It is the largest North American heron herons and among all existing, surpassed only by the Goliath heron and
white-bellied heron. Head-to-tail length of 91-137 cm (36-54 inches),
with a magnitude of 167-201 cm (66-79 inches), a height of 115-138 cm
(45-54 inches) and a weight 2, 1 to 3.6 kg (4.6 to 7.9 pounds). Notable
features include slate flight feathers, red-brown, red-brown thighs, and
a band of black couple and sides, the neck is rusty gray, with black
and white stripes on the front, the head is almost white pale face, and a
pair of black feathers vary from just above the eye to the back of the
head.
Great Blue Heron Credit
Immature birds are duller in color, with a dull blackish-gray
crown, and the pattern of side weakly defined, without feathers, and the
bill is dull gray-yellow. Heron step is about 22 cm (9 inches), almost straight.
The subspecies differ only slightly in size and plumage tone, with the
exception of subspecies occidentalis, which as normal colored birds,
also has a separate white phase, known as the Grand White Heron (not to
be confused with the Great Egret, for "Great White Heron" was
once a common name).
Intermediate between Birds normal and white morph morph are known as Heron Wurdemann, these birds look like a blue "normal" Excellent bald. The Great Blue Heron is found throughout most of North America, as far north as Alaska and the southern provinces of Canada. The range extends south through Florida, Mexico and the Caribbean South America. Birds east of the Rocky Mountains in the northern part of their range are migratory and winter in northern Central America and South America.
The size of these colonies can be large, between 5-500 nests per colony, with an average of approximately 160 nests per colony. Great Blue Herons build a bulky stick nest, and the female lays 3-6 eggs blue. Repeated human intrusion into nesting areas often results in nest failure, with abandonment of eggs or chicks. Both parents feed the young in the nest by regurgitating food. Predators of eggs and chicks are vultures, hawks and crows, raccoons, bears different, the latter two also potential predators of adults.