Spatial patterns and dynamics are important components in understanding the relation between animals and their habitat, and how this relation changes over time. Methods for assessing spatial properties in bird populations are expensive, difficult, and intrusive, such as GPS tracking or capture–recapture, limiting our ability to measure these important characteristics. The Morisita Index and Ripley’s K function are both methods used to measure the distribution, clustering, and spatial organization of organisms in a given area. The goal of this paper is to demonstrate how these 2 simple methods can be applied in ornithology studies, based on simple and easily obtained data. To exemplify the application of both methods, I use coordinate data for Southern Lapwings (Vanellus chilensis) in southern Brazil over 2 different periods: the breeding and nonbreeding seasons. The analyses show that both methods obtain similar results and indicate aggregation among birds during both the breeding and nonbreeding periods. The Morisita Index was sensitive to changes in quadrat size while variations in Ripley’s K function were more difficult to interpret. Both methods have advantages and limitations that should be taken into consideration; nevertheless, the Morisita Index and Ripley’s K function can be important tools in studies of ecological spatial processes and patterns in birds.

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