- The Pacific Wren is a year-round resident in parts of its range, including southern interior BC. During the breeding season, its range extends to include central and northern interior BC and the Alberta foothills.1
- This species is strongly associated with old coniferous forests that contain old forest features including snags, upturned tree root masses, downed trees, and large-diameter trees.1
- The most suitable habitats for Pacific Wren include old western hemlock forests2,3 and/or closed conifer forest >200 years old (e.g., Douglas fir, western red cedar, etc.).4
- In BC, the Pacific Wren is often found within 5 m of streams <10 m wide, where they nest on stream banks under soil overhangs and upturned root masses.1,5,6
Response to Forest Management
- Clear-cutting and partial harvest reduce habitat suitability for the Pacific Wren3 for up to 40 years,7 however harvesting that retains high snag densities, slash piles, and upturned root masses may improve postharvest habitat quality.1,8
- Reduced densities of Pacific Wren near forest edges,9 forest stands <20 ha.1 and in narrow riparian buffers (avg. 13 m)10 suggest that this species is sensitive to fragmentation of late-seral habitats.
- Recommended retention patch anchors include large-diameter downed logs, large-diameter trees, and fallen trees with large rootwads. Slash piles and shrub cover protection (i.e., maintaining >60% shrub cover) are also considered likely to improve habitat quality within harvested stands.1,11
- The creation of small canopy gaps using selection cutting may be an appropriate strategy, but would require the targeted retention of important habitat features including snags, downed woody debris, large-diameter trees, and upturned root masses.6
- Cutblocks <10 ha that contain 10% dispersed retention may provide sub-optimal breeding habitat for Pacific Wrens, provided they are near mature or old forest.12
- Wide riparian buffers (e.g., >40 m), particularly along streams <10 m wide and including snags and downed trees, may represent suitable breeding habitat.6,10,11
- On landscapes managed within the area’s NRV, unfragmented forest stands larger than 30 ha and >80 years old (preferably >200 years old if available) are considered the most valuable habitats for conserving the Pacific Wren.1
- The majority of research on the Pacific Wren has been concentrated within coastal forests. Further research is needed to assess Pacific Wren responses to forest management in interior BC and determine whether similar habitat features are of equal importance to breeding pairs in these areas.