Spread-Wing Postures and Their Possible Functions in the Ciconiidae

IN two recent papers Clark (19'69) and Curry-Lindahl (1970) have reported spread-wing postures in storks and other birds and discussed some of the functions that they may serve. During recent field studies (1959-69) of all 17 species of storks, I have had opportunities to observe spread-wing postures. in a number of species and under different environmental conditions (Table i). The contexts in which these postures occur shed some light on their possible functions.