EASTERN TOWHEE NUMBERS INCREASE FOLLOWING DEFOLIATION BY GYPSY MOTHS

Bird populations and habitat were monitored each year before (1984 to 1986), during (1987 to 1988), and after (1989 to 1996) a major gypsy m oth (Lymantria dispar) outbreak in the eastern panhandle of West Virgi nia. Extensive tree mortality caused by repeated defoliations by gypsy moths resulted in the release of understory vegetation. Densities of Eastern Towhees (Pipilo erythrophthalmus) were significantly higher in the period following the gypsy moth outbreak. Both before and after t he outbreak, Eastern Towhee densities were higher in areas of the fore st with less overstory (particularly high canopy) and lower densities of live trees (particularly small trees). This indicates that not all forms of early successional habitat, specifically areas with a high de nsity of small-diameter trees, are suitable for species deemed as ''ea rly successional.'' Although the gypsy moth outbreak resulted in an in crease in the number of saplings, it also opened up the canopy and cre ated a dense layer of shrubs in many areas. Because Eastern Towhees fo rage and nest on the ground and in shrubs, the outbreak increased the amount of suitable habitat for this species. Given that densities of E astern Towhee are declining in the state, it is useful to document hab itat features that are important for sustaining towhee populations.