NORTHERN MacGILLIVRAY's WARBLER 54] 



Salvador (Volcan de San Miguel, Volcaii de Conchagua, and Volcan 

 de Santa Ana) ; and Oaxaca (Tehuantepec). West to Oaxaca (Te- 

 huantepec) ; Michoacan (Patamban and Zamora) ; Colima; Sinaloa 

 (Mazatlan and Escuinapa) ; and southern Baja California (La Paz). 



Casual in northeastern British Columbia (Lower Liard Crossing) ; 

 southwestern Manitoba (Aweme) ; southwestern North Dakota (Buf- 

 falo Springs Lake) ; eastern South Dakota (Aberdeen) ; Nebraska 

 (Stapleton, North Platte, and Hastings) ; Kansas (Blue Rapids) ; 

 and northwestern Texas (Gainesville). 



The range as outlined is for the entire species, of which two sub- 

 species are recognized. The northern MacGillivray's warbler {Opo- 

 ToiTiis tohniei tolmiei) is found from southern Alaska, British Colum- 

 bia, north-central Alberta, southwestern Saskatchewan, and south- 

 western South Dakota south to southern Baja California, throughout 

 Mexico (except the Yucatan Peninsula), Guatemala, El Salvador, 

 Costa Rica, Panama, and northern Colombia ; the southern MacGilli- 

 vray's warbler {Oporornis tolmiei monticola) is found from north- 

 eastern Calif orni?, southern Oregon, southern Idaho, southern Wyo- 

 ming, northern and central Nevada, central Arizona, and through 

 central Colorado to south-central New Mexico south to Colima, 

 Michoacan, Morelos and Guatemala. 



Migration. — ^Late dates of spring departure are: El Salvador — 

 Volcan de Santa Ana, May 15. Guatemala — above Tecpan, May 10. 

 Tamaulipas — Gomez Farias region. May 3. Sonora — Rancho la Ari- 

 zona, May 22. 



Early dates of spring arrival are : Sonora — Chinobampo, March 7. 

 Texas — El Paso, April 21; Los Fresnos, Cameron County, May 4. 

 Oklahoma — Cheyenne, May 13. Nebraska — North Platte and Hast- 

 ings, May 7. North Dakota — Wilton, May 22. Saskatchewan — Wise- 

 ton and Conquest, May 25. New Mexico — Fort Bayard, April 1. Ari- 

 zona — Tucson, March 23. Colorado — Denver, May 1. Utah — Pine 

 Valley, Washington County, May 11. Wyoming — Torrington, May 7. 

 Idaho — Meridian, May 5. Montana — Fortine, May 11. Alberta — 

 Onoway and Waterton Lakes Park, May 25. California — Berkeley, 

 April 2 (average for 18 years in San Francisco Bay region, April 13) . 

 Nevada — Pioche, May 12. Oregon — Salem, April 17. Washington — 

 Shelton, April 15; Walla Walla, April 28. British Columbia— 

 Courtenay, Vancouver Island, April 14. Alaska — Wrangell, June 9. 



Late dates of fall departure are : Alaska — Point Barrow, September 

 12. British Columbia — Okanagan Landing, October 2. Washing- 

 ton — Kamiak Butte, Wliitman County, September 27. Oregon — Eu- 

 gene area, November 2; Multnomah County, October 12. Nevada — 

 south end of Belted Range, Nye County, September 28. California — 

 San Francisco Bay region, November 27; Los Angeles, October 24. 

 Montana — Fortine, September 11. Idaho — Moscow area, September 



