COLUMBIA SHUSWAP REGIONAL DISTRICT

REVELSTOKE & ELECTORAL AREA ‘B’

NUISANCE MOSQUITO CONTROL PROGRAM

2018 YEAR-END REPORT

Prepared by: Burke Phippen, BSc., RPBio. Project Manager

Cheryl Phippen, BSc., RN Field Coordinator

NOVEMBER 2018 BWP CONSULTING INC., 6211 MEADOWLAND CRES S, KAMLOOPS, BC V2C 6X3 2018 Revelstoke & Electoral Area ‘B’ Mosquito Control Program

Table of Contents

LIST OF FIGURES ...... II

LIST OF TABLES ...... II EXECUTIVE SUMMARY ...... 1

1.0 INTRODUCTION ...... 2 2.0 ENVIRONMENTAL FACTORS ...... 3

2.1. SNOW PACK ...... 4 2.2. TEMPERATURE AND PRECIPITATION ...... 4

2.3. FLOW LEVELS ...... 7 3.0 LARVICIDING PROGRAM ...... 11

3.1. HAND APPLICATION OF BTI LARVICIDE ...... 13 3.2. HELICOPTER APPLICATION OF LARVICIDE ...... 14

4.0 PUBLIC OUTREACH...... 15 5.0 LIGHT TRAPS ...... 15

5.1. ANALYSIS OF 2018 LIGHT TRAP CATCH ...... 16 6.0 BIOLOGY OF MOSQUITO SPECIES COLLECTED ...... 16

6.1. AEDINES AND OCHLEROTATUS SPECIES ...... 16 6.1.1. Aedes vexans ...... 17 7.0 CONCLUSIONS ...... 17

REFERENCES ...... 17

APPENDIX I. SUMMARY OF LARVICIDING ACTIVITIES CONDUCTED WITHIN THE CITY OF

REVELSTOKE & ELECTORAL AREA ‘B’ IN 2018 WITH AQUABAC 200G ...... 18 APPENDIX II. MOSQUITO CONTROL BROCHURE ...... 20

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LIST OF FIGURES Figure 1. Overview map of Revelstoke & Electoral Area ‘B’ mosquito control area. The sites have been labelled with site codes which correspond to monitoring and treatment data...... 3 Figure 2. Snow pack at Mt Revelstoke in 2018, compared with historical records...... 5 Figure 3. Minimum and maximum daily temperatures (°C) measured at Revelstoke Airport (Environment Canada Climate ID 1176755)...... 6 Figure 4. Daily precipitation (mm) measured at measured at Revelstoke Airport (Environment Canada Climate ID 1176755)...... 6 Figure 5. Average daily discharge from Illecillewaet River at Greeley for 2018 (measured at Environment Canada hydrometric station 08ND013), compared with recent years and peak years...... 8 Figure 6. Average daily water levels in Upper Arrow Lake in 2018 (measured by BC Hydro at , 08NE104), compared with recent years and peak years...... 10

LIST OF TABLES

Table 1. Summary of maximum instantaneous discharge for Illecillewaet River at Greely (Environment Canada Hydrometric station 08ND013) between 1998 and 2017...... 9 Table 2. Summary of maximum water level for Upper Arrow Lake at Nakusp (Environment Canada Hydrometric Station 08NE104) between 1998 and 2018. .... 11 Table 3. Summary of granular larvicide (Bti) applications in Revelstoke & Electoral Area ‘B’ in recent years...... 13 Table 4. Summary of total hand applications of larvicide within each site in the City of Revelstoke & Electoral Area ‘B’ in 2018...... 13 Table 5. Summary of helicopter larviciding activities conducted in Revelstoke in 2018 by date...... 14 Table 6. Summary of total helicopter larviciding applications in each site in Revelstoke & Electoral Area ‘B’ in 2018...... 14

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EXECUTIVE SUMMARY

Snowpack on Mount Revelstoke was slightly above average in 2018. Average air temperature was below average in April but above average in May through July. Precipitation was above average in April and June, and below average in May and July. Maximum water level on the Illecillewaet River occurred much earlier than normal (on May 16th) and was lower than the average for the last 20 years. The reached its highest peak on July 13th at 439.733 m which is 1.3 m higher than the 20-year average.

