Timing windows listed are general approximations and vary by year and latitude. Consult Birds Canada for current survey data and regional reports.
Canada is crossed by four major North American flyways — the Pacific, Central, Mississippi and Atlantic — and is the primary breeding destination for billions of migratory birds each spring. Most species depart wintering grounds in Central America, the Caribbean, the Gulf Coast or South America between March and May, arriving at Canadian breeding sites by June.
Canada's Four Flyways
The flyway system is a broadly geographic concept describing the general corridors used by migrating birds, though individual species and populations move more specifically than the flyway boundaries suggest.
Pacific Flyway
This corridor runs along the BC coast and through the interior of the province. Shorebirds concentrate on tidal mudflats in the Fraser River Delta (Boundary Bay) during peak spring movement in late April and early May. Dunlin, western sandpiper, and semipalmated plover pass through in significant numbers. The Pacific Flyway also channels waterfowl through the Okanagan Valley and northern interior lakes.
Central Flyway
This route traverses the Prairie provinces, connecting wintering grounds in Texas and Mexico to nesting areas on the Canadian prairies and boreal forest. The Prairie Pothole Region — spanning southern Alberta, Saskatchewan and Manitoba — holds wetlands that are critical staging and nesting habitat for ducks, geese and shorebirds. Whooping cranes cross Saskatchewan during April–May, staging at Last Mountain Lake, the oldest bird sanctuary in North America.
Mississippi Flyway
This flyway funnels species from the Gulf Coast north through the Great Lakes and into Ontario and Quebec. Warblers, vireos and flycatchers cross Lake Erie and Lake Ontario in large concentrations during April and May. Long Point, Ontario is one of the most studied migration points on the continent, with continuous banding records maintained by Birds Canada since 1960.
Atlantic Flyway
This corridor connects the eastern seaboard from Florida to Quebec, Labrador and beyond. The Bay of Fundy, shared by New Brunswick and Nova Scotia, is globally significant for shorebird staging in autumn but also receives northbound shorebirds in May. The St. Lawrence River provides a spring waterfowl corridor for species moving toward breeding grounds in northern Quebec and Labrador.
Key Observation Sites
Point Pelee National Park, Ontario
A narrow peninsula extending into Lake Erie, Point Pelee is the southernmost tip of mainland Canada and concentrates migrating passerines during May. On peak mornings following favourable winds from the south, dozens of warbler species, thrushes, vireos and flycatchers can be found in the park's woodlands and marshes. Parks Canada manages the site; entry fees apply.
Last Mountain Lake, Saskatchewan
Designated a Ramsar Wetland of International Importance, Last Mountain Lake hosts large concentrations of sandhill cranes, Canada geese and tundra swans in April. The whooping crane staging period typically falls in late April. Environment and Climate Change Canada monitors crane numbers at this site annually.
Boundary Bay, British Columbia
The tidal mudflats of Boundary Bay, adjacent to the Robert Baker Bird Sanctuary, support some of the highest shorebird counts on the Pacific coast. Peak movement of western sandpipers occurs in late April to early May. Access is via Delta, BC; the area is managed under the South Coast Bird Conservation Region framework.
Spring Migration Timing (General)
- Early March: First waterfowl and geese northbound
- Late March – early April: Shorebirds arrive in southern provinces
- Mid-April: Loons return to boreal lakes; first warblers in southern Ontario
- Late April – mid-May: Peak passerine migration across central and eastern Canada
- Late May – early June: Late migrants (flycatchers, Blackpoll warbler) pass through
Common Loon Spring Movements
Common loons (Gavia immer) winter along Atlantic and Pacific coasts and move inland to boreal lakes as ice breaks up in April and May. They are highly fidelitous to breeding lakes and typically return to the same site each year. In British Columbia, loons stage on larger lakes during late April before dispersing to smaller breeding lakes when ice clears. Birds Canada's loon monitoring documents breeding productivity at hundreds of sites across the country.
Bald Eagle Spring Movements
Bald eagles that winter along major rivers in the Pacific Northwest move north along BC coastal waterways from February through April. In Ontario, eagles follow the shorelines of the Great Lakes, concentrating where fish are accessible through partially open ice. Their northward movement broadly coincides with waterfowl migration, and observation opportunities are best near large water bodies in March and April.
