Birds from Coahuila, Mexico

by Emil K. Urban

*Corvus corax sinuatus Wagler.—The Common Raven seems to occur in low density in Coahuila. Miller (1955a:168) saw ravens in the pine-oak and cliff areas of the Sierra del Carmen, and took a breeding female at the head of Corte Madera Canyon, 7500 feet. Burleigh and Lowery (1942:196) found this species to be a bird of the higher slopes of the mountains although not uncommon in the broad open valley south of Diamante Pass. Sutton and Burleigh (1939a:35) took a male at Santa Rosa.

*Corvus cryptoleucus Couch.—Specimens examined: total 4: ♂ 32080 from 2 mi. W Jiménez, 850 ft., June 20, 1952; ♀ 35404 (skeleton only) from 4 mi. N San Isidro (=16 mi. N Ocampo), May 10, 1954; and ♂ ♂ 31474-31475 from R. de Almendárez (=53 mi. NW Ocampo), May 11, 1954.

The White-necked Raven occurs throughout Coahuila. Sutton and Burleigh (1939a:36) observed this species "in the vicinity of Saltillo," but not farther west. Burleigh and Lowery (1942:197) noted C. cryptoleucus frequently "on the arid plateau around Saltillo" and obtained a specimen "in the high fertile valley south of Diamante Pass." Burleigh and Lowery (loc. cit.) remarked that the White-necked Raven avoids the mountain slopes; 7000 feet was the uppermost limit of occurrence. The sizes of the testes (32080, 20 mm.; 31474: left, 12×20 mm., right, 10x16 mm.; and 31475: left, 10×16 mm., right, 10×14 mm.) of the specimens that I have examined and the dates (May 11, June 20) on which they were collected indicate breeding by the White-necked Raven in Coahuila.

*Parus sclateri eidos (Peters).—Specimens examined: total 4: ♀ 32083 from 7 mi. S, 4 mi. E Bella Unión, 7200 ft., June 25, 1952; ♂ 31609 from 2 mi. E Mesa de Tablas, 9000 ft., January 15, 1954; ♂ 31656 and ♀ 31655 from the north slope of Sierra Guadalupe (=11 mi. S, 7 mi. W General Cepeda), 7800 ft., April 20, 1953.

The Mexican Chickadee is common in southeastern Coahuila. Miller, Friedmann, Griscom, and Moore (1957:133) stated that P. s. eidos and P. s. sclateri intergrade in southern Coahuila. The specimens that I have examined also show signs of intergradation, but are closer to P. s. eidos.

Sutton and Burleigh (1939a:36) reported taking specimens of P. s. eidos at Diamante Pass where they saw several individuals. Burleigh and Lowery (1942:197) also observed these chickadees "in the pine woods about the summit of Diamante Pass...." The size of the testes (6×5 mm.) of No. 31656 and the fact that No. 31655 was incubating eggs at the time it was obtained are evidence of breeding by this chickadee in the State.

**Parus sclateri sclateri Kleinschmidt.—Miller, Friedmann, Griscom, and Moore (1957:133) stated that a specimen (or specimens?) of P. s. sclateri which showed evidence of intergradation with P. s. eidos was obtained at El Diamante.

**Parus atricristatus dysleptus Van Tyne.—Specimen examined: one, ♂ 31054 from 37 mi. S, 21 mi. E Boquillas, 4100 ft., March 13, 1952.

Two subspecies of the Black-crested Titmouse are present in Coahuila. P. a. dysleptus occurs in northwestern Coahuila. Miller (1955a:168) stated that the Black-crested Titmouse, identified as dysleptus, was the only representative of the genus Parus in the Sierra del Carmen. The weak extension of black onto the nape in No. 31054 suggests intergradation between P. a. dysleptus and P. a. atricristatus; the latter lacks the black nape of dysleptus.

*Parus atricristatus atricristatus Cassin.—Specimens examined: total 4: ♀ 32084 from 12 mi. N, 12 mi. W Jiménez, 850 ft., June 19, 1952; sex ? 32085 from 2 mi. W Jiménez, 850 ft., June 20, 1952; ♀ 31055 (skeleton only) from Fortín (=33 mi. N, 1 mi. E San Gerónimo), 3300 ft., on March 29, 1952; and ♀ 35399 (skeleton only) from 3.5 mi. W, 22 mi. S Ocampo, December 15, 1953, weight, 16 gms.