This year a total of 3,471.5 kg of larvicide (Aquabac 200G) was applied to 694.5 ha of larval development area. Of this, a total of 104.5 kg of larvicide was applied by hand or backpack blower to 20.9 ha of larval development habitat, and 3,367.0 kg of larvicide was applied to 673.6 ha of habitat by helicopter. Helicopter larviciding was conducted on four dates (June 8th, June 20th, June 29th, and July 23rd.

One light trap was deployed on Pratico Road near the Airport. Over the course of the summer, only a few specimens of Aedes vexans (a floodwater mosquito that is a ferocious biter) were captured.

The Revelstoke Farmers’ Markets was attended by BWP Consulting staff on July 28, 2018, to answer questions and to educate landowners about mosquitoes and the mosquito control program.

2018 marks the seventh year that BWP Consulting Inc. has conducted the nuisance mosquito control program in Revelstoke & Electoral Area ‘B’.

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1.0 INTRODUCTION

The Columbia Shuswap Regional District has conducted a mosquito control program in the City of Revelstoke & Electoral Area ‘B’ since 2003. In 2012, a three-year contract was tendered to BWP Consulting Inc. (BWP) to conduct the mosquito control program in Revelstoke & Electoral Area ‘B’ and in 2015, this contract was extended for an additional two-years. The current contract is based on an annual larval treatment of up to 325 ha of habitat aerially (in up to three helicopter applications) and up to 10 ha of ground treatments. In addition, a contingency fund may be accessed should conditions require it. This report summarizes the work completed in 2018 by BWP staff, and makes recommendations for future improvements to the program. The habitat controlled within the Revelstoke & Electoral Area ‘B’ mosquito control program is primarily along the Columbia River south of the Revelstoke to just south of the Revelstoke airport and along the Illecillewaet River near its confluence with the Columbia River (Figure 1). Exceptions to this include the sites labelled as RV5, RV2 and RV 7 in Figure 1 which are ponds situated a significant distance from the two major rivers. The mosquito control program utilized in Revelstoke & Electoral Area ‘B’ is based on larviciding, whereby mosquito larvae are targeted with the use of biological controls prior to emergence as adults. The size and distribution of larval development sites within a control area (and therefore the number of larvae produced and the amount of larviciding necessary to control these populations) can fluctuate considerably from year to year, primarily as a factor of environmental conditions. Environmental conditions within the City of Revelstoke & Electoral Area ‘B’ in 2017 are discussed in Section 2.0. Larviciding activities (including ground and aerial applications of larvicides) are discussed in Section 3.0. Technicians rely upon feedback from the general public to aid in locating potential development sites, as well as to assess overall efficacy of the program from year to year. For this reason, we encourage the public to call and report potential larval development sites, as well as problems with adult mosquitoes. Service requests are summarized in Section 5.0. Finally, we rely upon adult mosquito trapping to determine species composition as well as to evaluate the efficacy of the larval control program, and this component of the program is discussed in Section 6.0.

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Figure 1. Overview map of Revelstoke & Electoral Area ‘B’ mosquito control area. The sites have been labelled with site codes which correspond to monitoring and treatment data.

2.0 ENVIRONMENTAL FACTORS Mosquitoes pass through seven stages during their life cycle: egg, four larval instars, pupa, and adult. Their eggs are laid in water or on moist soil, and the larvae require stagnant,

BWP Consulting Inc. Page 3 2018 Revelstoke & Electoral Area ‘B’ Mosquito Control Program relatively shallow standing water to mature and pupate. As adult mosquitoes are generally hardy and able to survive in a wide range of environments, mosquito populations are generally restricted only based on suitable larval habitat. Within the City of Revelstoke & Electoral Area ‘B’, the majority of larval habitat is produced from floodwater from the Columbia River (which fluctuates with Arrow Lake maintained by Keenleyside Dam) and Illecillewaet Rivers. There are also a few snowmelt sites. Snow pack, coupled with temperature and precipitation, are the predominant factors affecting snow-melt pools and water levels of the Illecillewaet River. The dam systems control the water levels of the Columbia River at Revelstoke (See Section 2.3. ) Our staff receive weekly updates and water level predictions published by BC Hydro. These updates are used by our staff when planning aerial larviciding campaigns.

