Grey Heron - Ardea cinerea

Grey Heron

Ardea cinerea

Order : Ciconiiformes

Family : Ardeidae ;

Biometrics :

Size : 90 à 98 cm
Wingspan : 175 à 195 cm
Weight : 600 à 1200 g

Longevity : 25 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 : Seraya Tsaplya (ru), Grå häger (sv), Garza real (es), Airone cenerino (it), Graureiher (al), Blauwe Reiger (nl), Grey Heron (en)

Physical description :
Grey Heron is a large majestic grey bird when standing up at rest. It has long greyish or grey legs, long neck, and large greyish-yellow dagger-shaped bill. Underparts, head and neck are whitish with black crest and dark streaks on fore neck and breast. Rest of plumage is slate-grey. When flying, sometimes high with slow wing beats, we can see its arched wings, the dark, almost black flight feathers, the tucked up neck and the legs longer than tail.
Both sexes are similar.
Young heron has grey forehead and crown, greyish nape with shorter crest than adults. It has grey sides of neck and head, and also grey back. Centre of the neck is beige.
They search for food near all kinds of waters, and they may be found sometimes in urban areas. At this time, they have to learn how to fish for feeding!

Voice :
Sound from CD 'Tous les Oiseaux d'Europe' by Jean C. Roché by courtesy of Sittelle and CEBA. Typical call in flight, often uttered at dusk, is raucous, loud and croaking. Colony is very noisy and numerous pecks can be given.
Grey Heron's voice is relatively unpleasant. It is a hard and high-pitched croaking 'fraark' given in flight. This same call may be heard at nest, by day or night, with other guttural sounds 'frauk-jauk-jauk-ak-ak'. We can also hear a very ringing croaking 'kraoj'.

Habitat : Grey Herons frequent any kind of wet area (marsh, streams, ponds...) where they can find food. It could be freshwater, brackish or salt water, slow or rapid current, but shallow water. They also frequent forests close to the water.
GEOGRAPHIC RANGE: Grey Heron is relatively common resident and widespread in most part of Europe. We can observe northern bird's migration southwards during hard winters.

Behaviour : Grey Heron may have some strange attitudes. It is able to stay motionless during hours, perched on one leg, if not disturbed. Its neck is sunk between shoulders, with only horizontal head and bill rising from its body. If alarmed, it stretches its neck, motionless and watchful, and may take off immediately.
It hunts by particular manner. It walks slowly and bowed, in shallow waters, noiseless, down-targeting its strong and pointed bill, ready to kill the prey crossing by it.
Sometimes, it stays motionless in the water, watching ahead or on the sides, in order to capture easily any fish crossing by it.
For large preys, (large fish or big eel), it strikes them strongly with its bill to stab them, and shakes them side to side before to swallow the whole prey head first.
When in flocks, Grey Herons walk on line, mainly at dusk, gleaning here and there. At this time, particularly in autumn, they search for insects, but also small rodents and frogs.
Grey Heron's courtship display is an elaborated ceremonial. Heron arriving at nest erects its crest, while it utters a loud, hard call. The one occupying the nest answers with stretching neck upwards, and moving it back and forth, with bill pointed upwards and crouching, in order to have its body at the nest level. Then, it bends the neck, with the head at legs' level, and snaps noisily the bill. Actually, this ceremonial is a call to the male with insistent manner from the old nest, using the same movement and taking frequently a twig into the bill.
If a female approaches and enter strongly into the nest site, she may be immediately evicted from the nest by the male. Females have to adopt a shy and gentle attitude to win the male's trust. When one is accepted, male snaps the bill from 20 to 40 times. Pair lacks only one breeding season.

Flight : Grey Heron performs a slow flight with deep wing beats, giving a powerful impression. It takes off in majestic manner. It sometimes glides, rather before landing.

Reproduction-nesting : Grey Heron builds a very large nest with dry twigs, branches and sedges. Materials vary according to the habitat. The interior of this large structure is a cup fashioned with twigs, cattails and grass. This nest may serve year after year.
Grey Heron nests in large colonies, with numerous nests on one tree. Male brings materials and female remains at nest almost the day long, assuming the construction weaving branches and sedges. When the male comes back to the nest, we can see the courtship display's ceremonial, including during incubation period.
Female lays 3 to 5 dull grey-blue eggs, sometimes with some reddish tint. Eggs are laid each two days. Incubation lasts about 26 days, shared by both parents.
When they hatch, chicks have comic appearance, with dense down on head, as a large crest.
They are fed by both adults. Parents care their young attentively. During the first 20 days, an adult remains at nest to keep an eye on the young. Male and female incubate by turns four times a day, always with the same display. Young are protected from sun and rain. Chicks give some small knocks to parents' bills, and adults regurgitate food directly into their mouths.
Young are able to fly at about 55 days old.
Grey Heron produces only one brood per year, rarely two, except if the first clutch is destroyed. In this case, another clutch comes quickly after destruction of previous brood.

Food habits : Grey Heron feeds mainly on fish, eels and batrachians. It also may consume small rodents, insects, crustaceans and reptiles. It hunts on the watch, perfectly motionless. With great speed, it tenses its neck and its dagger-shaped bill jabs the prey.

Protection / threats : Grey Heron is vulnerable to hard winters with frozen waters, and northern populations have an important mortality during these cold periods. However, this species shows a good recovery in following years.
Grey Herons are killed by hunting and trapping. Habitat loss in some parts of its range, with cutting down trees and human disturbances, may compromise nesting.
At this time, this species is not endangered, thank to its entire protection, and better habitat management.

Other links :
Iucn
Birdlife

Specification sheet created by Nicole Bouglouan

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