87 
HERONS, BITTERNS, ETC.: BLUE HERON 
HERONS AND EGRETS: Subfamily Ardeinae 
True Herons have highly developed nuptial plumes and some have 
two color phases—dark and white. Egrets are herons most of which are 
wholly white. The colors of bill, lores, legs, and feet are variable with 
age, season, and even individuals. 
References.—Cooke, W. W., Bull. 45, Biol. Surv., U. S. Dept. Agr., 1913.— 
Pearson, T. G., Bull. 5, Nat. Assoc. Audubon Soc., 1924.— Wetmore, Alexander, 
Condor, XXII, 168-170, 1920 (function of powder downs). 
TREGANZA BLUE HERON: Ardea herodias treganzai Court 
Plate 4 
Description. —Wing 18.5 inches, bill 5.5, tarsus 6.7. Adults in breeding 
plumage: Plead mainly white, with black line over eye and black occipital crest with 
two long filamentous feathers; neck with sides pale brown and median row of black, 
white, and reddish brown feathers; loiver neck with long loose feathers; forepart of 
back silvery bluish gray, shoulder plumes whitish, long and lanceolate; rump bluish, 
tail bluish black; bend of wing bright chestnut and white, quills blackish, axillars 
and wing linings bluish; breast and belly broadly streaked with white; flanks dark 
bluish slate; thighs deep reddish brown; iris yellow; bill blackish above, yellow below; 
feet and lower legs slaty, upper brownish or yellowish. Adults in winter plumage: 
Without crest. Young in Juvenal plumage: Long feathers wanting. 
Range. —Breeds in Transition and Sonoran Zones of the Western United States 
except the Pacific coast region from (Washington and Oregon, probably) Montana, 
Wyoming, and central Colorado south to central-western Texas, southern New 
Mexico (Chihuahua probably), Arizona, Nevada, Sonora, and northern Lower 
California; winters in the southwestern United States and Mexico, from Utah, 
Arizona, New Mexico, and Texas south to west coast of Mexico; north occasionally 
to Idaho and Wyoming. 
State Records. —Among the herons, the Treganza Blue is almost the only one 
that breeds regularly in New Mexico. Its summer range includes favorable localities 
in much of the State at the lower and middle altitudes, since it is known to nest at 
Carlsbad, 3,100 feet (Bailey), F'ort Thorn, 3,S00 feet (Henry), the Gila River, 4,500 
feet (Metcalfe), Chloride, 6,000 feet (Blinn), Rinconada, 6,000 feet (Surber), and 
Ribera, 6,000 feet (Bailey). One was shot July 16, 1904, on Red Willow Creek in 
the Taos Mountains at about 8,000 feet, but it may have nested at a lower altitude. 
About 25 birds were noted July 20, 1913, at Lake Burford, 7,500 feet, most of them 
young birds that had been reared in the trees along the lake shore. [In Crane Canyon 
about 60 miles north of Roswell they have nested for many years, and in 1918 about 
a dozen old nests were found in two trees. In Buffalo Draw about 15 miles north of 
Crane Canyon on June 19, 1918, three nests were found containing young ten days 
old and over; several pairs also nest regularly near the J Ranch on the Gila River, 
north of Silver City. Two were seen, May 7, 1920, at Gray Ranch, Animas Valley 
and three, May 9, at the San Simon marshes. A nesting rookery was visited, May 
14, 1924, at Red Rock, on the Gila River (Ligon).] 
In migration the species ranges much higher, since it was seen August 27, 
1908, at Beaver Lake in the Gila National Forest at about 7,500 feet (Birdseye), 
and was quite common October 6-12, 1908, at the small lakes in the Chuska Moun¬ 
tains among the yellow pines and aspens up to about 9,000 feet (Bailey)- It was 
seen in the northern part of the State near Koehler Junction, one on August 20 and 
