Biologists have become increasingly concerned about declining populations of migrant songbirds. Much previous research and management has targeted breeding and wintering habitat; however, interest in migration stopover habitat has grown in recent years. In light of this, we examined bird habitat use at Iroquois National Wildlife Refuge with mist nets and visual transects and measured vegetation characteristics and fruit availability in early successional habitats during the past two fall migrations. Relationship between mist net and transect bird abundance varied between species and habitats, with significant positive relationships for Gray Catbirds and Song Sparrows in shrublands. There were no significant relationships between the two measures of abundance in the forest or for smaller species using shrublands, such as warblers. Bird abundance was generally greater in shrublands than early successional forests and bird diversity tended to be greater in more diverse shrublands. American Robin abundance was positively correlated with shrub cover and honeysuckle fruit abundance, while Song Sparrows preferred fields with more red panicled dogwood fruit and greater shrub species richness. These results will hopefully provide guidance to land managers in charge of providing habitat for fall migrant songbirds.
|Presenter:||Bradley Mudrzynski (Graduate Student)|
|Time:||11:15 am (Session II)|