Barred Owls Have Outcompeted Spotted Owls in California

A new study found barred owls dominate the same forest habitats, contributing to northern spotted owl declines.

Updated on Sept. 24, 2026 in Bird Watching

Bold vector editorial illustration of two owl silhouettes perched on stylized coniferous branches, representing habitat competition in dense forests. — A new study indicates that invasive barred owls have expanded their range in Northern California, directly outcompeting native northern spotted owls for essential forest resources. AI Illustration. Upload story photo >

Live Poll

Do you support the targeted removal of invasive species to protect endangered native wildlife?

Barred owls have expanded into Northern California and Oregon, occupying ranges 28-times larger than their native areas. Researchers determined that these larger, more aggressive birds compete directly for the same forest resources as northern spotted owls.

Why it matters

The study clarifies why northern spotted owl populations continue to drop even when suitable forest habitat is available. Understanding this competition is considered essential for developing effective recovery strategies for the spotted owl.

Barred owls now occupy an area in Northern California that is 28-times larger than their native range. Researchers utilized GPS trackers on captured birds to monitor movement patterns and evaluate habitat usage.

The players

Northern Spotted Owl

This species is a forest-dwelling owl whose population has seen significant declines due to habitat competition.

Barred Owl

This is a larger, more aggressive owl species that has expanded its range across the Pacific Northwest.

The details

By attaching GPS trackers to captured barred owls, researchers monitored their movements to confirm they favor the same forest environments as northern spotted owls. The data suggests that aggressive competition from the expanding barred owl population is a primary driver behind the decline of the spotted owl.

Barred owls began expanding into Oregon and Northern California during the late 20th century.
The new study regarding owl habitat usage was published on September 24, 2026.

Culture Shift

This study marks a significant shift in conservation strategies by providing empirical evidence for the necessity of owl management. It highlights how invasive species expansion permanently alters regional biodiversity and necessitates active intervention to preserve native wildlife.

Residents in Northern California may notice shifts in local bird populations as conservationists implement removal programs. These efforts are intended to stabilize the ecosystem by addressing the aggressive competition between these two owl species.

The takeaway

Wildlife experts now suggest that actively removing barred owls is likely necessary to facilitate a recovery for spotted owls. Protecting regional biodiversity often requires difficult management decisions to mitigate the impacts of invasive species.