The bog was formed approximately 7,700 years ago following the retreat of the Champlain Sea.
The name 'Mer Bleue' refers to the blue mist that frequently forms over the bog during early mornings.
Sphagnum moss in the bog can hold up to 20 times its weight in water, acting as a giant natural sponge.
The peat layer in some parts of the bog reaches depths of up to six meters.
It is one of the largest bogs in southern Ontario and serves as a significant stopover for migratory birds.
The bog's acidic, low-oxygen environment prevents plant matter from decaying, which preserves ancient organic material in the peat.
It is a site of ongoing climate change research, with sensors monitoring carbon fluxes.
Mer Bleue Bog is a 3,500-hectare wetland ecosystem located within Ottawa’s Greenbelt, recognized as a Ramsar site of international importance. The primary visitor feature is a 1.2-kilometer wooden boardwalk that traverses a northern peat bog, a landscape typically found much further north in the Arctic. The bog functions as a carbon sink, sequestering large amounts of carbon dioxide in its deep layers of sphagnum moss. It hosts unique flora and fauna, including carnivorous pitcher plants, bog rosemary, and cranberries. The environment is highly sensitive, with acidic water and nutrient-poor soil that dictates specific plant life cycles. The area serves as a critical habitat for the endangered spotted turtle and several species of birds, such as the northern harrier and short-eared owl. The site remains managed by the National Capital Commission, which maintains the boardwalk to protect the fragile peat mat from human foot traffic.
The central observation deck on the boardwalk provides a wide panoramic view of the vast, open peatland.
Bring insect repellent as the marshy environment supports a high density of mosquitoes and biting flies.
Stay strictly on the wooden boardwalk to avoid damaging the rare and fragile peat mat ecosystem.
Visit with binoculars to better observe the bird species frequently found in the tall grasses and shrubs.
Do not step off the boardwalk; the bog surface is delicate and can be unstable or hazardous.
The boardwalk remains open year-round, but access may be restricted during winter months depending on snow accumulation and maintenance schedules.
No dogs, bicycles, or smoking allowed on the boardwalk to protect the ecosystem.
