The Comox Valley Regional District (CVRD) is continuing to investigate the mosquito infestation problem in the Saratoga/Miracle Beach area. A mosquito study was commissioned in 2016 for this area.  The report was completed in early 2017 and presented to the CVRD Electoral Areas Committee for consideration. The report results indicated moderate levels of larvae found over a widespread area. One area indicated the larvae numbers were elevated over the nuisance mosquito threshold. This hotspot was in a tidal channel in an upper bench of the Black Creek estuary. Mosquitoes were breeding in this area, and larvae were found from July to the end of August, meaning adult mosquitoes would be in the area throughout the entire summer until the cold fall temperatures killed them. 

 In 2017 the land owner was asked about mitigation measures for this area, but they were not in support of this change. This may not solve the entire problem in this area, but it may alleviate some of the pressure from mosquitoes within a 1 km radius of this spot. The CVRD is endeavoring to continue discussions with this land owner to see if they would reconsider their position on this matter.

This summer 2018, the Miracle Beach/Saratoga Beach area had a higher presence of mosquitos than other regions in the Comox Valley, especially the species that breed in brackish/salt water pools. The topography of this area is quite flat and naturally has a lot of standing water in areas such as dirt roads, areas surrounding the lagoons near the mouth of Black Creek, and in some of the naturally occurring wetlands. Typically we do not see an elevated number of mosquito larvae in natural wetlands as they often have a balance of predators that keep the mosquito larvae in check. However, there are occasionally imbalances that happen (also naturally) that cause this. 

Staff have since been in touch again with the environmental consultant and they have provided some initial feedback which includes recommendations that include site investigations to see what changes have occurred to some of the potential breeding areas, or expanding the initial survey area to see if there are other potential breeding areas that were missed in the initial study. The timeframe for mosquito breeding is approximately April to end of August, and some adults can live for up to several months after hatching, until the weather gets too cold in the fall/winter. Currently the timing window to conduct effective mosquito larvae sampling and analysis is over. However the good news is breeding this year is over and residents will see relief as the temperatures become cooler.

There are actions individual homeowners can undertake to reduce mosquito populations around the home, including removal of water-holding containers around the property, replacing water in bird baths and animal troughs, clearing clogged gutters, drains and ditches, and storing boats, canoes, wheelbarrows, such that they don’t collect rainwater. There are also options individual homeowners can consider to encourage mosquito predator control, including the installation of bat boxes and swallow nesting boxes in this area - see more information in the Frequently Asked Questions (FAQs).

Residents may continue to forward their addresses and contact information to help the CVRD assess this situation and see if the affected areas fall outside the past study area.  Email or call 250-334-6000. The CVRD will continue to work with the consultant on this issue and will continue to update the residents of the Saratoga/Miracle Beach community as further information becomes available.

Frequently Asked Questions (FAQs)

What is currently being done by the CVRD?

We are working to secure the services of the consulting firm who did a previous study in 2017. The consultant has familiarity with the area and knows the problems/concerns in order to provide up-to-date information to affected residents. The CVRD continues to monitor the concerns originating from this area in order to provide the consultant with additional data to review and provide future recommendations.

Are there any human health concerns such as West Nile Virus?

When the 2017 study was conducted there was no confirmed presence of this virus on Vancouver Island. CVRD staff have recently followed up with Island Health and there is no serious threat associated with mosquitoe-borne diseases at this time.

Has the CVRD conducted a spraying program in the past to control mosquito infestations?

In checking our records over the past 10 years we have not done this. Options for mosquito control are limited due to the widespread sources of mosquito breeding habitat in the Saratoga Miracle/Beach community and the environmentally sensitive salt marsh ecosystems located in the area.

Can larvicides (an insecticide that is specifically targeted against the larval life stage of an insect) such as Bti be applied?

During the spore-forming stage of its life cycle, the Bti bacterium produces a protein crystal which is toxic only to mosquitos. Bacillus thuringiensis subspecies israelensis (Bti) bacteria is found in soil and is used as a larvicide to kill larvae before they can grow into adult mosquitos that can bite people. Bti has been used for mosquito control for more than 30 years. The 2017 study indicates if the problem of nuisance mosquitoes persists in coastal areas in the Comox Valley, and all other controls have been attempted, then the use of Bti as part of an integrated mosquito management program should be further considered. 

What is the status of the CVRD bat boxes?

All three bat houses that were installed by the CVRD in Driftwood Park appear to have resident bat populations residing in them. We are very encouraged with these results.

How far can these mosquitoes fly?

Research indicates that flight travel can be up to 2kms or further depending on wind conditions.

As a resident what can I do?

The CVRD has provided links of the 2017 study to residents and to the Saratoga and Miracle Beach Residents Association (SAMBRA). The study includes recommended measures that residents can undertake to try and mitigate some of their mosquito problems and concerns - see page 27 onward. Some measures include installing bat boxes and bird houses, removing standing water or participating in a larvae sampling survey.