The natural wealth found in Ontario’s biodiversity shaped our history, identity and economy. Our natural environment improves our overall health and well-being and gives us:

  • clean air and water, farming land, food, timber and renewable energy
  • opportunities for outdoor recreation and enjoyment

In Ontario, we are surrounded by many kinds of plants and animals. They inhabit a variety of ecosystems, such as forests, lakes, wetlands and prairies. This spectrum of life is what we call biodiversity.

There are three levels of biodiversity:

  1. genetic diversity – the variety of genetic information found in plants, animals and micro-organisms
  2. species diversity – the variety of species
  3. ecosystem diversity – the variety of habitats, ecological communities and processes

Why conserve biodiversity

All species, including humans, depend on each other to survive. This means that threatened or endangered species can put the survival of species that rely on them at risk.

By conserving biodiversity, we can help:

  • reduce disruptions in the food chain and habitats
  • safeguard our health, communities and economy
  • protect and recover species at risk

What we’re doing

We are working hard to protect our province’s rich variety of life and ecosystems.

To achieve this, we:

What you can do

You can help protect Ontario’s many species of plants and animals – and where they live.

Become a citizen scientist

Keep track of biodiversity in your own backyard and share what you learn with us.

Plant a pollinator garden

Plant local flowering species. Butterflies like yellow, pink, orange and purple flowers. Monarch butterfly larvae need milkweed to survive – collect seeds and sow them in your garden. Get more tips on how you can help pollinators in Ontario.


Be green and participate in or organize a clean-up for a park, ravine, or river in your area.

Grow native species

Plant native trees and plants wherever you live.

You can:

Watch out for invasive species

Invasive species like giant hogweed, zebra mussel and garlic mustard can take over the territory of other species.

If you find invasive species, you can:

Explore and learn more

Get outside and discover biodiversity.

You can:

To learn about Ontario’s biodiversity, you can:

Reduce your ecological footprint

A lot of biodiversity is lost because of human actions. To reduce your ecological footprint and help conserve biodiversity:

Reduce the risk

Ontario has more than 190 species at risk of becoming extinct including the Atlantic salmon, Chimney swift and Butternut tree. Learn about species at risk in Ontario Visit: ontario.ca/speciesatrisk

Buy local products

Find a market near you at Farmers markets in Ontario to buy local fruit, vegetables, meat and other products

Spending money on local products can:

  • help support rare and heirloom species
  • lower greenhouse gases caused by shipping food
  • boost your local economy

Threats to biodiversity

Although Ontario is rich in natural resources, plants, animals and their habitats face threats from:

  • habitat loss
  • invasive species
  • population growth
  • pollution
  • unsustainable use of natural resources
  • climate change

We have a shared responsibility to conserve biodiversity in order to maintain our quality of life, now and in the future.

Habitat loss

Loss of habitat is the biggest threat to Ontario’s biodiversity. The most serious habitat loss is happening in southern Ontario. Unfortunately, this is where some of the province’s rarest biodiversity is found, such as alvars and tallgrass prairies.

This habitat loss is mostly a result of:

  • new homes,
  • communities and
  • roads being built.

When a species faces habitat loss, their well-being and survival are put at risk, and this can negatively impact the entire ecosystem and the services it provides.

Invasive species

Any plant, animal or micro-organism that is introduced by human action outside its natural range is called an ‘alien’ species. An invasive species is an alien species that threatens the new environment it is in. It can also negatively impact people’s health and the economy.

A species that is invasive to Ontario can originate:

  • on another continent,
  • in a nearby country or
  • in another ecosystem within Ontario or the rest of Canada.

An invasive species may quickly reproduce and spread. It may infest, damage, displace, destroy, or cause significant ecological and economic damage to:

Once established, invasive species are extremely difficult and expensive to control and are usually impossible to eradicate. The ecological impacts of invasive species can be irreversible.

Population Growth

Ontario’s growing population (estimated at 13.1 million in July 2009) is one of the biggest pressures on our biodiversity.

  • As our population grows, more agricultural land and natural habitats will be converted to urban areas.
  • In general, population growth increases our total emission of greenhouse gases and pollutants, as well as our consumption of natural resources, which are already in high demand.
  • The people of Ontario, individually and collectively, need to work hard and together to reduce these pressures.

One way to measure the demand that we are putting on our natural resources is our ecological footprint.

  • The ecological footprint measures human demand for resources based on the amount of resources we use and wastes we produce.
  • The State of Ontario’s Biodiversity Report shows that humans are demanding more from the Earth than it can provide.


We release pollution into the:

  • air,
  • soil and
  • water.

Right now tens of thousands of pollutants are circulating through the Earth’s ecosystems, and many of them are having impacts on biodiversity. Pollution can disrupt ecological processes. Manufactured chemicals and other pollutants contribute to a variety of health issues in both wildlife and humans, including:

  • cancer,
  • birth defects,
  • behavioural changes and
  • chronic illness.

Some chemicals are known to deplete the ozone layer, which allows more ultraviolet (UV) radiation to reach the Earth.

  • UV rays can be especially damaging to ecosystems in the early spring, when vegetation is young and fish and frogs are laying their eggs in shallow water.
  • Humans and some food crops are also at risk from higher levels of UV radiation (for example, skin cancer in humans).
  • Light pollution is also a growing concern as our urban and industrial development has increased the amount of light falling on ecosystems and this impacts biodiversity— it can disorient migrating birds, for instance, or change amphibian behaviour and disrupt plant dormancy.

Unsustainable use of natural resources

Using natural resources faster than they can be replaced can affect genetic diversity, local species populations and ecosystems. This in turn can affect our economy and our wellbeing.

  • That is why Ontario has developed a number of programs to ensure sustainable harvests of fish and wildlife species and Crown forests.
    • These programs include education and enforcement components and have mostly been successful.
  • Unregulated, unsustainable and/or illegal harvest of some species, such as American Ginseng and protected reptiles, is still a concern.

Climate change

While climate change poses a serious threat to Ontario’s biodiversity, conserving biodiversity can help reduce the impact of climate change (reducing greenhouse gas concentrations) and help us adapt. For example, ecosystems such as forests and wetlands help reduce greenhouse gas concentrations. Some environmental impacts that we see as a result of climate change include:

  • Some trees and other plants are experiencing earlier leaf production, longer growing seasons, and damage, due to more spring freezes and expanded ranges of insect pests and pathogens.
  • Native species known to live in certain parts of the province are moving into new areas, resulting in new species interactions,
  • Reduced ice seasons are affecting biodiversity in coastal wetlands and nearshore habitat, reducing ice fishing opportunities, making food less available for polar bears, and rendering shorelines more susceptible to damage from extreme storm events in winter.
  • Lyme disease, a bacteria spread by some species of tick which once had limited range in Ontario due to temperature, is emerging as a serious health risk in new areas.
  • Fire seasons have ended later in the year over recent decades, resulting in overall longer fire seasons, and lightning-caused fires in the northwest have increased.
  • Increased frequency of extreme weather and changing precipitation patterns are creating more frequent low and high water level situations in Ontario, resulting in increased requests for provincial disaster assistance and associated costs.