Great blue heron
The great blue heron is the largest heron species in North America, standing over four feet tall with a wingspan that can exceed seven feet. This elegant bird boasts gray-blue plumage, a mostly white neck with distinctive black streaks, and reddish hues on its thighs. Known for its hunting prowess, the great blue heron employs various techniques to capture a wide range of prey, including fish, amphibians, reptiles, and insects. It is typically found in coastal areas, marshes, and lakes, where it either stands still to ambush prey or stalks quietly through the water.
Breeding behavior is complex, with males performing elaborate courtship dances and displays to attract females. Nesting occurs in trees, with females laying two to seven blue eggs that hatch after an incubation period of about 26 to 30 days. While the survival rate of chicks can be low due to predation and environmental factors, those that reach adulthood have a lifespan of 15 to 25 years. The great blue heron is not considered a threatened species, and it can be found living solitarily or in small groups, making it a fascinating subject of study for bird enthusiasts and nature observers.
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Great blue heron
The great blue heron is the largest heron in North America. It may be over four feet (one meter) tall and have a wingspan of up to seven feet (a little over two meters). This large, long-legged bird is graceful in the air and skillful in hunting.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelecaniformes
Family: Ardeidae
Genus: Ardea
Species: Herodias
The adult great blue heron stands between three and four feet (about one meter) tall and weighs up to eight pounds (3 1/2 kilograms). Gray-blue plumage covers most of the body, while the thighs have a slight reddish hue to them. The heron's neck is mostly white but has black streaks in the front and the same reddish tinge that the bird's thighs do. A black streak runs above each eye. A juvenile bird has dull, red-gray plumage with a black patch on the top of its head and bill.
With its long legs trailing and neck curved in an s-shape, the graceful great blue heron lands in the shallow water. It folds its six-to-seven-foot wings to its side and begins searching for prey. It may feed in the coastal surf at night, but more often hunts during the day in marshes, swamps, rivers, and lakes. The heron may either stand still and wait patiently for prey to approach, or it may walk stealthily and quietly as it stares into the water. Other hunting techniques are to hover over the water and dive or jump upon its prey, or it may search the water and the bottom with its bill. Whichever method it uses, it seizes a wide variety of prey in its long, sharp, yellow bill. Prey of this carnivorous, or meat-eating, bird includes fish, amphibians, reptiles, small mammals, insects, and birds. The heron may live by itself or in small groups.
In the southern part of the heron's range, breeding may occur between November and April. In the north, breeding season is from March until May. Courtship is quite complex among male herons. The male attracts a female by performing a courting dance of strutting and leaping. He also displays and preens his feathers, shakes twigs, and flies in certain patterns. Both male and female grow long, dark plumes on the backs of their heads during the mating season, and their eyes become red. Two other color changes are that the areas between their bills and eyes turn green, and their legs turn pinkish orange. The male and female also playfully poke each other with their bills before mating.
The pair may choose a nest site near others in the colony or away from the others. Nest sites are high in the tops of tall trees. The female lays two to seven large, blue eggs in the nest, which is three feet (one meter) across. Twenty-six to 30 days after being laid and incubated, the eggs hatch. Because some of the chicks are killed by predators, die of starvation, or fall from the nest, only about one-third of the chicks survive to the age of one year. The surviving chicks are able to fly from the nest at two months of age. They may mate when they reach the age of two years.
Crows, ravens, eagles, raccoons, bears, vultures, and hawks may prey on the great blue heron. The life span of the great blue heron is between 15 and 25 years. They are not a threatened species.
Bibliography
The Cornell Lab of Ornithology. “Great Blue Heron Overview.” All About Birds, 2024, www.allaboutbirds.org/guide/Great‗Blue‗Heron/overview. Accessed 8 May 2024.
Polan, Jason. “Great Blue Heron - Audubon Field Guide.” National Audubon Society, 2024, www.audubon.org/field-guide/bird/great-blue-heron. Accessed 8 May 2024.