28 U.S. NATIONAL MUSEUM BULLETIN 237 part i 



Territories once established were maintained almost entirely by the males of 

 both species. The female assisted in defense only when the nest or young were 

 threatened directly. * * * When a Pyrrhuloxia nest and eggs were examined 

 the female completely disappeared, but the male often stayed in the same tree and 

 sang vigorously. If young were in the nest, the male, and sometimes the female, 

 would fly around excitedly singing or giving their chatter call.* * * Territory 

 was maintained in three primary ways: combat, proclamation, and patrolling. 

 Combat, which includes both fighting and chasing, was noticed in both species, 

 but it was much more vigorous in the Pyrrhuloxia. An intruding bird would 

 be met, usually near the boundaries of the territory and either a fight or a chase, 

 and often both, would follow. In all cases the intruder was forced to leave the 

 area. If contact was made well within the territory, the intruder was much more 

 prone to take flight, resulting in a chase. If contact was made near the boundary, 

 then a fight was more likely to occur. For the most part, intrusions were made 

 only by males of adjoining territories. Unmated birds passing through the area 

 were generally tolerated, but an established bird never was. * * * 



Proclamation of territory consisted of intensive singing on the part of the 

 males of both species. It was most frequent during the early morning, when a 

 chorus of many birds could be heard. At this time singing would usually be 

 from a favored site within the center of activity of the territory. Occasionally 

 during the day competitive singing between males of the same species was heard. 

 This was equally common in the Cardinals and Pyrrhuloxias. The males sang 

 either in unison or alternated with each other. This type of song was most 

 common between males of adjoining territories. Competitive singing between 

 widely separated males was heard on only a few occasions. 



Patrolling was noted in both species; however, only the Pyrrhuloxia followed a 

 regular pattern. * * * After the initial singing in the morning the male would 

 make his rounds, singing a few songs in one bush and then in the next, until a 

 complete circuit had been made. He was never observed outside of the area * * *. 



Once the young are out of the nest, territorial defense and maintenance were 

 reduced, and they stopped entirely if it was late in the season. If a nest was 

 destroyed, territorial activity increased although it never reached the peak of 

 the initial activity. Individual pairs of both species were seen to make as many 

 as three attempts at renesting, with a recurrence of high territorial activity, if 

 their nests were abandoned or destroyed. 



Gould says that cardinals defend their territories only against 

 trespass by other cardinals and that pyrrhuloxias defend their areas 

 only against other pjTrhuloxias. In the 42 acres of the study area, 

 he reports that — 



territories of six Cardinals and ten Pyrrhuloxias were established * * *. The 

 total portion of the study area occupied by Cardinals was 54.5 per cent, wheras 

 that occupied by the Pyrrhuloxias was 60 per cent. Both species required a suit- 

 able amount of woodland within each territory. An average of 45 per cent of the 

 territory of each pair of Cardinals and 43 per cent of the territory of each pair of 

 Pyrrhuloxias included mesquite woodland * * *. Cardinals appeared to require 

 denser woodland in which to nest than did Pyrrhuloxias. An example of this was 

 the fact that, although Cardinals were occasionally seen and hearrl to sing from 

 an open mesquite patch, none established a territory there. One pair of Pyrrhulox- 

 ias, however, was able to establish a territory at this spot and raise one 

 family. This patch consisted of small and widely spaced mesquite trees with 

 much open, weed-covered ground between them. In other areas near Tucson, 



