GAMBEL'S WREN-TIT 89 



sit side by side, facing in the same direction and so near together that 

 they appear as a single ball of feathers from which tails, wings, and 

 feet protrude — an appearance that is not accidental but is produced 

 by fluffing, spreading, and interlacing the body feathers to such a 

 degree that when the heads are turned to the outside and buried under 

 the scapulars a single ball remains without so much as a line of 

 separation. This arrangement of the feathers is an active process 

 involving both movements of the feathers by the muscles that control 

 them and manipulation of them with the bill. Usually the birds sit 

 so low that the body feathers touch the perch and partly conceal the 

 toes, but sometimes the bodies are well above the perch and then 

 one can see that the inner leg of each bird is drawn into the feather 

 mass and the weight supported on the outside leg. The angle of the 

 leg to the body suggests that the two birds are braced against each 

 other. In the wild the roost is a horizontal branch within the crown 

 of a bush. The same roost is used frequently but not necessarily on 

 successive nights. 



The fighting between adjoining pairs that takes place during bound- 

 ary disputes rarely deserves the name. The head feathers of the 

 contestants are raised, the long tail cocked sharply up, the body 

 crouched and tense. Each bird eyes its opponent and shifts its posi- 

 tion or perch as if sparring for an opening. One or more may utter 

 a staccato ter ter or a continuous pit. This action may go on for only 

 a moment or for 15 minutes or longer. If it is prolonged one bird 

 may fly at the other, but the latter makes a quick shift and is a foot 

 or two away when the attacker reaches the empty perch. This con- 

 tinues as the opponents move rapidly through a bush, or along the 

 boundary or back and forth across it. Sometimes the pursuer becomes 

 the pursued. Rarely, the combatants fly at each other and momen- 

 tarily flutter through the brush or on the ground, bills clicking and 

 wings striking. Eventually one pair, usually the invaders, works 

 back toward the center of its territory, and the other soon does like- 

 wise. The defending male usually sings, the invader sometimes does. 



Wren-tits are persistent in scolding the California jays, which enter 

 their territory during the breeding season. When a jay is discovered 

 the pair circle or follow it, constantly hopping about and uttering a 

 krrring sound until the jay moves on out of their territory. The jays 

 seem quite indifferent, but I found this habit useful in two ways. One 

 was in marking the territory of a pair by where they began and 

 ceased to scold jays. The other was to attract marked birds I wished 

 to identify to a given point by putting up a mounted jay. This ruse 

 worked only for a short time, but it did enable me to learn the identity 

 of several individuals. 



Various actions of the wren-tit disclose the approximate location 



