AZURE BLUEBIRD 261 



SIALIA SIALIS FULVA Brewster 

 AZURE BLUEBIRD 

 HABITS 



The history of this bluebird is ve^ brief, for very little seems to 

 be known about it, as it has rarely been seen north of the Mexican 

 boundary. 



Under the name of Sialia sialis azurea Baird, William Brewster 

 (1885) writes: 



Three Bluebirds obtained in the Santa Rita Mountains [Arizona] in June are 

 doubtfully referable to this subspecies. One of the two males (No. 1855, F. S., 

 June 18) has the blue above of that greenish shade said to be characteristic of 

 azurea, but the other (No. 1856, F. S.), taken the same day, does not differ in this 

 respect from sialis, the tint of the blue being precisely the same. Both are peculiar 

 in having the under parts (excepting the usual dingy white space on the abdomen, 

 crissum, and tail-coverts) nearly uniform pale brownish-orange, paler and yellower, 

 in fact-, than in the female of sialis, and with scarcely a tinge of the usual deep 

 reddish-brown. This characteristic is not mentioned in descriptions of azurea, 

 nor do I find it in any of the dozen or more Mexican and Guatemalan examples 

 before me. The Santa Rita female (No. 1897, F. S., June 20), is still paler beneath, 

 as well as browner above than the female of sialis. All these specimens differ 

 further from S. sialis in having rather longer wings and tails, in this respect 

 agreeing with azurea. In the event of their proving distinct from the latter, 

 which seems probable, I propose for them the name fulva. Whether distinct or not, 

 the bird is new to Arizona, no form of Sialia sialis having been previously reported 

 from that Territory. 



It would seem from the above description that these Arizona 

 specimens are merely intermediates or hybrids (if we may use that 

 term with subspecies) between these two races of S. sialis, as they 

 show a mixture of the characters of both forms. Mr. Ridgway 

 (1907) used the name Julva in the main text of his Bulletin 50, but. he 

 apparently changed his mind on it, for, in a footnote on page ix 

 of the table of contents, he says: "This should be Sialia sialis azurea 

 (Baird). (See Addenda, p. 887.)" 



The 1931 Check-list says that the azure bluebird "breeds mainly 

 in the Transition Zone from the mountains of southern Arizona south 

 to Jalisco, Oaxaca, and Vera Cruz. Winters south to northern 

 Guatemala." 



Harry S. Swarth (1914) calls it "rare in summer in the high moun- 

 tains of extreme southern Arizona." He cites the record of the 

 Brewster specimens, mentions a specimen taken by Dr. A. K. Fisher 

 at Fort Huaohuea on April 30, 1892, and says: "The species is not of 

 regular or of common occurrence in either of these mountain ranges, 

 where Sialia mexicana bairdi is the common breeding bluebird; in 

 fact the above records are the only ones known to me, though the 

 region has been visited frequently by collectors." 



