Key Takeaways

• Blacklegged ticks, also called deer ticks, are tiny parasites with four life stages: egg, larva, nymph, and adult.
• Infected blacklegged ticks can transmit Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease.
• Milder winters, longer growing seasons, expanding wildlife populations, and migratory birds are helping ticks spread across Ontario.
• Naturalized landscaping can create moist, shaded habitats where ticks survive, particularly around leaf litter, tall grass, shrubs, and dense vegetation.
• Ticks commonly gather along woodland edges, trails, fence lines, ravines, stormwater ponds, and other transition zones where people and wildlife cross paths.
• Effective tick control uses inspection, habitat management, monitoring, and targeted treatments based on Integrated Pest Management principles.

Ticks have become one of the fastest-growing pest concerns across Ontario. Once considered a problem mostly found in heavily wooded or rural areas, blacklegged ticks — commonly known as deer ticks — are now turning up in suburban neighbourhoods, parks, commercial properties, school grounds, golf courses, walking trails, and even residential backyards.

This shift is more than an inconvenience. Blacklegged ticks can carry bacteria and other pathogens capable of causing serious illnesses, including Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease. As tick populations continue to expand into new regions of Ontario, protecting people, pets, employees, customers, and visitors has become an important part of responsible property management.

At GreenLeaf Pest Control, we believe the most effective approach to tick control begins with education, proactive prevention, and science-based Integrated Pest Management (IPM). Whether you own a family home, manage a condominium, oversee a commercial campus, or operate an industrial facility, understanding why tick populations are increasing — and what you can do about it — is the first step toward reducing your risk.

Why Are Tick Populations Increasing in Ontario?

Many people assume there are simply “more ticks than there used to be,” and they’re right. The increase isn’t caused by a single factor, but by several environmental changes working together to create ideal conditions for ticks to survive, reproduce, and spread.

Milder Winters Mean More Ticks Survive

Historically, Ontario’s long, cold winters naturally reduced tick survival. While freezing temperatures alone don’t eliminate ticks — they often survive beneath insulating leaf litter and snow cover — extended periods of extreme cold once helped limit their numbers.

Today, milder winters and longer growing seasons allow more ticks to survive into spring and stay active later into the fall. In some parts of Ontario, blacklegged ticks can even become active during winter whenever temperatures rise above freezing.

This longer period of activity increases the likelihood of people and pets encountering ticks throughout much of the year.

Expanding Deer and Wildlife Populations

Despite their name, deer ticks don’t rely exclusively on deer. White-tailed deer play a crucial role by transporting adult ticks across large distances and helping establish new populations, but ticks feed on a wide variety of wildlife, including:

• White-footed mice
• Chipmunks
• Squirrels
• Rabbits
• Raccoons
• Foxes
• Coyotes
• Songbirds
• Domestic pets

Migratory birds are particularly effective at introducing ticks into new geographic areas — a single bird can carry attached ticks hundreds of kilometres during seasonal migration, allowing populations to establish far beyond their original range.

As urban development increasingly overlaps with natural habitats, wildlife is moving more freely through residential subdivisions, parks, ravines, and commercial properties — bringing ticks along with it.

Natural Landscaping Creates Excellent Tick Habitat

Across Canada, there’s been a welcome shift toward environmentally friendly landscaping. Naturalized gardens, pollinator habitats, rain gardens, native plantings, reduced mowing, and wooded buffer zones all provide important ecological benefits.

However, these same features can unintentionally create ideal habitat for ticks, which thrive in environments that are:

• Moist and humid
• Shaded
• Protected from direct sunlight
• Rich in leaf litter
• Surrounded by tall grasses or dense vegetation

Unlike mosquitoes, ticks can’t fly or jump. Instead, they climb onto grasses, shrubs, or low vegetation and wait with their front legs extended — a behaviour known as questing. When a person or animal brushes against the vegetation, the tick quickly attaches and begins searching for a suitable feeding site.

Naturalized landscapes often provide exactly the humidity and ground cover that ticks need to survive. This doesn’t mean environmentally responsible landscaping should be avoided — it simply means these spaces require thoughtful management through habitat modification, routine monitoring, and targeted Integrated Pest Management.

Reduced Cosmetic Pesticide Use

Over the past two decades, Ontario has significantly reduced the use of cosmetic pesticides on residential lawns and landscapes. These changes have provided important environmental benefits and encouraged more sustainable landscaping practices.

However, one unintended consequence has been a reduction in incidental control of outdoor pests, including ticks. Years ago, broad-spectrum lawn treatments sometimes suppressed tick populations even when ticks weren’t the intended target. Today, those incidental reductions occur far less frequently.

Professional tick control programs work differently. Rather than relying on routine blanket applications, they use carefully targeted treatments based on inspection findings, tick biology, habitat conditions, and Integrated Pest Management principles.

