NEST-SITE CHARACTERISTICS OF RED-BELLIED AND RED-HEADED WOODPECKERS AND NORTHERN FLICKERS IN EAST-CENTRAL OHIO

In order to understand more clearly what factors limit the reproductive success of primary cavity-nesting birds, it is important to examine and compare the nest-site characteristics of sympatric species in a variety of forest and woodland habitats. To add to the data already available on various woodpecker species in eastern and central North America, several nest-site and habitat characteristics were compared and quantified for 46 red-bellied woodpecker (Melanerpes carolinus), 26 red-headed woodpecker (M. erythrocephalus), and 44 northern flicker (Colaptes auratus) nest cavities. Flicker nest cavities had larger entrances and were located lower in trees than were red-bellied and red-headed woodpecker cavities. Red-bellied woodpeckers excavated fresh nest cavities surrounded by bark in living trees significantly more often than flickers and red-headed woodpeckers. Red-bellied woodpecker cavities were also located in limbs angling downward more often than those of flickers and red-headed woodpeckers, although the difference in frequency was not significant. The compass orientation of nest cavities was random in all species. Red-bellied woodpeckers nested in forested areas with abundant ground vegetation more frequently than did flickers and red-headed woodpeckers. The continued existence of northern flickers and particularly red-headed woodpeckers in the Unglaciated Plateau region of Ohio is probably dependent on the continued existence of large dead trees in the region.