LPRC 2025 Species Profile: Mountain Bluebird (Sialia currucoides)

WWF Canada

WWF-Canada’s 2025 Living Planet Report Canada (LPRC) shows the steepest average population decline of Canadian species yet — and one of the reasons is nature’s interconnectedness. Each species is part of a larger web, and when those links are broken, the impacts go beyond a single population. Read the full report for more species profiles.

The shocking cerulean of a mountain bluebird is a treat to the eyes. A robin-sized bird, it frequents backyards in central and western Canada, using nest boxes put up by nature enthusiasts.

Mountain bluebird in a field atop Cedar Butte, South Unit of Badlands National Park, United States.
© WWF-US / Clay Bolt

Read more about how wildlife are faring in different Canadian habitats, including the rocky, grassland and forests mountain bluebirds call home.

As their name suggests, mountain bluebirds prefer higher elevations and can be found breeding at elevations up to 2,700 metres. However, they also mix with species in flocks numbering over hundreds of individuals at lower elevations.

A handsome male mountain bluebird perches on a nest box. He is a striking blue against a blurred green backdrop.
Forestry and agricultural practices, as well as extreme weather caused by climate change, has led to a loss of suitable nesting sites and breeding habitat. Insecticide usage also impacts food availability for these striking cerulean insectivore. © Shutterstock

Mountain bluebird populations in Canada are falling

In Canada, mountain bluebird populations have experienced decadal fluctuations in abundance, leading to an overall decline of 60 per cent since 1970.

Mountain bluebirds are secondary cavity nesters, meaning they do not create holes in trees but use existing cavities to build their nests, such as those made by woodpeckers in the wild, or conservation nest boxes. Because of this, they are limited by a lack of suitable nest sites, combined with a loss of breeding habitat.

Insects are the primary food source for mountain bluebirds, especially during the breeding season. Their dependence on insects means that heavy applications of insecticides impact the quantity and quality of food available for chicks during the nesting season.

Extreme weather events such as unpredictable, heavy rainfall or early-season storms due to climate change also impact mountain bluebirds at all life stages, in addition to ongoing threats driven by forestry and agricultural practices.

While wildlife in Canada is declining, it is not beyond saving — if we act now. Click here to explore more wildlife population trends and solutions for recovery.