Great Blue Herons are the largest and most widespread herons in North America, and they are a common and majestic sight across virtually all wetland habitats in Oregon. Despite their prominence, telling male and female Great Blue Herons apart in the field is extremely difficult, as they exhibit virtually no visual sexual dimorphism.

General Appearance (Adults, Both Sexes):
Size and Shape: Great Blue Herons are impressively large, standing 3 to 4.5 feet (0.9 to 1.4 meters) tall with a wingspan ranging from 5.5 to 6.5 feet (1.7 to 2 meters). They have a long, S-curved neck, long, sturdy legs, and a powerful, dagger-like bill.
Plumage:
Body: Their overall body plumage is a soft, bluish-gray.
Head: They have a distinctive head pattern: a white face with a prominent **black stripe** that starts above the eye and extends back to form two long, ornamental **black plumes** that stream from the back of the head.
Neck: The neck is typically a pale rusty or cinnamon color, often with some dark streaking on the front.
Underparts: The belly usually has some streaking, often with rusty or darker patches.
Shoulders/Wings: The shoulders and part of the wings have a reddish-brown or rusty patch.
Bill Their bill is long, strong, and yellowish, often with a darker gray or dusky upper mandible, especially towards the tip. During the breeding season, the bill may become brighter orange-yellow.
Legs and Feet: Their legs and feet are dull greenish-gray or blackish. During the breeding season, particularly around nest sites, their legs and feet can temporarily become a brighter, more reddish-orange.

Sexual Dimorphism (Virtually None Visually):
Size: While statistically, males may average slightly larger and heavier than females, this difference is almost impossible to discern with the naked eye in the field. There is significant overlap in individual sizes, and any perceived size difference is more likely due to individual variation or the angle of observation rather than sex.
Plumage: There are no consistent differences in plumage coloration, patterns, or the length of head plumes between males and females. Both sexes have the same blue-gray body, white face, black eye stripe, and head plumes.
Bill and Leg Coloration: The brightening of the bill and leg color during the breeding season occurs in both sexes.
Vocalization: Both sexes produce a variety of harsh, guttural croaks ("fraaaank" or "kraak"), especially when disturbed or flying. During courtship and at the nest, they have a wider range of calls, but these are not sex-specific identifiers.
Behavior: Both males and females participate equally in nest building, incubation, and raising the young.

Juvenile Great Blue Herons:
Juveniles look noticeably different from adults. They generally have a dull, darker gray crown without the distinct white face and black plumes of adults. Their overall plumage is often duller and browner, with less distinct streaking and more mottled appearance. Their legs and bill are typically duller, too. They gradually acquire adult plumage over their first two years.

Habitat and Behavior in Oregon:
Great Blue Herons are highly adaptable and can be found in almost any aquatic habitat across Oregon, including lakes, rivers, and ponds, marshes and wetlands (freshwater and brackish),
coastal estuaries, mudflats, and rocky shores, flooded agricultural fields.

They are primarily solitary foragers, hunting by standing motionless in shallow water or slowly stalking prey. Their diet is diverse but mainly consists of fish, amphibians (frogs, salamanders), reptiles (snakes), large insects, and small mammals (voles, shrews). They often forage by day but can also be active at night.