The cascading impact of emerald ash borer: effects of ash mortality on breeding bird communities in fragmented midwestern forests

Members of the genus Fraxinus make up nearly 10 percent of Ohio’s forested landscape. Emerald ash borer (Agrilus planipennis, EAB) an invasive wood-boring beetle of the family Buprestidae, has killed millions of ash trees since its accidental introduction from Asia. Ash is common in the fragmented forests of Ohio and other midwestern states, creating the potential for EAB to seriously impact the ecology of communities in these forests. The rapid generation of canopy gaps, snags and coarse woody debris that result from EAB invasion and ash mortality may create new niches and narrow or close existing ones, resulting in a cascade of direct and indirect ecological effects that may reverberate across trophic levels. Hence, EAB could have substantial impacts on forest structure and insect communities, ultimately altering habitat and food availability for native insectivores. We are documenting the effects of EAB-induced ash mortality on communities of breeding birds in 34 fragmented forest sites, representing a gradient of ash decline, across western and central Ohio. Specifically, our aim is to quantify the impact of EAB emergence, which may offer a distinct resource pulse for utilization by bark foraging birds. Additionally, we hope to dissect the relationships between EAB-induced ash mortality and fluctuations in abundance of breeding birds.