Birds from Coahuila, Mexico

by Emil K. Urban

**Progne chalybea chalybea (Gmelin).—The only record of the Gray-breasted Martin in Coahuila was given by Ridgway (1904:42) when he listed P. c. chalybea from Sabinas.

**Cyanocitta stelleri macrolopha Baird.—Specimens examined: total 2: ♂ 32788 and ♀ 32787 from 13 mi. E San Antonio de las Alazanas, 9950 ft., July 6, 1955.

From the paucity of records in the literature, I judge that Steller's Jay is uncommon in Coahuila. Nos. 32787-32788 seemingly represent the first records of this species in the State, and are referred to the subspecies macrolopha on the basis of relatively long (150, 151 mm.) wing, near the maximum for stelleri from México. The date (July 6) of collection suggests that these birds were resident in southeastern Coahuila.

**Aphelocoma coerulescens cyanotis Ridgway.—The Scrub Jay is common in southeastern Coahuila. Burleigh and Lowery (1942:196) noted this species in small numbers at the summit of Diamante Pass, daily on the lower slopes of the mountains, and a few birds "on the outskirts of Saltillo, where they were probably nesting...." Sutton and Burleigh (1939a:35) also noted several flocks at Diamante Pass. Miller, Friedmann, Griscom, and Moore (1957:123) reported A. c. cyanotis from El Diamante. Ridgway (1904:335) listed this subspecies of the Scrub Jay (then called Aphelocoma cyanotis) from Carneros, Sierra Encarnación, and Sierra Guadalupe.

*Aphelocoma ultramarina couchii (Baird).—Specimens examined: total 14: ♀ 31051 from Sierra de la Encantada (=38 mi. S, 23 mi. E Boquillas), 4400 ft., March 15, 1952; ♂ ♂ 29425-29426 and ♀ ♀ 29427-29428 from Club Sierra del Carmen (=2 mi. N, 6 mi. W Piedra Blanca), 4950 ft., April 8, 1950; sex ? 31052 (skeleton only) from 4 mi. W Hacienda La Mariposa, 2300 ft., March 25, 1952; ♀ ♀ 31635-31636 from Canyon de Parazos in the Sierra de la Parazos Azula (=9 mi. E Hermanas), 2100 ft., December 7, 1953; ♀ 32082 from 4 mi. N, 21 mi. W Cuatro Ciénegas, 6200 ft., July 3, 1952; ♀ 31053 (skeleton only) from 26 mi. W Santa Teresa, 7050 ft., April 5, 1952; ♂ 32081 from 7 mi. S, 4 mi. E Bella Unión, 7200 ft., June 25, 1952; ♀ 33173 (skeleton only) from 13 mi. E San Antonio de las Alazanas, 9950 ft., July 6, 1955; ♂ 31607 from 13 mi. E, 3 mi. S San Antonio de las Alazanas, 8900 ft., January 11, 1954; and ♂ 31654 from Sierra Guadalupe (=10 mi. S, 5 mi. W General Cepeda), 7000 ft., April 13, 1953.

The Mexican Jay is common in Coahuila. This species occupies various habitats in the State and has been collected at stations ranging from 2100 to 9950 feet.

Miller (1955a:167) stated that the Mexican Jay was the most abundant species of bird in the Sierra del Carmen. Burleigh and Lowery (1942:196) remarked that specimens of A. u. couchii were obtained "in the area surrounding the summit of Diamante Pass." At no time did Burleigh and Lowery (loc. cit.) see this species below 6500 feet. The Mexican Jay is restricted to the higher altitudes in southern Coahuila but is more widespread in northern Coahuila. Dickerman saw Mexican Jays in the Sierra del Pino on May 12, 1954; 16 mi. E and 18 mi. N Ocampo on May 7, 1954; in the Sierra de la Madera on December 13, 1953; and 20 mi. S Ocampo on April 4, 1954.

Ridgway (1904:340) remarked that Aphelocoma sieberii potosina Nelson [=A. u. couchii (Baird)] has been recorded in southern Coahuila, at Carneros. Miller, Friedmann, Griscom, and Moore (1957:124) recorded A. u. couchii from Carneros, Nuevo León. I suspect (Ridgway, 1904:340 and Goldman, 1951: map opposite p. 34) that the locality given by Miller, Friedmann, Griscom, and Moore (op. cit.) should be Carneros, Coahuila, rather than Carneros, Nuevo León.

Specimens (31051, 29425-29428, 31635-31636, 32081-32082, 31607, and 31654) of the Mexican Jay increase in size from northern Coahuila to southern Coahuila. The average length of the wings of Nos. 29425-29426 from Club Sierra del Carmen is 152 mm. whereas the average length of the wings of No. 32081 from 7 mi. S and 4 mi. E Bella Unión, of No. 31607 from 13 mi. E and 3 mi. S San Antonio de las Alazanas, and of No. 31654 from Sierra Guadalupe is 164 mm.

Miller (1955a:169) indicated that the Mexican Jay breeds in the Sierra del Carmen. Burleigh and Lowery (1942:196) remarked that the species breeds at Diamante Pass. The sizes of the testes (12, 11 mm.) of Nos. 29425-29426, the size of the ovum (8 mm.) of No. 29428, and the short tail (126 mm.) of the immature female from 4 mi. N and 21 mi. W Cuatro Ciénegas are also evidence of breeding by this species in the State.