NO. 7 FLOCKS OF NEOTROPICAL BIRDS — MOYNIHAN 97 



SLATE-THROATED REDSTART 



The social relations of slate-throated redstarts with individuals of 

 other species on the Volcan de Chiriqui are somewhat reminiscent of 

 the corresponding relations of silver-throated tanagers. 



Slate-throated redstarts are very brilliantly colored and very active. 

 They are probably more conspicuous visually than individuals of any 

 other species of the montane bush alliances, except the closely related 

 collared redstarts (see below). They do not, however, play a very 

 important role in most mixed montane bush flocks. 



On the western slopes of the Volcan de Chiriqui, slate-throated 

 redstarts are common below 6,000 feet, and also occur in smaller 

 numbers up to at least 7,000 feet. They occur in many different levels 

 of vegetation, from just above the ground to high in tall trees. 

 Throughout this wide range they join and follow, and are joined and 

 followed by, individuals of many other species; but none of these 

 reactions seems to be common enough to suggest that slate-throated 

 redstarts have a special interspecific preference for any other species, 

 or are the object of any special interspecific preference of any other 

 species. Slate-throated redstarts are certainly joined and followed 

 by individuals of other species relatively much less frequently than 

 are bush-tanagers or black-cheeked warblers, and join and follow indi- 

 viduals of other species relatively much less frequently than do 

 yellow-thighed finches, many furnariids, or Wilson's warblers. They 

 are joined by the undiscriminating Wilson's warblers relatively more 

 frequently than by yellow-thighed finches or furnariids. 



Associations between slate-throated redstarts and individuals of 

 other species also tend to be relatively brief and not very close, and 

 would thus appear to be essentially "casual." In the course of their 

 normal activities slate-throated redstarts and individuals of many 

 other species tend to encounter one another very frequently, and they 

 may stay more or less together for some time ; but the slate-throated 

 redstarts eventually become separated from the others without any 

 obvious signs of reluctance on either side. They probably do associate 

 with other species of the montane bush alliances relatively more fre- 

 quently than do silver-throated tanagers ; but they probably should not 

 be classified as regular members of the mixed montane bush flocks. 



Slate-throated redstarts are not very gregarious among themselves, 

 and it is relatively very rare to see more than one or two of them 

 associated with the same mixed flock at the same time. When they 

 are associated with mixed flocks, they probably produce an effect that 

 is not very different from that produced by Wilson's warblers. Slate- 