2.1. SNOW PACK Snow pack describes the volume of snow in a given area based on its water equivalent, or weight, rather than depth. This provides an objective means of measuring the absolute volume of snow that has accumulated at a site, since measuring depth alone does not take into consideration variations in snow density. Water equivalents are generally measured using snow pillows which are large plastic bags containing antifreeze. A pressure sensor records the weight of snow on top of the snow pillow, and converts this value to a volume in millimeters of water. The BC Ministry of Environment operates a number of these snow pillows throughout the province to determine the snow-pack in key watersheds. In most mosquito control programs in BC, the majority of larval habitat is produced by flooding rivers, and therefore snow pillows are useful for predicting potential flood levels relative to other years. The snow pillow nearest Revelstoke is located on Mt. Revelstoke (snow pillow #2A06P). Snowmelt from this area drains into Revelstoke Lake and the Columbia River upstream from Upper Arrow Lake. In 2018, snowpack levels were slightly higher than in recent years, peaking in late April and decreasing to zero by early July (Figure 2).

2.2. TEMPERATURE AND PRECIPITATION While the overall volume of snow (described by snow pack) dictates, to a large extent, the total discharge carried through the watershed, the timing of the melt (and therefore the timing and magnitude of peaks in river flow and lake levels) are strongly influenced by air temperature and precipitation. Warmer than average temperatures or large amounts of precipitation can result

BWP Consulting Inc. Page 4 2018 Revelstoke & Electoral Area ‘B’ Mosquito Control Program in rapid snow melt, and rapid rises in river levels. As well, rain falling on snow is not absorbed into the ground, but typically runs over the surface of the snow and is discharged into tributaries, and speeds snow melt. These factors can result in extremely rapid rises in water level and significant flooding. Daily maximum temperatures measured at the Revelstoke Airport (Environment Canada weather station #1176755, elevation 445 m) were cooler than usual in April, but above average in May through July (Figure 3). Precipitation was above average in April and June, but below average for both May and July (Figure 4).

Figure 2. Snow pack at Mt Revelstoke in 2018, compared with historical records.

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Figure 3. Minimum and maximum daily temperatures (°C) measured at Revelstoke Airport (Environment Canada Climate ID 1176755).

Figure 4. Daily precipitation (mm) measured at measured at Revelstoke Airport (Environment Canada Climate ID 1176755).

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2.3. FLOW LEVELS The majority of larval development area produced in and around the City of Revelstoke & Electoral Area ‘B’ is a result of rising water in the Columbia River downstream from Revelstoke Lake, the level of Upper Arrow Lake (which influences the Columbia River levels), and floodwaters from the Illecillewaet River. Control structures on Revelstoke Lake ( at the head of the Lake and at the outlet of the lake) regulate water releases into the Columbia River upstream from the City of Revelstoke. In addition, the Arrow Lake water levels, governed by the Hugh Keenleyside Dam near Castlegar, impact the discharge of water from the Columbia at Revelstoke. Flows in the Illecillewaet River are not controlled, and water levels peak during the late spring and are influenced by snowmelt and precipitation (Figure 5). Water levels in the Illecillewaet River rose rapidly in early May (likely as a result of precipitation events and higher than average air temperatures (see Figure 4)), and reached the annual peak of 290 m3/s in on May 16, 2018 (Figure 5). Typically, peaks on the rising arm of the hydrograph are a concern for mosquito control, because they wet new soil (and therefore the mosquito eggs that have been laid in that soil), resulting in a hatch and necessitating treatment. Peak water levels on the Illecillewaet were slightly below the average for the past 21 years, and occurred well before the average peak date of July 2 (Figure 5, Table 1). Water levels in Arrow Lake increased gradually through the spring until peaking on July 13, 2018 at 439.733 meters, slightly higher than the 2017 peak (Figure 6), and 1.3 m higher than the average peak based on the last 20 years (Table 2).

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Figure 5. Average daily discharge from Illecillewaet River at Greeley for 2018 (measured at Environment Canada hydrometric station 08ND013), compared with recent years and peak years.

