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[[handwritten]] [[circled]] 9 [[/circled]] [[/handwritten]]

behavior of either one or both species is not influenced by the presence or proximity of the other).
    The general social behavior of Panamanian Buff-throated Saltators is strikingly different from that of Panamanian Streaked Saltators in one important respect. The Buff-throated Saltators of this region are not openly very gregarious among themselves. Individuals of different pairs or family groups do not usually join or follow one another in a "friendly" manner, or associate with one another in flocks. But territorial neighbors do approach one another with some appreciable frequency. (This must be an "intrinsic" difference between the two species, as populations of the two species seem to be approximately equally dense in many areas of central Panama.) As far as I could tell, all or most of the encounters between neighboring Buff-throated Saltators are largely or completely hostile. Panamanian Buff-throated Saltators certainly perform many more overtly hostile behavior patterns than Streaked Saltators in the same areas. They seem to be particularly likely to perform many conspicuously aggressive [[strikethrough]] movements [[/strikethrough]] ^[[insertion]] [[handwritten]] PATTERNS [[/handwritten]] [[/insertion]], such as supplanting attacks and chases. 
    The account of Costa Rican Buff-throated Saltators in Skutch ( [[underlined]] op. cit. [[/underlined]] ) would suggest that their general social behavior is at least very similar to that of the Panamanian birds. But Skutch also says that Carriker and others found Buff-throated Saltators in small flocks in some parts of Central America. It is possible, therefore, that gregarious tendencies are among the factors that cause Panamanian Buff-throated Saltators to approach one another, even when the approaches are not obviously friendly. 
    Panamanian Buff-throated Saltators may be associated with individuals of other species, of other genera, somewhat more frequently than are Streaked Saltators (Moynihan, 1962a); but this may be largely due to the fact that other species, especially those species which form mixed flocks among themselves, are more common in the trees preferred by Buff-throated Saltators than in the lower vegetation preferred by Streaked Saltators.