This study describes and analyzes the vocalizations of the Townsend chipmunk (Eutamias townsendii) in Oregon. Tape recordings of calls were collected primarily from Forest Park in Portland (Oregon) during 1970 and 1971, and sonograms of these recordings were produced. Findings were compared with those of Brand (1970) who investigated E. townsendii vocalizations in California. The prominent calls in the vocal repertoire of townsendii are the quist, the quirt, and the chipper. These calls all appear to be warning calls. The quist note is a a chevron-shaped (A) figure representing a sound which begins at a low frequency (1-2 KC), sharply rises to a peak at about 11 KC, and then drops sharply to the lower frequencies again. Quists are arranged into bursts, and bursts into sequences. The number of quists per burst and the frequency of the top of the note decreased significantly over time. The interval between burst increased significantly, while the interval between quists seems to increase over time. The variation in the quist rate and related character6istics between Oregon and California townsendii populations is probably a result of subspecific differences. There seems to be a trend in the sciurids from the specific vocal system (one definite meaning per call) of the forest dwellers towards the unspecific vocal systems of animal groups which live in the more open habitats. E. townsendii displays a specific vocal system in which each call seems to have a specific function.
| Identifer | oai:union.ndltd.org:pdx.edu/oai:pdxscholar.library.pdx.edu:open_access_etds-1717 |
| Date | 01 September 1971 |
| Creators | Warner, Greig Michael |
| Publisher | PDXScholar |
| Source Sets | Portland State University |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Dissertations and Theses |
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