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Table 1. Summary of maximum instantaneous discharge for Illecillewaet River at Greely (Environment Canada Hydrometric station 08ND013) between 1998 and 2017. Maximum Date when Instantaneous maximum Year Discharge (m3/s) occurred 1998 244 May 27 1999 383 Jul 19 2000 251 Jul 23 2001 258 Jun 02 2002 332 Jun 29 2003 305 Oct 21 2004 261 Jun 24 2005 238 Jun 06 2006 317 May 21 2007 353 Jun 04 2008 335 Jul 01 2009 210 Jun 05 2010 253 Sep 28 2011 394 Jul 08 2012 362 Jul 22 2013 318 Jul 02 2014 261 Jul 19 2015 268 Jun 08 2016 320 Jun 09 2017 405 Jun 09 2018 290 May 16

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Figure 6. Average daily water levels in Upper Arrow Lake in 2018 (measured by BC Hydro at Nakusp, 08NE104), compared with recent years and peak years.

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Table 2. Summary of maximum water level for Upper Arrow Lake at Nakusp (Environment Canada Hydrometric Station 08NE104) between 1998 and 2018. Maximum Date when Water Level maximum (m) occurred 1998 438.544 Jul 31 1999 440.034 Jul 29 2000 440.005 Jul 25 2001 432.18 Jan 01 2002 439.885 Jul 18 2003 439.047 Jul 04 2004 436.203 Aug 13 2005 434.619 Jul 02 2006 439.781 Jul 10 2007 438.581 Jul 07 2008 439.976 Jul 05 2009 437.561 Jun 30 2010 439.314 Jul 05 2011 439.515 Jul 28 2012 440.529 Jul 23 2013 439.919 Jul 04 2014 439.054 Jul 05 2015 435.439 Jun 13 2016 437.199 Jun 11 2017 439.535 Jul 28 2018 439.733 Jul 13

3.0 LARVICIDING PROGRAM

The City of Revelstoke & Electoral Area ‘B’ mosquito control campaign is focused on controlling mosquitoes while they are in their larval stages, for two primary reasons. Firstly, larval control is much more efficient than adulticiding – it is possible to treat larval mosquitoes in very high concentrations in rearing ponds, while adult mosquitoes tend to disperse soon after emerging over a much wider area. Secondly, biological larvicides such as Aquabac 200G are species-specific, affecting only aquatic members of the Order Diptera, which includes mosquitoes, and black flies. The alternative to larviciding is adulticiding using pesticides such as malathion and resmethrin which are broad-spectrum insecticides, with the ability to kill beneficial insects as well as pests, and can also be toxic to vertebrates including fish, birds and mammals. The City of Revelstoke & Electoral Area ‘B’ nuisance mosquito control program does not have an adulticiding component.

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Aquabac 200G (PCP 26862, a.i. 2.86%) is the trade name of the biological mosquito larvicide used in the City of Revelstoke & Electoral Area ‘B’ nuisance mosquito control program. The active ingredient of this product is the bacterium Bacillus thuringiensis var israelensis (Bti) which is formulated as a granule with crushed corncob as a carrier. The product is effective against mosquitoes and other members of the order Diptera in the larval stage, and is applied by hand, backpack blower or helicopter to standing water containing significant populations of mosquito larvae. Application rates vary from 3 to 20 kilograms per hectare (with the higher rates applied to polluted or highly organic water). In 2018, all site applications by hand/backpack blower and helicopter were made at a rate of five kilograms per hectare. Technicians monitored each larval development site at least once per week beginning in late- April and continuing into mid-August. When significant numbers of nuisance mosquito larvae were found, larvicide was applied either by hand, backpack applicator or helicopter, depending on the size of the site. This year, a total of 3,471.5 kg of larvicide was applied to 694.5 ha of habitat, compared with 5,953.0 kg of larvicide applied to 1,190.6 ha of larval development area in 2017. Of this, 104.5 kg was applied by hand or backpack blower to 20.9 ha of larval development habitat, and 3,367.0 kg was applied by helicopter to 673.6 ha of larval development habitat. A summary of all applications is given in Appendix I. Table 3 shows the historic application of granular larvicide. The amount of larvicide applied in 2018 was the second- highest in the past ten years, but considerably less than that applied in 2017. The high volumes of larvicide used was a direct result of the high levels of water present in larval development sites, primarily along the Columbia River (Figure 6).

