Western Forest Birds

Restoring Natural Cycles for Forest Health

Bullock's Oriole by Jim Merritt/Macaulay Library

Status: Stable overall, but with warning signs

a graph showing steady population trends in 46 species of western forest birds, green line, and steep declines in 3 tipping point species, red line, since 1970

The overall population for the western forest birds group is much the same as it was 50 years ago, aided by protected habitats. But since reaching recent highs in the early 1990s, western forest birds have declined by nearly 20%.

  • Almost half of this group (19 species) currently have declining population trends.
  • Five species have lost more than half of their population since 1970, including Tipping Point species such as Pinyon Jay and Rufous Hummingbird with poorly understood life cycles. More science is needed to identify the drivers of their declines.
  • Recent declining trends among Oak Titmouse, Williamson’s Sapsucker, and other birds appear to be associated with the disruption of natural disturbance patterns such as fire cycles. 

Birds Are Declining Where Western Forests Are Stressed 

two maps of the Pacific Northwest, comparing bird trends and forest health
Bird declines in forests that have departed from historic cycles. According to population trends generated by eBird data, bird numbers in the Pacific Northwest tend to be declining (browner colors, map at left) in forests that have departed from historic conditions and are most in need of disturbance restoration (redder colors, map at right). Sources: Cornell Lab | eBird data 2007–2019 (left map); DeMeo et al. 2018. (right map).

For most of the past 100 years, western forests have been managed to encourage conifer tree dominance and discourage fires. But for many centuries before the 1900s, fires were common on this landscape, both natural wildfires and intentional burns by Indigenous peoples.

Today those historic disturbance patterns that created a mosaic of conifer and broadleaf forest cover and successional stages have been disrupted, and large swaths of western forest landscapes have departed from their natural range of tree species and structural diversity.

These areas of forest departure from natural patterns are also hotspots for western forest bird declines. Furthermore, these compromised forests have very little resilience to the forces of wildfire and climate change, which puts greater forest landscape health and forest resources (such as water reservoirs) at risk of disaster. Investments in forest restoration can turn around this dim outlook for western forests and western forest birds.