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Birds of the pacific northwest
Birds of the pacific northwest











birds of the pacific northwest birds of the pacific northwest

New land management polices that will greatly accelerate fuel reduction activities throughout the Pacifi c Northwest, including use of prescribed fi re, are currently being undertaken with limited scientifi c information on the eco- logical consequences for bird communities. Where prescribed fi re is being used to restore fi re as an ecological process or more often for reducing potentially hazardous fuels, bird conservation objectives can be achieved as a secondary benefi t. In general, prescribed fi re is not being used for bird conserva- tion in this region. The most likely bird communities vulnerable to these changes are in low-severity, high-frequency fi re regimes that include the Douglas-fi r type, drier portions of the white fi r type, Oregon-oak woodlands and savannas, native grasslands and sclerophyllous shrublands. No studies exist that directly address how bird communities are affected by habitat changes from fi re suppression in this region. In general, there is a high turnover of species after high-severity fi res, with a shift primarily from canopy-dwelling to ground-, shrub-, and snag-dwelling species that mostly are not associated with other successional stages. The postfi re stand-initiation stage in this type supports a reasonably distinct avifauna compared to other successional stages, a phenomenon that has been documented for high-severity fi re regimes in other regions. Bird communities and effects of fi re are best known from the western hemlock type, which has a high-severity fi re regime. Seven of the types have a low- to moderate-severity fi re regime and fi ve have a high-severity fi re regime with fi re-return intervals that span several centuries. Fire regimes and fi re effects vary considerably within this region due to its diverse topography and climate. We describe fi re regimes, vegetation succession patterns, bird communities, and fi re effects on birds for 12 major vegetation types in the region. Information on how fi re affects birds is limited for the maritime Pacifi c Northwest, even though fi re is an essential process within natural vegetation communities throughout the region. We summarize information on fi re effects on major vegetation types and bird/fi re relations within the maritime Pacifi c Northwest, and pose management- related questions and research considerations. Resource managers face the challenge of understanding how numerous factors, including fi re and fi re suppression, infl uence habitat composition and animal communities.













Birds of the pacific northwest