Blue-gray Gnatcatcher

Polioptila caerulea

Blue-gray Gnatcatchers inhabit the canopies and understories of mature deciduous woods in upland and bottomland forests. They seem most prevalent in oak-hickory forests in moist situations near habitat edges (Ellison 1992). They have been reported most frequently in woodlands exceeding eight hectares in size or along riparian corridors that are at least 30-60 meters wide (Peterjohn and Rice 1991). They actively glean insects from leaves and small branches and occasionally rush after flushed prey.

Code Frequency

Blue-gray Gnatcatchers are reasonably easy to detect by their distinctive, wheezy calls and their habit of conspicuously flittering about. They are often seen in pairs, which Atlasers recorded as probable breeding. Blue-gray Gnatcatchers superbly camouflage their nests with bits of bark and lichen. Nests can often be found, however, by watching the adults. As with many species, the ability to confirm breeding of Blue-gray Gnatcatchers appeared to relate to their abundance in a particular block. There were likely fewer birds in many of the blocks in which they were found but not confirmed.

Average Number of Birds / 100 stops

Distribution

Blue-gray Gnatcatchers were distributed statewide. However, probable or confirmed breeding observations were mainly associated with the most-forested regions. This association with forests explains their absence from the most intensively-farmed regions of the state: the Mississippi Lowlands and much of northern Missouri. They were solidly distributed throughout the Osage Plains and much of the western Glaciated Plains natural divisions.

Abundance

Blue-gray Gnatcatchers were most abundant along the Arkansas border and through the eastern Ozarks, which matches the distribution of forest cover in the state. Few were detected in northern counties.

Phenology

Blue-gray Gnatcatchers arrive in the south at the beginning of April and about a week later in the north (Robbins and Easterla 1992). Nesting behavior commences soon after arrival. Ellison (1991) reported that in the southeastern United States the earliest-nesting Blue-gray Gnatcatchers had second broods. This may account for the late Atlas observations.

Notes

Brown-headed Cowbird parasitism of Blue-gray Gnatcatchers was reported in only one out of 101 blocks. Brood parasitism of Blue-gray Gnatcatchers varies regionally from 82 percent in California to 4 percent in Vermont (Ellison 1992).

Breeding Evidence

Reported in 806 (66.8%) of 1,207 blocks

Home|Lists of Illustrations and Tables|Preface|Acknowledgments|Introduction|The Natural Divisions of Missouri|Guide to Species Accounts|Index of Bird Accounts|Appendix A.|Appendix B.|Appendix C.|Appendix D.|Appendix E.|Literature Cited