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Table 3. Summary of granular larvicide (Bti) applications in Revelstoke & Electoral Area ‘B’ in recent years. Hand/Blower Helicopter Total Larvicide Area Larvicide Area Larvicide Area (kg) (ha) (kg) (ha) (kg) (ha) 2009 155.0 20.618 995.52 234.237 1,150.52 254.855 2010 53.65 8.994 1,538.5 357.4 1,592.15 366.394 2011 31.73 5.173 2,353.0 549.05 2,384.73 554.223 2012* 131.7 26.34 2,457.0 491.4 2,588.7 517.74 2013 83.0 16.6 2,143.4 428.7 2,226.4 445.3 2014 217.1 43.4 1,654.0 330.8 1,871.1 374.22 2015 106.75 21.35 1,674.0 334.9 1,780.75 356.25 2016 458.0 53.1 2,397.7 349.0 2,855.7 403.1 2017 738.4 147.7 5,214.6 1,043.0 5,953.0 1,190.6 2018 104.5 20.9 3,367.0 673.6 3,471.5 694.5 *2012 represents the first year where applications were conducted by BWP staff; prior to this, the program was delivered by DG Regan.

3.1. HAND APPLICATION OF BTI LARVICIDE Hand application of larvicide was initiated in on May 13th and continued until August 3rd. A total of 104.5 kg of Aquabac 200 G was applied by hand and backpack blower to 20.9 ha of larval development habitat (Table 4). The majority of the larviciding efforts occurred at sites RV9, RV13 and RV14, located along the Illecillewaet River.

Table 4. Summary of total hand applications of larvicide within each site in the City of Revelstoke & Electoral Area ‘B’ in 2018. Site Amount of Area Number larvicide (kg) treated (ha) RV3 6.0 1.2 RV6 1.0 0.2 RV8 2.0 0.4 RV9 25.0 5.0 RV13 29.5 5.9 RV14 23.0 4.6 RV19 7.0 1.4 RV23 11.0 2.2 Total 104.5 20.9

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3.2. HELICOPTER APPLICATION OF LARVICIDE Our company employed Summit Helicopters (formerly CC Helicopters Ltd.) for applications throughout the City of Revelstoke & Electoral Area ‘B’. We conducted four helicopter campaigns this year on June 8th, June 20th, June 29th, and July 23rd (Table 5). During the four helicopter campaigns, a total of 3,367.0 kg of Aquabac 200G was applied to 673.6 ha of larval development habitat. Sites requiring the largest amount of larviciding were areas along the Columbia River north and south of the airport runway, and the south shore of the Illecillewaet River near the confluence with the Columbia River (Table 6). Table 5. Summary of helicopter larviciding activities conducted in Revelstoke in 2018 by date. Amount of Area treated Date larvicide (kg) (ha) 8-Jun 891.8 178.52 20-Jun 873.6 174.72 29-Jun 891.8 178.36 23-Jul 709.8 141.96 Total 3,367.0 673.6

Table 6. Summary of total helicopter larviciding applications in each site in Revelstoke & Electoral Area ‘B’ in 2018. Amount of Area treated Site Number larvicide (kg) (ha) RV3 145.6 29.12 RV4 618.8 123.76 RV6 72.8 14.56 RV7 18.2 3.64 RV8 81.9 16.4 RV9 327.6 65.56 RV11 618.8 123.76 RV12 154.7 30.96 RV13 354.9 71 RV14 354.9 71 RV16b 72.8 14.56 RV19 191.1 38.24 RV23 354.9 71 Total 3,367 673.6

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4.0 PUBLIC OUTREACH During the 2012 and 2013 seasons, our technician in the Revelstoke area reported that they had noticed many properties with abundant mosquito habitats (containers and debris collecting water). They also reported that many of the residents that they spoke with were interested in learning about mosquito larvae and their life cycle. In 2014, our staff manned a public outreach booth at the Revelstoke Farmers’ Market. In 2015, we developed a brochure to distribute to landowners, to help them to reduce larval development habitat around their properties and reduce exposure to adult mosquitoes. A copy of the brochure is included in Appendix II. In 2018, we attended the Revelstoke Farmer’s Market on July 28 to answer questions, educate people about mosquito larvae and personal protection, and to distribute brochures.

