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The most reliable field mark to separate Little Egret from Striated Heron is overall color and structure: Little Egret is entirely white (except for bill, legs, and feet), with a slender, elegant build and long black legs with yellow feet, while Striated Heron is a compact, short-legged heron with a blue-grey back and wings, dark cap, and variable underparts. Juvenile Striated Herons are brownish above and heavily streaked below, never all-white. In flight or at rest, the Egret's white plumage and long neck contrast strongly with the Heron's darker, shorter-necked appearance. Bill color and leg color are also key, especially in adults. Both species can be found in wetland habitats, but Little Egret is larger and more likely to be seen foraging actively in open shallow water, while Striated Heron prefers skulking near cover.

1. All-white plumage: Little Egret of all ages is essentially white, with only rare greyish or brownish tinge in juveniles. Striated Heron is never all-white; adults are blue-grey above, white below, and juveniles are brown and streaky. If the bird is entirely white, it's a Little Egret.
2. Bill color and shape: Little Egret has a long, slender, entirely black bill (with some greenish-grey at base). Striated Heron has a shorter, stouter bill, dark but not as slender, and with a dark line extending under the eye. Bill shape is a strong clue at close range.
3. Leg and foot color: Adult Little Egret has long black legs and bright yellow feet (which may turn red in courtship). Juveniles have greenish-black legs and duller yellow feet. Striated Heron has short yellow legs in adults, never the long-legged look of the Egret. Leg length and color are key in good light.
4. Neck length and posture: Little Egret has a long neck, often held in an S-shape, especially in flight. Striated Heron is short-necked and appears hunched both at rest and in flight.
5. Size and structure: Little Egret is much larger and more elongated, with a longer neck, legs, and wings. Striated Heron is compact, short-legged, and short-necked. If you see both together, the difference is obvious, but even singly, the Egret's elegance stands out.
6. Breeding plumes: In breeding season, Little Egret shows long, wispy nape and scapular plumes. Striated Heron never shows such plumes.
7. Juvenile confusion: Juvenile Little Egret is still mostly white, with only minor greyish or brownish feathers. Juvenile Striated Heron is brown above and heavily streaked below. If you see a streaky, brownish young heron, it's a Striated Heron.
8. Flight appearance: Little Egret in flight is a white bird with black bill and legs, yellow feet trailing behind. Striated Heron in flight is dark above, pale below, with no white wing panels or trailing edges.
9. Habitat and behavior: Little Egret is more likely to be seen in open water, foraging actively, sometimes in groups. Striated Heron prefers dense cover, skulking alone or in pairs, and is less likely to be out in the open.
10. Feeding style: Little Egret often runs, shuffles feet, or feeds alongside other birds. Striated Heron tends to stand still, ambush prey, and rarely joins mixed-species flocks.
11. Feet color in courtship: Only Little Egret's feet can turn red in peak courtship; Striated Heron does not show this feature.
12. Facial pattern: Striated Heron has a dark line from bill to under eye and a black cap, giving a masked look. Little Egret's face is plain white with yellow lores (sometimes red in courtship).
13. Group size: Little Egret may be seen in groups or colonies; Striated Heron is almost always solitary or in pairs.
14. Plumage consistency: Little Egret's white plumage is consistent year-round, except for breeding plumes. Striated Heron's coloration and streaking are age-dependent, but never white.
15. Contextual clues: In the Americas, check for both species in the same area, especially in the Caribbean where both may occur, but always use plumage and structure for confirmation.

Little Egret is significantly larger and more elongated, with a body mass around 532 g [wikidata], length 55–65 cm, and wingspan 88–106 cm [wikipedia]. Striated Heron is much smaller and stockier, at 35–48 cm in length and a wingspan of 52–60 cm, with a mass of 130–250 g [wikipedia]. The Egret's longer legs, neck, and wings are obvious in the field, especially when both species are seen together. Striated Heron appears compact, almost hunched, with short legs and neck.

Juvenile and adult Little Egrets are always predominantly white, with only minor variation (some juveniles may show a tinge of greyish or brownish feathers, but never an overall dark or streaked appearance). In breeding season, adults have long, fine nape plumes and elongated scapulars, but these are absent or reduced in winter and in juveniles. The bill is always black, legs black (greenish-black in juveniles), and feet yellow (duller in juveniles). Striated Heron adults have a blue-grey back and wings, white underparts, and a black cap, with a dark line from bill to under eye. Their legs are short and yellow. Juveniles are brown above and heavily streaked below, never white. In all ages, Striated Heron shows a clear contrast between dark upperparts and lighter underparts, and never acquires the all-white look of Little Egret. In flight, Little Egret is a white bird with black bill and legs, yellow feet; Striated Heron is dark above, with no white wing panels or trailing edges.

Little Egret is active and often conspicuous, foraging in open shallow water, sometimes running or shuffling feet to disturb prey, and may be seen in groups. Striated Heron is more solitary and skulking, often staying close to cover, moving slowly or standing still at the water's edge. The Egret may feed alongside other waders or even livestock, while Striated Heron is more likely to be alone or in pairs. Juvenile Striated Herons may display by stretching necks and pointing bills skyward when threatened.

Both species use wetland habitats, but Little Egret prefers open shallow waters, estuaries, and sometimes even forages on land. Striated Heron is more tied to dense cover along mangroves, riverbanks, or vegetated water edges, and is less likely to be seen in open areas. If you see a small heron in open water, especially in a group, it's more likely a Little Egret; a solitary, skulking bird close to reeds or mangroves is more likely a Striated Heron.