CHESTNUT-SIDED WARBLER 367 



DISTRIBUTION 



Rcmge. — Southwestern United States to central Mexico. 



Breeding range. — Grace's warbler breeds north to southern Utah 

 (Zion National Park) ; southwestern Colorado (Fort Lewis and 

 Pagosa Springs) ; and central northern New Mexico (Tres Piedras; 

 possibly Sierra Grande) . East to central New Mexico (Tres Piedras 

 and Mesa Yegua) ; western Texas (Guadalupe Mountains) ; and 

 northwestern Chihuahua (Colonia Garcia). South to northwestern 

 Chihuahua (Colonia Garcia) and southeastern Sonora (Rancho 

 Santa Barbara) . West to western Sonora (Rancho Santa Barbara, 

 Moctezuma, and Nogales) ; eastern central and western Arizona 

 (Huachuca Mountains, Tucson, Fort Whipple, Hualpai Mountains, 

 and Mount Trumble) ; and southwestern Utah (Zion National Park). 



Wvnter range. — In winter Grace's warbler seems to be confined to 

 a small area in central western Mexico, from central Jalisco (Bolaiios) 

 southeast to east central Michoacan (Patamban and Patzcuaro) ; and 

 west to south central Jalisco (Zapotitlan) ; occasional north to 

 northern Nayarit (Santa Teresa). 



Migration. — Very little information is available regarding the 

 migratory movements of Grace's warbler. Dates of spring arrival 

 are : Sonora — Mina Abundancia, April 11. New Mexico — Silver City, 

 April 20. Arizona — Santa Rita Mountains, March 15. The latest 

 date of one recorded at Albuquerque, New Mexico, is September 7. A 

 resident race occurs in Central America. 



Egg dates. — ^Arizona : 9 records. May 3 to June 27 ; 5 records, May 30 

 to June 8, indicating the height of the season. 



New Mexico : 2 records. May 22 and June 13 (Harris) . 



DENDROICA PENSYLVANICA (Linnaens) 



CHESTNUT-SIDED WARBLER 



Plates, 45, 46 



HABITS 



Many changes have taken place in the distribution and relative 

 abundance of many birds in different parts of our land since the settle- 

 ment of the country, owing to the changes wrought in the landscape 

 by man. The beautiful little chestnut-sided warbler is one of the 

 species that has benefited, flourished, and increased with the spread of 

 civilization. It seems strange that such a common, well-marked, and 

 familiar species, as we now know it to be over so much of northeastern 

 North America, should have been largely unknown by the early 



