
Coyote Raccoon Human Black bear Gull
Gull, Human, Black bear
Gull
Raccoon, Gull
Gull, Human, Human
VI
Appendix D
Completed by: Drew Fafard
Landfill: Hartland, CRD
Date: Jan. 30, 2013
Job Title: Manager Hartland Landfill
Procedure
Effect
Active face restricted to 30m
These operational procedures have helped but there
would still be thousands of gulls present in the winter
without a bird control officer.
No exposure – covered at end of
day with tarps
Gravel as cover during operations
Device
Cannon
Y
Used in past – birds became habituated
Y
Used in past – birds became habituated
Whistle Bombs,
Y
N
Devices
Scare Balloons
Y
Tried kites
N
and/or Models
N
RC Aircraft
N
Have been approached by someone wanting to try this.
Y
Currently have a bird control officer on site from Oct. to
May
Physical Barriers N
enclosure
Y
Tarps over active face at end of day
Overhead Netting
Y
Very effective initially, upkeep very expensive, quickly
System
deteriorated, poles were a safety hazard to workers, birds
were occasionally caught in the wires, poles used to
support wires were a gas conduit. Birds were still in the
area but they were unable to access active face.
Shooting
N
Toxicants
N
VII
Currently have a bird control officer on site during peak bird months – mid October to May 1.
Use PNW Raptors for bird control (Robin). Screechers are currently being used in
conjunction with a bird control officer (Oct – May) and are the sole bird control measure from
May – October.
With these measures in place birds are still in the area but they do not land on the active
face. No garbage is transported off site – reduced complaints from neighbours.
Current bird control measures are adequate.
Current combination of operational procedures and bird control officer are adequate.
Other Comments:
Bird control officer probably costs more than the overhead wire system but there were some
gaps in the tracking of costs associated with maintenance of the overhead wire system so it’s
difficult to say for sure.
Thank you!
VIII
Completed by: Jon Isfeld
Landfill: CVWMC
Date: February 2, 2013
Job Title: Assistant Manager of Comox Valley Waste
Services
Procedure
Effect
Smaller active face
Less waste available to vectors
Planting long grass
Less resting area for vectors
Device
Cannon
Y
Not effective at all after short period – birds roosting on it
Y
Effective for short term
Whistle Bombs,
Y
Very effective for short periods but does need to be
repeated constantly – effect diminishes after continued
use
N
Devices
Scare Balloons
N
N
and/or Models
N
RC Aircraft
N
N
Physical Barriers N
enclosure
Y
Use of steel plates to cover waste at end of day is highly
effective
Overhead Netting
N
System
Shooting
N
Toxicants
N
IX
Starters pistol with screamers and bangers is effective for short periods but needs to be
repeated often to have measurable effect in moving birds off the site rather than just around
the site.
Other Comments:
Thank you!
X
Completed by: Patrick Donaghy
Landfill: 7 Mile Landfill
Date: Jan 30, 2013
Job Title: Operation Manager
Procedure
Effect
Intermediate Cover using liner
material with reinforcements
Scattering Xmas tinsel as a
distraction.
Used air cannon
Appears to keep birds from landfill face when applied.
Gulls, eagles and crows still linger for opportunities
when is not covered
Negligible
Limited impact
Device
Cannon
Y
N
Whistle Bombs,
N
N
Devices
Scare Balloons
N
N
and/or Models
N
RC Aircraft
N
N
Physical Barriers N
enclosure
Y
Overhead Netting
N
System
Shooting
N
Toxicants
N
XI
We keep the landfill face covered at night and try and keep the exposure to a minimum
during operating hours.
The only effective control mechanism is to keep the active landfill face covered and as
inaccessible as possible to birds and wildlife. Toxins and shooting will never be
allowed especially if bald eagles are in the equation. Likewise a hawk is of little impact
versus a bald eagle or crows for that matter.
Other Comments:
Thank you!
XII
Completed by: PK Bird Control Services (Kevin Letts)
Landfill: RDN 1105 Cedar Rd
Date: Feb 14, 2012
Job Title: Bird Control Officer/Owner
Procedure
Effect
RDN Operators dump a grind
This helps cover food/debris that the birds would
mixture on active face/cell before
otherwise eat/carry off
leaving for the day
Device
Used reducing bird numbers highlighting the most
effective***
Cannon
Y N
Y N
Whistle Bombs,
Y N
Y N
Devices
Scare Balloons
Y N This works for a short period of time (a couple of days) the
balloons must be moved around, it does not work for all
birds
Y N This keeps swallows out of the workshops, but unless
and/or Models
they are moved around on a constant basis the birds will
realize they are as good as a perch
Y N This is also a short term fix, and wind is needed.
RC Aircraft
Y N
Y N *** We find this is the best method of deterring most pests
and due to the fact that they chase and catch the pest
birds man-made products can not compete.
Physical Barriers –
Y N
enclosure
Y N
Overhead Netting
Y N
System
Shooting
Y N
Toxicants
Y N
XIII
We fly our birds in all season, we do have secondary measure (ie: skeets clay disks) that we
also utilize in conjunction. During the winter months when the numbers grow we often set up
Scare crows in different location and we also have two BCO’s on site. After the Herring Run
Go down to one BCO and it is manageable.
Net gun, we feel if used, it would cause enough panic with the caught bird that it would leave
And others would be off as well due to the distress in that moment.
We feel our program has been very successful. From 2010 to 2011 PK Bird Control
reduced gull numbers at the landfill by 62% and in 2011 to 2012 maintained the
reduction and even managed to lower it an addition 4% over all.
Other Comments:
Most of the items on your list we have tried but either due to ineffectiveness or site
regulations we opted to stop (ie: bangers – due to dangers near methane well heads)
Thank you!
XIV
Completed by: Matt Pederson
Landfill: Campbell River
Date: March 5, 2013
Job Title: Berry & Vale Operator
Procedure
Effect
Metal plates
Limits but doesn’t deter birds
Small lifts
Limits but doesn’t deter birds
Birds will dig for garbage.
Device
Cannon
Y
Works if intervals are changes
N
Whistle Bombs,
Y
Works, more effective than cannon
N
Devices
Scare Balloons
N
N
and/or Models
N
RC Aircraft
N
N
Physical Barriers N
enclosure
Y
Birds will dig under tarps
Overhead Netting
N
System
Shooting
N
Toxicants
N
XV
Air cannon is used daily, same with daily cover with metal plates until active face is to proper
grade then covered with gravel.
They are persistent so something needs to be on them all day at active face to keep
them from getting at garbage. More frequently than air cannon fire or a rapid use of
noise gun.
Other Comments:
Thank you!
XVI

Bird Impact Study - Comox Strathcona Waste Management Service

Transcription

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