Cattle Egrets in Central Coahuila

Abstract

On 23 February 1974 Sr. Ignacio Urutia shot a Cattle Egret (Bubulcus ibis) in his garden at Ocampo, an isolated village (elev. ca. 1100 m) in the Chihuahuan Desert of central Coahuila, Mexico (27?22'N, 102* 26'W). The bird appeared emaciated, and dissection revealed no fat. Flies were present in the stomach and completely filled the esophagus. The bird was an immature female with a yellow bill and nearly black feet. The ovary measured 7 x 12 mm. This is the first specimen of a Cattle Egret taken in Coahuila. It has been given to the Field Museum of Natural History, Chicago (FMNH #297139). Ocampo is in a basin surrounded by mountains ranging from ca. 780 to 2900 m. Characteristic plants of the region are creosote-bush (Larrea tridentata), lechuguilla (Agave lechuguilla) and prickly-pear cactus (Opuntia spp.). Mesquite (Prosopis sp.), huisache (Acacia farnesiana) and Acacia rigidula occur chiefly around water. Plants commonly cultivated and irrigated include maize, beans, alfalfa, and sorghum. Cattle Egrets were observed in Coahuila during 1974 as follows: on 19 February, Philip Weisheipl saw one bird flying low over our residence adjacent to Sr. Urutia's garden at Ocampo. This may have been the same bird shot four days later, as Cattle Egrets were not seen again in Ocampo for more than two months. Craig Cady and I saw 27 of these herons about 24 km NE Torre6n on 28 March. John L. Kaspar saw three near Monclova on 10 April. On 25 April, Sylvia Brey saw an immature egret with cattle just southeast of Ocampo. She and Cady observed one in the same plumage at the same site two days later. Brey found three egrets there on her last visit on 28 April. I elieve these sight records to be the first from the ce tr l part of Coahuila. Zimmerman (Condor 75:480-481, 1973) reported sight records of the species from Durango, San Luis Potosi, central Chihuahua, southern Nuevo Le6n and the Torre6n region of Coahuila. Contreras (Publ. Biol. Inst. Invest. Cient. Univ. Auton. Nuevo Le6n 1:2-3, 1973) reported a Cat le Egret collected on 5 December 1971 near the village of China in Nuevo Le6n. I thank John L. Kaspar for his assistance in organizing the manuscript.