The little blue heron (Egretta caerulea) is a small heron that resembles the more common great blue heron. It is smaller in size, with all-dark plumage in juveniles and a mix of white and blue/purple plumage in adults. The little blue heron can be found along the coasts, wetlands, and waterways of North America. Its striking appearance and some unique behaviors make it a bird worth learning about for birders and nature enthusiasts.
What does a little blue heron look like?
The little blue heron goes through dramatic changes in appearance from juvenile to adult. This can make identification tricky at times.
Juvenile Plumage
Juvenile little blue herons have entirely slate-gray plumage. Their bills are two-toned, with a black tip and pale base. Their legs are yellowish-green. They may be mistaken for immature black-crowned night herons at this stage, but can be distinguished by their all-dark gray coloration (night herons have white mottling on the wings).
Adult Plumage
Adult little blue herons develop striking blue-and-white plumage. The body is mainly slate-blue, with a maroon-brown neck and white stripe up the front. The crown becomes black. The bill turns solid yellow. The legs remain yellow-green. In flight, the feathers of the wings are blue on top and slate-gray below.
Adult little blue herons closely resemble snowy egrets in plumage. They can be distinguished by their blue-and-maroon neck versus the snowy’s all-yellow bill and black legs. Great blue herons are much larger with a heavier yellow bill.
Size
The little blue heron measures 19-22 inches in length with a wingspan around 32 inches. It weighs only around 1 pound. This makes it noticeably smaller than the great blue heron, which is around 46 inches long with a 6 foot wingspan.
Where do little blue herons live?
The little blue heron has a range concentrated in the southern and eastern United States, Central America, and the Caribbean islands. Its breeding range extends from the Mid-Atlantic coast south to Florida and west to Texas. Some breeding may occur as far north as Massachusetts.
During the winter, northern populations of little blue herons migrate south to warmer climates. They can be found wintering along the Gulf Coast, throughout peninsular Florida, in Central America, and in the West Indies.
Within their range, little blue herons inhabit freshwater and saltwater wetlands. This includes marshes, swamps, ponds, flooded fields, mangrove forests, and shorelines. They nest in trees or shrubs near foraging sites.
What does a little blue heron eat?
The diet of the little blue heron consists mainly of small fish, amphibians, and crustaceans. They stalk slowly through shallow wetlands searching for prey. Common food sources include:
– Small fish like minnows, killifish, and sunfish
– Frogs, salamanders, tadpoles
– Crayfish, crabs, shrimp
– Aquatic insects
– Small rodents, lizards, snakes
Little blue herons hunt by standing motionless in shallow water and waiting for prey to come near. They then strike rapidly with their bills. Sometimes they shuffle their feet to stir up hiding prey. They also ply the shorelines looking for food.
How do little blue herons breed and nest?
The breeding season for little blue herons runs from March to May. They nest in colonies, often with other wading bird species. The male selects a nesting site in trees or shrubs near water, typically 3-15 feet above ground.
The female lays 3-5 pale blue eggs. Both parents share incubation duties, which lasts around 20-25 days. The chicks hatch helpless. They are fed by regurgitation and fledge in about a month.
Interestingly, adult little blue herons develop white breeding plumage only after their first year when reaching sexual maturity. Younger birds in gray juvenile plumage do not breed.
What is unique about little blue heron behavior?
Some interesting facts about the behavior of little blue herons:
Foraging Strategy
Little blue herons sometimes use bait to hunt. They drop objects like twigs, insects, or flower petals onto the water’s surface to attract curious fish.
Flying Capability
Despite their small size, little blue herons are strong fliers capable of long distance migration. Some travel over 1,800 miles between breeding and wintering grounds.
Color Change
Their progressive white plumage develops through a two-year molting process. The color comes from hollow air sacs in the feathers, causing them to appear blue.
Social Behavior
They are social and nest in large colonies. Dozens may nest in a single tree. But they forage solitarily once breeding finishes.
Wariness
Little blue herons are more secretive and wary than great blue herons. They usually flush from nests or perches at much greater distances when approached.
Is the little blue heron population threatened?
The little blue heron has a large population estimated between 150,000 to 200,000 individuals. Their numbers appear to be stable, so the species is not considered threatened or endangered.
However, the Audubon Society lists it as a species of conservation concern due to isolated declines in parts of its breeding range. For example, numbers in southern Florida have diminished due to habitat loss and disturbance to nesting colonies.
Overall the outlook is positive for little blue herons, but continued protection of wetlands will be important for this wetland specialist.
Where can I see a little blue heron?
Your best chance of sighting a little blue heron is in its southern breeding range from March to August. Some good places include:
Southeastern Coastal Areas
– Florida Everglades
– Coastal marshes of Georgia and the Carolinas
– Bald Head Island, North Carolina
– Blackwater National Wildlife Refuge in Maryland
Gulf Coast
– Laguna Atascosa National Wildlife Refuge in Texas
– Audubon sanctuaries near New Orleans
– Dauphin Island, Alabama
Central America
– Mangrove forests in Belize
– Caño Palma Biological Station in Costa Rica
– Cienaga Grande de Santa Marta in Colombia
Look for them slowly stalking in shallows or roosting solitarily in trees. A good pair of binoculars will help spot their distinctive plumage.
Conclusion
The little blue heron is a delight to observe with its graceful beauty, interesting behaviors, and dramatic changes from juvenile to adult. Although small, it is a strong flier capable of long migrations. Look for these “mini” blue herons around wetland habitats in the southeastern U.S. and Central America. Protecting waterways from pollution and development will help ensure stable populations.