Common Yellowthroat Geothlypis trichas
Flight call description An abrupt, low, electric buzzy "bzzt".
Fig.1. Maryland September 19, 1994 (MO).
Perched bird.
Similar species Usually distinctive, but some variations similar to Hooded or Canada Warblers. Kirtland's Warbler may also be similar. See buzz calls.
Behavior Primarily a nocturnal migrant but engages in a modified redetermined migration low through the bushes. Gives flight call regularly while perched and in short flights during the day and during nocturnal migration. Also intersperses flight calls with flight song occasionally during the day.
Spectrographic description Measured calls (N=12) were 45.6-65 (53.1) mS in duration and in the 3.4-9.5 (4.8-8.5) kHz frequency range. The frequency track was single or double-banded, often with the upper band less prominent toward the end, and often with a lower-frequency "tail" at the beginning. Calls were modulated with 4-7 (5.5) humps with a spacing of 7.6-9.5 (8.3) mS and a depth of 1.1-2.2 (1.6) kHz. Some presumed Common Yellowthroat nocturnal calls (e.g., Fig.11) differ from diurnal calls in that they lack modulations.