The blue heron is a large wading bird found throughout much of North America. Adult blue herons have a slate-gray body, a whitish head with a black stripe through the eye, and a yellow bill. Juvenile blue herons look quite different from the adults. Their plumage is mostly brown and white during their first year of life. By understanding what a juvenile blue heron looks like, bird watchers can more easily identify these young birds in the wild.
Identifying Features
During their first year of life, juvenile blue herons have a mix of white and cinnamon-brown feathers. Their heads and necks appear light brown on the top and whitish on the bottom. The crown of their head is brown. They have a distinctive white stripe above their eye that contrasts with their darker facial coloring. Their bill is two-toned, with a black upper mandible and yellowish lower mandible. The juvenile’s legs are yellowish-green.
As they mature, juvenile blue herons gradually acquire more slate-gray adult feathers starting around 6 months old. At this stage, their neck may appear mottled with gray and brown. By one year of age, most of their body has transitioned to an adult-like gray, but some brown feathers may still persist on their wings, chest or head. The bill becomes uniformly yellow. By two years old, juveniles are almost indistinguishable from adults.
Size
Juvenile blue herons are nearly as large as adults, though on the lower end of the size range. They measure 36-49 inches tall with a wingspan around 60 inches. They weigh only slightly less than adults at around 2-3.5 pounds. This makes them one of the larger heron species found in North America. Their large size aids identification.
Behavior
The behavior of juvenile blue herons is similar to adults. They usually forage alone rather than in groups. Their diet consists mainly of small fish, amphibians, reptiles, and invertebrates. Juveniles often hunt in shallow water along shorelines and wetlands.
Like adults, juveniles employ a patient hunting strategy. They will stand motionless or walk slowly through the water with an s-shaped neck. When prey is spotted, they quickly jab with their bill. Juveniles may flutter their wings or take larger prey back to shore after spearing it.
Juvenile and adult blue herons often nest together in colonies called heronries. But juveniles are dependent on their parents for feeding and protection at first. As they gain independence, juvenile blue herons disperse further from the nest site.
Range
The blue heron has an extensive range across North America. They are found year-round throughout the lower 48 United States, southern Canada, and south to Central America.
Juvenile blue herons occupy the same range. But juveniles living in northern areas are more migratory. Some northern juveniles migrate south for their first winter. By adulthood, they may take up year-round residence like other populations.
Within their widespread range, juvenile blue herons frequent the same wetland habitats as adults. Look for them along shorelines, marshes, streams, ponds, and flooded fields.
Plumage Variations
Two subspecies of the blue heron exist in North America – the great blue heron (A. h. herodias) and the slightly smaller western great blue heron (A. h. fannini). Intermediate size birds occur where their ranges overlap.
The plumage of juveniles in both subspecies is very similar. But the western birds average a bit more cinnamon coloring on the head and neck compared to the paler great blue herons. Western juveniles also tend to have darker bills. Where both subspecies occur, these subtle differences may aid identification.
Rare dark-colored color morphs do sometimes occur among juvenile blue herons. These individuals appear much darker gray rather than white on the underside. Very rarely, albino juveniles may be observed.
Difference from Immature Little Blue Heron
The plumage of juvenile blue herons bears some resemblance to the immature little blue heron. However, little blue herons are noticeably smaller with a more slender build. Little blue herons have yellowish-green legs rather than grayish-green legs like juvenile blue herons. The small patch of white on the cheek and throat is also diagnostic for little blue herons.
When seen together, the size difference helps distinguish between juvenile blue herons and immature little blue herons. Plumage and structural differences become more apparent with good viewing conditions.
Difference from Immature Night Herons
Two species of night heron – black-crowned and yellow-crowned – may also be mistaken for juvenile blue herons. However, night herons are stockier with thicker bills. Black-crowned night herons have pale gray bills as juveniles rather than two-toned bills. Yellow-crowned night herons have uniformly black bills. The white markings differ, with night herons having bold white spots compared to the blue heron’s streaks. Night herons are also more active foragers, walking quickly rather than standing still.
The habitat preferences of night herons and blue herons may overlap in wetlands, but night herons are more likely to be found around trees. Comparing the overall structure and plumage should prevent confusion.
When and Where to See Juvenile Blue Herons
The best opportunities to spot juvenile blue herons are during late summer and fall. Adults breed between March and June, so juveniles emerge from the nest around July.
Productive areas to find juveniles include:
– Near known heron nesting colonies, where newly independent juveniles remain nearby through fall.
– Shallow wetlands, where juveniles learn to forage on their own.
– Coastal areas, where juveniles feed at low tide.
– Migratory stopover points, for northern juveniles moving south.
– Drying marshes and mudflats, where fish and amphibian prey get concentrated.
As juveniles disperse more widely through their first year, they appear in a broader variety of aquatic habitats. Still, wetlands rich in fish and amphibians remain their preferred foraging grounds.
Patience is needed to observe juvenile blue herons, since they often remain hidden and motionless for long periods. But their large size makes them easily detectable when they move or fly between spots.
Conclusion
Juvenile blue herons can be identified by their distinctive mix of white, cinnamon and dark brown plumage. By one year of age, they closely resemble gray adults but may still show some darker wing or body feathers. Juveniles behave much like adults but depend more on shallow, fish-filled wetlands while learning to forage. Their large size, patient hunting style, two-toned bill and yellowish-green legs help distinguish them from other juvenile herons. With a bit of observational practice, the juvenile plumage of blue herons becomes a familiar sight from mid-summer through fall across much of North America’s wetland habitats.