Restoration Potential: This species uses a wide variety of woodlands and appears to respond positively to early successional stages of forest regeneration, so restoration potential would likely be high in a landscape of sustainable forest harvest or natural disturbance regimes. Sustaining riparian woodlands and chaparral habitats may be important to this warbler during migration and wintering. However much more detailed information is needed on the species biology to be conclusive about positive measures for restoration.
Preserve Selection and Design Considerations: May be area sensitive. Found to be positively associated with increasing stand area in Douglas-fir forests fragmented by timber harvest, however, no significant associations found with other measures of fragmentation (Rosenberg and Raphael 1986).
Management Requirements: Effects of management activities and disturbance are largely unstudied. Terborgh (1989) notes use of disturbed oak-woodland habitats on wintering grounds, but does not define type or extent of disturbance.
GRAZING: Effects of grazing activities are generally unknown. In pinyon-juniper, overstory removal to create pasture would be detrimental (Sedgwick 1987).
TIMBER HARVEST: Species is absent when forest overstory is removed. However, in an Engelmann spruce-subalpine fir forest, remained in interconnected forest remnants surrounding clearcuts four years after logging (8.30 singing males per 100 hectare; minimum width of residual stands was 413 +/- 59 meters) and occurred in similar densities to unlogged continuous forest (9.96 males per 100 hectares; Wetmore et al. 1985). The impacts of woodland fragmentation on productivity and survivorship are apparently unstudied. In pinyon-juniper habitats, tree removal may affect habitat use, as this warbler shows a preference for more mature trees in this habitat (Sedgwick 1987).
In northwestern Douglas-fir forests, however, shows a preference for younger stands, and densities are likely to be higher in young regenerating stands than in mature stands (Raphael et al. 1988, Carey et al. 1991, Huff and Raley 1991, Manuwal 1991). In the Oregon Coast Ranges, mean abundance was greater (P = 0.03) in unthinned stands than in stands commercially thinned five to fifteen years previous, where approximately 20 to 30 percent of the number of trees per hectare had been removed (Hagar et al. 1996). In even-age Douglas fir forests regenerating from clearcutting, Marcot (1985) found that mean densities were highest in shrub/sapling plots than in pole timber and medium sawtimber plots.
FIRE: Very little information available on relationship to burns. In a seasonal study of non-breeding bird abundances in ponderosa pine (PINUS PONDEROSA) forests on the Prescott National Forest, Arizona, Blake (1982) found the species restricted to unburned sites in fall and spring migration seasons.
Management Research Needs: Need detailed studies of response to habitat changes, including productivity and survivorship; monitoring of long-term changes in density in response to habitat alterations and succession; study of landscape and cumulative effects of habitat changes; rates of brood parasitism and behavioral response to parasitism. Information on migration and winter habitat use and ecology also needed.
Biological Research Needs: Nearly all aspects of the biology are poorly known. An excellent species for amateur and professional biologists to make significant contributions, especially as this warbler is relatively common and widespread and occupies a variety of woodland habitats. Studies are needed of behavior, breeding biology, wintering ecology, geographic variation in song, population dynamics, site fidelity, dispersal and migration.