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We examined factors affecting the nesting success of a migratory songbird, the Acadian flycatcher (Empidonax virescens), in loblolly pine plantations in the coastal plain of South Carolina, USA. From 1997–2000, we located and monitored 163 Acadian flycatcher nests in loblolly pine stands and corridors that were 18–27 years old. We used Mayfield logistic regression (Aebischer 1999, Hazler 2004) to model the effects of edge and stand‐level vegetation structure on nest daily survival rate. There was no evidence of an effect of edge on nest survival, but nest survival was positively related to the height of the deciduous subcanopy and to the density of shrub cover. Although Acadian flycatchers are generally regarded as habitat specialists requiring mature hardwood forests, our data suggest that pine plantations can support breeding populations, provided that a substantial hardwood component is present. We believe that maintaining multiple vegetation strata and increasing the length of harvest rotations would improve the habitat value of pine plantations for Acadian flycatchers and presumably other species more typically associated with deciduous forests. Maintenance of a corridor network, as practiced by some industrial forest managers, is one means of providing more mature forest habitat, thereby fostering higher nesting success. Concern that these corridors might act as ecological traps seems to be unwarranted in our study area. Corridors thus appear to be a valuable management tool for promoting wildlife values within the context of an industrial forest landscape.

Abstract:We examined the initial response of avian nest success to mechanical thinning, prescribed fire, and thinning/ prescribed fire combination treatments, designed to reduce fuel loads, at study sites throughout the continental USA as part of the National Fire and Fire Surrogate (FFS) Project. We modeled the daily nest survival of ground-, shrub-, tree-, and snag-nesting bird species to test for effects of: (1) overall treatment (2) specific treatment category (i.e., burn, thin, thin/burn); (3) time since treatment; and (4) study site. Of the 7 species examined, only 2 had top models that included effects of the FFS treatments, the remainder had either constant survival rates, or rates that varied only by study site. The Eastern Towhee had top models that included effects of treatment and study site, while the Red-bellied Woodpecker had top models that included effects of treatment category, time since treatment, and study site. All estimates of treatment, treatment category, and study site were statistically weak with confidence intervals including zero. The lack of clear response patterns observed in this study is likely a consequence of the variability inherent across forest types and taxonomic groups we examined. Forest managers should use our results cautiously and also be encouraged to facilitate opportunities for studies of avian nest survival as a function of fire-surrogate treatments that are regional specific, encompass longer time frames and larger spatial scales.

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