Savannah Sparrow Passerculus sandwichensis
Flight call description A high, descending, sibilant "tsuh" (see Subspecies).
Fig.1. Virginia February 20, 1994 (MO).
Perched bird.
Similar species Shorter and more sibilant than Field Sparrow. Longer, higher, and more sibilant than American Tree Sparrow with less of an upward-arched sound. Much shorter than Le Conte's Sparrow. See descending seeps.
Behavior Primarily a nocturnal migrant but engages in redetermined migration. Gives flight call regularly while perched and in flight during the day and during nocturnal migration.
Subspecies "Ipswich" Sparrow (P.s.princeps) gives a flight call very similar to that of other races, but our limited sample size suggests it may tend to be a slightly higher, buzzier, "tszu" with a more muffled quality.
Spectrographic description Measured calls (N=16) were 57.1-85.7 (73.8) mS in duration and in the 6.1-11.1 (7.1-10.0) kHz frequency range. The frequency track was double-banded, descending, and upward-arched. One example showed very fine modulations with a spacing of 5 mS between humps and a depth of 100 Hz.