Obligate Army-ant-following Birds: A Study of Ecology, Spatial Movement Patterns, and Behavior in Amazonian Peru. Ornithological Monographs No. 55. . Ornithological Monographs No. 55. This publication includes research on the Natural History of the birds and army ants, Resource use and species coexistence, Survival rates and population dynamics, and Nesting and reproduction. Includes knowledge about the army ants necessary to better understand the birds. Charts, graphs, illustrations, photographs. 67 pp.