5.0 LIGHT TRAPS Mosquito trapping is a useful component of a mosquito control program for a number of reasons. First, when traps are maintained in the same general areas annually over the period of record, they allow a comparison of relative numbers from year to year, which helps assess program efficacy. As well, since mosquito species composition is related to larval development habitat, the species composition and relative numbers of species can give a good indication as to where the mosquitoes may be rearing, and help identify new sites for control purposes. BWP Consulting Inc. staff deployed one mosquito trap within the City of Revelstoke. The trap is designed to attract mosquitoes with a black light. When the mosquitoes approach the trap, a fan sucks them into a jar. Technicians set the trap overnight, and collect the insects in the trap the next day. This year the trap was set approximately weekly on Pratico Road, near the extensive larval development habitat surrounding the Revelstoke Airport. The trap was initially set on June 14th and samples were collected on approximately a weekly basis until August 10th, when trapping ceased for the year. Insects collected in the traps were frozen and delivered to Kamloops. Mosquitoes were then separated from other insects caught in the trap, and identified to species.

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5.1. ANALYSIS OF 2018 LIGHT TRAP CATCH Although the mosquito trap was set on a weekly basis throughout the summer, only five specimens of Aedes vexans (a floodwater mosquito and a vicious biter) were captured. Numbers of adult mosquitoes were low throughout the Revelstoke area in 2018 compared with average years.

6.0 BIOLOGY OF MOSQUITO SPECIES COLLECTED Only one species was captured this year in Revelstoke. A brief discussion is given in the following subsections.

6.1. AEDINES AND OCHLEROTATUS SPECIES The genus Aedes includes all of the “floodwater” (i.e., laying their eggs on moist soil rather than on the water’s surface) species of mosquitoes in BC. Aёdes is the Greek word for disagreeable (Belton, 1983), and is an accurate reflection of these species in terms of both numbers and ferocity. Aedes species lay their eggs at the edges of waterbodies and rely on warm temperature and/or low oxygen level in flood-water to hatch. Most of the floodwater species peak in late June (following snowmelt and river flooding) and die in late summer. These mosquitoes over-winter as eggs. Mosquitoes that are viewed as nuisance species (i.e. present in high numbers and biting aggressively) are generally from this group, since large areas of habitat often become active with rising floodwaters and therefore huge batches of mosquitoes hatch at the same time. This is due primarily to the fact that eggs laid by most species remain viable for a number of years, and therefore egg concentrations in the soil can become very dense. Adults are generally short-lived (two to six weeks), and generally seek shade during hot summer days as they are prone to desiccation. Most species have only one generation each year, although some species are capable of two or more generations when conditions are suitable.

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6.1.1. Aedes vexans This mosquito species is considered the worst mosquito pest in Canada (Wood et al., 1979). Aedes vexans appear in extremely large numbers in almost any habitat where there are permanent, semi-permanent, or transient pools that have been flooded from snowmelt or rain. In the heat of summer, these mosquitoes can mature from the egg to adult in as short as five days, existing as larvae for as little as three days (Wood et al., 1979). Eggs of Aedes vexans can remain viable in the soil for many years, and because not all individuals hatch when submerged, multiple cycles of flooding and drying are needed for all eggs to hatch (Wood et al., 1979). Although most Aedes vexans adults will stay within a short distance of their larval development habitat, they are notorious fliers, capable of flying as far as 20 to 50 km or riding low jet streams for hundreds of kilometres (Belton, 1983). Specimens of Aedes vexans have been found carrying the western equine encephalitis (WEE) virus in Alberta, Saskatchewan and north-western United States (Belton, 1983).

7.0 CONCLUSIONS 2018 marked the seventh year that BWP Consulting Inc. conducted the City of Revelstoke & Electoral Area ‘B’ Mosquito Control Program. A strong effort in the early season to treat water following the early peak of the Illecillewaet, coupled with well-timed aerial applications to attack larvae in the Columbia-influenced habitat in June and July, resulted in an very few calls of concern and few adult mosquitoes captured this season. REFERENCES

Belton, P. (1983). The Mosquitoes of . British Columbia Provincial Museum Publication: Handbook No. 41.

Belton, P. (2007). British Columbia Mosquitoes as Vectors of West Nile Virus. BCCDC website: www.bccdc.org

Wood, D.M., Dang, P.T., & Ellis, R.A. (1979). The Insects and Arachnids of Canada, Part 6: The Mosquitoes of Canada, Diptera: Culicidae. Ottawa, ON: Biosystematics Research Institute.

