Little Blue Heron - Egretta caerulea

Little Blue Heron

Egretta caerulea

Order : Ciconiiformes

Family : Ardeidae ;

Biometrics :

Size : 58 à 63 cm
Wingspan : 95 à 105 cm
Weight : 396 gr

Longevity : 14 years

IUCN conservation status :

Extinct

Threatened

Least
concern

Extinc
in the Wild

Near
threatened

Not
evaluated

EX EW CR EN VU NT LC NE

Geographic range :

Synonyms : Garceta Azul (es), Airone azzurro minore (it), Blaureiher (al), Kleine blauwe reiger (nl), Little Blue Heron (en)

Physical description :
Both sexes look similar, but young look different from adults.
Little blue heron is a small and dark bird. It can be recognized by purple brown head and neck. Rest of the plumage is slate grey. It holds its long neck in an S shaped curve when it's at rest or in flight. The long, slender bill curves slightly downward. It's dark grey with black tip. Eyes are yellow. Legs and feet are dark.
The young has all white body plumage. It has a blue bill with black tip. Legs are dull green. It stays white through its first summer, fall, and into winter. It starts moulting in February into the dark colour of an adult.

Voice : Little blue heron is rather silent, but when flushes, gives a harsh, croaking 'gerr'. Its sounds during fighting are much different and resemble the screams of parrots.

Habitat : In natural range, little blue heron prefers freshwater areas such as ponds, lakes, marshes, swamps and lagoons, and sometimes dry grasslands or marine coastlines.
GEOGRAPHIC RANGE: along Atlantic coast from Massachusetts to Florida, and along the Gulf of Mexico. It nests in the West Indies and along both Mexican coasts, through Central America, and into South America. Its range can extend into the Amazon Basin, Caribbean, and the more northern regions of North America.

Behaviour : Little blue heron is not an energetic bird. Sometimes, it walks quickly, or even runs, but usually, it's walking slowly and daintily along marshes. It's a solitary bird while hunting, but it nests with others in small or large colonies.
During the courtship display, the male stretches its neck upward, with the bill pointing up, and assuming a crouched posture. Its movements include bill snapping, vocalizing and neck swaying. If the female is impressed, she will approach it. First encounter can be very aggressive but, after a while, we can see signs of affection such as feathers nibbling and neck crossing. The male takes sticks to present to the female, raising its feathers and nibbling feather's female, as she places the sticks into a nest structure.
Little blue heron feeds during the day. It's carnivorous. Its long legs enable it to wade into the water where it walks slowly to locate prey, often retracing its steps or standing motionless. It rakes the ground with its foot to disturb prey, and stretches its neck to peer into the water. It takes the prey with its long bill and eats this prey.

Flight : Little blue heron has a graceful but strong flight. It flies with its head down, and legs extended to the rear.

Reproduction-nesting : Little blue heron's nest is usually built up to 3 to 4/5 metres above the ground or water, but can be as high as 12 metres (about 40 feet).
Female lays 3 to 5 eggs, pale blue green eggs, in April. The process takes some days, with one egg per day. Incubation lasts about 22 to 24 days, by both parents. They quickly remove the eggshells from the nest. It may take about 5 days to hatch. The young can raise their heads, but they spend most of their time lying on the nest floor. Both parents feed them by dropping food into the nest, and later, placing it into the young's mouths.
The chicks leave the nest in about 3 weeks, doing short trips around the nest. When they are 30 days old, they can fly out the nest area. They become independents at about 42 to 49 days, and they can breed when they are one year old.

Food habits : Little blue heron diet consists of fish, frogs, lizards, snakes, turtles and crustaceans, such as crabs, crayfish and shrimp. It also eats aquatic insects and spiders. When wet areas become dry, it lives on grasshoppers, crickets, beetles, and other grassland insects.

Protection / threats : Little blue heron is loosing its wetlands habitat. Colonies are being lost because of clear cutting of forests, and draining of ponds, lakes and wetlands. Pesticides cause eggshells thinning. Populations are decreasing and this species is considered threatened.

Other links :
Iucn
Birdlife

Specification sheet created by Nicole Bouglouan

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Updated on 2008/05/04 05:30:55 - © 1996-2008 Oiseaux.net