Bird populations in Alberta’s foothills are declining this year due to a combination of habitat loss, climate change, and declines in food availability:
- Habitat loss and degradation, primarily from agricultural expansion and industrial development, is the single largest driver of decline for grassland and native bird species[1][2][3]. The conversion of native grasslands to cropland and monoculture agriculture, along with fragmentation from roads, oil and gas wells, and other infrastructure, removes critical nesting and feeding habitats for many birds[1][4][3].
- Drying of wetlands and lakes—linked to ongoing climate change—reduces insect populations, which are a main food source for aerial insectivores like swallows, further diminishing food availability[1][2][4]. Hotter, drier summers also lead to widespread nest failures among songbirds and cavity-nesting species such as tree swallows and mountain bluebirds[1][4].
- Changes caused by climate change—including earlier snowmelt and sudden spring storms—create "climate traps" that can result in birds returning too early, exposing them to harsh weather or food shortages[4]. Increased frequency of snow-free winters impacts prey populations (like voles), affecting raptors and other birds of prey[4].
- Agricultural chemicals and practices affect food webs. Pesticides reduce insect abundance, and certain livestock treatments reduce dung beetle populations, indirectly harming insectivorous birds such as swallows and burrowing owls[4].
These combined pressures particularly impact grassland, wetland, and aerial insectivore bird species, making their populations especially vulnerable and resulting in the notable declines observed this year in Alberta’s foothills[1][2][4].
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- https://naturealberta.ca/state-of-albertas-birds/
- https://centralalbertaonline.com/articles/grassland-bird-populations-declining
- https://albertawilderness.ca/issues/wildlife/sage-grouse/
- https://albertaviews.ca/the-wings-of-change/
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