More Time Outdoors Means More Tick Encounters

Canadians are spending more time outdoors than ever before. Walking trails, conservation areas, cycling paths, outdoor fitness spaces, dog parks, cottage properties, and backyard entertaining have all become increasingly popular.

Commercial properties are changing too. Many office campuses now feature:

• Walking paths
• Outdoor seating areas
• Employee wellness spaces
• Stormwater ponds
• Naturalized landscaping
• Woodland buffers
• Recreational green spaces

These amenities improve employee well-being and property aesthetics, but they can also increase opportunities for tick exposure if vegetation isn’t properly managed. For property owners and facility managers, tick management is becoming an important part of maintaining a safe outdoor environment.

Understanding the Blacklegged (Deer) Tick

Although several tick species are found in Ontario, the blacklegged tick (Ixodes scapularis) receives the greatest attention because it’s the primary carrier of Lyme disease in Central and Eastern Canada.

Understanding how this tick lives helps explain why prevention is so important.

What Does a Blacklegged Tick Look Like?

Blacklegged ticks are surprisingly small:

• Larvae are about the size of a grain of sand.
• Nymphs, responsible for many human infections, are roughly the size of a poppy seed.
• Adult females are approximately the size of a sesame seed before feeding, and become much larger afterward.
• Adult males are smaller, darker, and feed very little.

Because immature ticks are so tiny, many people never notice them until symptoms develop days or weeks later.

The Tick Life Cycle

Blacklegged ticks have a two-year life cycle with four stages:

• Egg
• Larva
• Nymph
• Adult

Each stage requires a blood meal before progressing to the next. Larvae typically feed on small mammals and birds; nymphs feed on a wider range of wildlife, pets, and humans; and adults commonly feed on deer but will also attach to dogs, cats, and people. A tick usually remains attached for several days while feeding before dropping off to continue its life cycle.

Because ticks spend much of their lives hidden in vegetation rather than on hosts, reducing suitable habitat is one of the most effective long-term management strategies.

Where Are Ticks Found?

Many homeowners assume ticks only live deep in forests. In reality, they’re most commonly encountered along the transition zones where people and wildlife interact. High-risk areas include:

• Woodland edges
• Tall grass
• Shrub borders
• Leaf litter
• Walking trails
• Fence lines
• Stone walls
• Naturalized gardens
• Ravines
• Parks
• Cottage properties
• Golf course roughs
• Stormwater ponds
• Commercial campuses
• Schoolyards with adjacent natural areas

Ticks rarely survive in the middle of sunny, well-maintained lawns. Instead, they concentrate where shade, humidity, wildlife, and vegetation come together. Understanding these “hot spots” allows professional pest management companies to focus treatments where they’ll have the greatest impact while minimizing unnecessary pesticide use.

Closing Thoughts

Ticks are now a year-round concern across Southern Ontario, from downtown Toronto to the cottage regions further north. If you’d like a property assessment or want to learn more about our tick control programs, get in touch with GreenLeaf Pest Control or see the full list of areas we serve.

Stay tuned for Part 2, where we’ll cover practical tick prevention strategies for homeowners and property managers.

Frequently Asked Tick Questions

Why are blacklegged tick populations increasing in Ontario?

Blacklegged tick populations are increasing because milder winters and longer growing seasons improve their survival. Deer, birds, rodents, and other wildlife also transport ticks into new areas. Meanwhile, expanding development and naturalized landscaping create more places where people, wildlife, and suitable tick habitat overlap.

Where are ticks most commonly found on Ontario properties?

Ticks favour moist, shaded areas with dense vegetation or ground cover. Common locations include woodland edges, leaf litter, tall grass, shrub borders, walking trails, fence lines, stone walls, ravines, and stormwater ponds. They are generally less common in the centre of sunny, closely maintained lawns.

Are blacklegged ticks active year-round in Ontario?

Blacklegged ticks are most active from spring through fall, but they may also become active during winter thaws when temperatures remain above freezing, and the ground is not covered by snow. Tick awareness is therefore important throughout the year, particularly across Southern Ontario. Public Health Agency of Canada

Can ticks fly or jump onto people and pets?

No. Ticks cannot fly or jump. They climb grasses, shrubs, and other low vegetation, then wait with their front legs extended. This behaviour, called questing, allows a tick to grab onto a person or animal that brushes against the plant.

What diseases can blacklegged ticks transmit in Ontario?

Infected blacklegged ticks can transmit pathogens that cause Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease. Not every tick carries a disease-causing pathogen, but their small size and often painless bites can make an attached tick difficult to notice. 

How can homeowners and property managers reduce tick activity?

Reducing tick activity begins with identifying and managing high-risk habitat. Leaf litter, tall grass, dense shrubs, shaded borders, and wildlife travel routes deserve particular attention. Professional tick control programs combine property inspections, habitat modification, ongoing monitoring, and targeted treatments instead of routinely treating an entire outdoor area.