An analysis of forage behavior in relation to stratification of the avian fauna in a mixed association of Red Fir, Western White Pine and Lodgepole Pine

This study deals with the vertical conation in forage "behavior of the "bird population In a pure coniferous forest association. In addition, it is an attempt to investigate the concept that groups of organisms function in a protoplasmic manner and that life on this earth is a system of conscious or unconscious cooperation, with each organism being an apex of a functional hierarchy and also a foundation stone of many others; each organism is dependent on some other organisms but is also independent of a multitude of others. Food chains and webs are the sustaining factors for the ever-present but fluctuating pyramid of numbers. This study near Nordern, California, beginning July fourth and ending August first, 1951, shows that birds In a forest association will forage in a stratified system in with the height of vegetation levels and where their favorite or most abundant food is located. This paper will Include stratal foraging behavior, an index census of numbers of individuals per species and an annotated checklist of the birds encountered during the study.