Pest Control


The City of Dauphin works cooperatively with the Province of Manitoba to lower the risk of West Nile virus in our community.  The Province has established mosquito traps in multiple locations in Dauphin, and monitors the number of Culex Tarsalis mosquitoes caught in those traps on a weekly basis.  Most mosquitoes do not carry WNV and in Manitoba, the main carrier of the virus is the Culex mosquito, which is usually less common than other mosquito types. The City will work in conjunction with the Province to ensure that larviciding is carried out in accordance with larvae and mosquito trap counts during this period. Please click September 4 – 10, 2016 Mosquito Trap Count to view the most recent results. This program is jointly funded with the Province of Manitoba, and is in place from May to August each year.

Please click West Nile Virus for more information from Manitoba Health.

The City of Dauphin has brochures for Lyme Disease and West Nile Virus located at City Hall – 100 Main Street S.


Tent Caterpillar (Malacosoma americanum)Hatched from egg masses around the same time as Poplars leaf out.  They feed on broadleaf trees for 5-6 weeks.  The older & larger larvae then come down from the now defoliated trees in search of more vegetation. By late June/July they are seeking out a protected place to spin a cocoon (the side of your house/under your eaves)  from which they will hatch in a few weeks.  They emerge a tan moth that live for 5 days and lay eggs on small twigs, which will hatch next spring.

Outbreaks last 3-4 years at intervals of 8-13 years apart.

Do not spray with Malathion.  As their natural predator is a grey fly that can be a nuisance to people, but does not bite.  This fly is necessary to manage the outbreaks of the Forest tent caterpillars.  The spraying of Malathion will kill this fly and may not kill all the larvae.

What you can do:

Remove any egg clusters from small twigs before they hatch.  Easiest to spot before trees leaf out.

Squish/Handpick and destroy any caterpillars within reach.  Sharp spray from a hose can aid in removing clusters higher up.  Avoid removing or damaging the bark on the trees as this can weaken them further.

Spray any remaining leaves with BTK while larvae are still small.  It can take up to 5 days to kill the larvae after being ingested.  Bacillus thuringiensis (BI) is a bacterium that is found naturally in the soil and is known to cause illness and death in various insect larvae, including caterpillars of pest species such as gypsy moth, spruce budworm, cabbage looper and Forrest Tent Caterpillar.  It is not harmful to humans, birds, pets, fish honey bees, beetles, spiders. etc.


We have cankerworms and tent caterpillars.  The tent caterpillars would be going after the poplars first and the cankerworms are on the elms, ash and maples. We may also have some isolated tent worm infestations as all these pests are with us at some level here and there but it is cankers that are at higher levels now.

The City of Dauphin uses the trained and licensed arborists at Dauphin Recreation Services to service trees located on City-owned, public property.  Dauphin Recreation Services will be spraying city boulevard trees for worms in the coming weeks. More information on the product being used, the method of spraying and the timing can be found on the DRS website using the following link:

Dauphin Recreation Services, on behalf of the City of Dauphin, will only spray trees located on public property and will NOT spray trees on private property.

Products can, however, be used on private property trees to control the worm population by homeowners or business owners, assuming the property application techniques are followed.

cankerworms FAQs


Lyme disease is caused by a bacterial infection that people can get from the bite of an infected blacklegged (deer) tick. Exposure to blacklegged ticks can occur from April to November. Adult blacklegged ticks are easier to find in the fall. They are smaller in size than the common dog (wood) tick, which does not transmit Lyme disease.  The City of Dauphin have Lyme Disease Brochures available at City Hall for pick up.

Please view Manitoba Health website for more information.