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APPENDIX I. SUMMARY OF LARVICIDING ACTIVITIES CONDUCTED WITHIN THE CITY OF REVELSTOKE & ELECTORAL AREA ‘B’ IN 2018 WITH AQUABAC 200G

Date Site Amount(kg) Area(ha) Method 5/13/2018 RV3 2 0.4 blower 5/13/2018 RV3 2 0.4 blower 5/13/2018 RV13 3 0.6 blower 5/26/2018 RV19 2 0.4 blower 5/27/2018 RV9 3 0.6 blower 5/27/2018 RV19 2 0.4 blower 5/28/2018 RV13 2 0.4 blower 5/28/2018 RV6 1 0.2 blower 5/28/2018 RV13 3 0.6 blower 5/31/2018 RV9 2 0.4 blower 5/31/2018 RV14 2 0.4 blower 5/31/2018 RV14 2 0.4 blower 5/31/2018 RV23 2 0.4 blower 6/3/2018 RV19 3 0.6 blower 6/3/2018 RV9 3 0.6 blower 6/3/2018 RV23 2 0.4 blower 6/3/2018 RV8 2 0.4 blower 6/8/2018 RV11 154.7 30.94 helicopter 6/8/2018 RV9 72.8 14.6 helicopter 6/8/2018 RV4 154.7 30.94 helicopter 6/8/2018 RV7 18.2 3.64 helicopter 6/8/2018 RV19 81.9 16.4 helicopter 6/8/2018 RV23 81.9 16.4 helicopter 6/8/2018 RV13 81.9 16.4 helicopter 6/8/2018 RV12 81.9 16.4 helicopter 6/8/2018 RV14 81.9 16.4 helicopter 6/8/2018 RV8 81.9 16.4 helicopter 6/20/2018 RV11 163.8 32.76 helicopter 6/20/2018 RV4 163.8 32.76 helicopter 6/20/2018 RV9 109.2 21.84 helicopter 6/20/2018 RV14 109.2 21.84 helicopter 6/20/2018 RV23 109.2 21.84 helicopter 6/20/2018 RV19 109.2 21.84 helicopter 6/20/2018 RV13 109.2 21.84 helicopter 6/24/2018 RV23 3 0.6 blower 6/29/2018 RV11 154.7 30.94 helicopter 6/29/2018 RV4 154.7 30.94 helicopter 6/29/2018 RV13 72.8 14.56 helicopter

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Date Site Amount(kg) Area(ha) Method 6/29/2018 RV9 72.8 14.56 helicopter 6/29/2018 RV6 72.8 14.56 helicopter 6/29/2018 RV16b 72.8 14.56 helicopter 6/29/2018 RV23 72.8 14.56 helicopter 6/29/2018 RV12 72.8 14.56 helicopter 6/29/2018 RV3 72.8 14.56 helicopter 6/29/2018 RV14 72.8 14.56 helicopter 7/2/2018 RV9 3 0.6 blower 7/2/2018 RV13 3 0.6 blower 7/2/2018 RV23 2 0.4 blower 7/7/2018 RV23 1 0.2 blower 7/7/2018 RV9 4 0.8 blower 7/13/2018 RV9 4 0.8 blower 7/13/2018 RV9 1 0.2 blower 7/13/2018 RV14 1 0.2 blower 7/13/2018 RV3 1 0.2 blower 7/21/2018 RV9 1 0.2 blower 7/21/2018 RV9 2 0.4 blower 7/21/2018 RV14 1 0.2 blower 7/21/2018 RV14 1 0.2 blower 7/21/2018 RV23 1 0.2 blower 7/21/2018 RV3 1 0.2 blower 7/21/2018 RV13 1 0.2 blower 7/22/2018 RV9 2 0.4 blower 7/22/2018 RV14 2 0.4 blower 7/23/2018 RV13 91 18.2 helicopter 7/23/2018 RV3 72.8 14.56 helicopter 7/23/2018 RV11 145.6 29.12 helicopter 7/23/2018 RV14 91 18.2 helicopter 7/23/2018 RV9 72.8 14.56 helicopter 7/23/2018 RV23 91 18.2 helicopter 7/23/2018 RV4 145.6 29.12 helicopter 8/3/2018 RV13 17.5 3.5 blower 8/3/2018 RV14 14 2.8 blower

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APPENDIX II. MOSQUITO CONTROL BROCHURE

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