THE FOOD OF THE DIPPER (CINCLUS MEXICANUS SWAINSON) ON TWO WESTERN MONTANA STREAMS

Author

Patricia Ann Mitchell

Year of Award

1968

Document Type

Thesis

Degree Type

Master of Arts (MA)

Department or School/College

Department of Zoology

Abstract

The dipper or water ouzel (Cinelus mexicanus Swainson) inhabits mountain streams in western North America from Alaska to Panama, The food of this bird has been little studied, although many naturalists such as Ehinger (1930), and Muir (1894) listed field observations of dipper feeding habits. Unlike most passerine birds, the dipper dives beneath the surface of the stream in search of food, Vorhies (1921) reported that dippers appear to feed on the Plecoptera and the Ephemeroptera; Michael (1922) described an incident of a dipper eating a fish; Ehinger (1930) observed dippers eating salmon eggs and caddisflies, Bent (1943) states that such aquatic forms as caddisflies, mayflies, and fish are eaten. The only stomach analysis of dipper food is that of Bakus (1959), who lists stomach contents of two birds accidentally killed in summer, Nothing is known of the proportions of available food that are eaten or what factors govern the selection of food items by the dipper. My investigation deals with these questions—do dippers take food in proportions similar to those found in the stream? What factors are involved in the selection of food by dippers?

Recommended Citation

Mitchell, Patricia Ann, "THE FOOD OF THE DIPPER (CINCLUS MEXICANUS SWAINSON) ON TWO WESTERN MONTANA STREAMS" (1968). Graduate Student Theses, Dissertations, & Professional Papers. 12610.
https://scholarworks.umt.edu/etd/12610