Abstract
Knowledge of factors affecting song rates is important because biologists use song in estimating or monitoring bird populations. Perhaps for no other species have song censuses played such a major role in population assessment and management as for the Kirtland`s Warbler (
Dendroica kirtlandiz). In 1951, this endangered songbird was first censused within the known nesting range, which is restricted exclusively to Michigan (Mayfield 1953). The entire population was censused again in 1961 (Mayfield 1962) and every year after 1970. This information has been used to assess the response of this species to various management techniques (e.g., Brown-headed Cowbird [
Molothrus ater] control). Recruitment to the population has been estimated by assuming that all singing males were paired (Mayfield 1975, 1983; Walkinshaw 1983; Probst, in press) and using known or inferred values for mortality rates, number of young fledged, and other demographic variables. Recently, Probst and Hayes (unpubl.) showed that a significant percentage of these singing males were probably unmated.
Keywords
Kirtland`s Warbler,
Dendroica kirtlandii,
song rates
Citation
Hayes, Jack P.; Probst, John R.; Rakstad, Don. 1986. Effect of mating status and time of day on Kirtland''s warbler song rates. The Condor 88:386-388