Herons are large freshwater birds that are best known for their long-legged and long-necked appearance. There are more than 60 recognized species of herons in the world and they can be found on every continent except Antarctica. Grey herons and great blue herons are some of the most common, with great blues herons being the largest herons native to North America. At first glance they can look quite similar, but luckily there are actually some distinct differences that we can use to tell the two apart. So join us as we take a closer look at grey herons vs great blue herons.
Comparing Great Blue Heron vs Grey Heron
Grey herons and great blue herons are both members of the Ardeidae family group. There are four subspecies of grey herons and five subspecies of great blue herons. The great blue heron subspecies Ardea herodias occidentalis is native to Florida and the Caribbean islands and was originally classified as a separate species and known as the great white heron.
|Great Blue Heron||Grey Heron|
|Species Name||Ardea herodias||Ardea cinerea|
|Size||Height – 45 to 54 inches|
Length – 36 to 54 inches
Wingspan – 66 to 79 inches
|Height – 40 inches|
Length – 33 to 40 inches
Wingspan – 61 to 77 inches
|Distribution||North America, Central America||Europe, Asia, parts of Africa|
|Habitat||Virtually any wetland habitat||Any wetland habitat shallow enough to wade in|
|Plumage||Gray neck, black and white down the front. Light colored head with white face. Grayish-blue flight feathers, reddish-brown thighs, reddish-brown and black stripes on flanks||Grey body and wings, some black on flanks. White head and neck with black stripe extending from eye|
|Bill||Dull yellow. Orange at beginning of breeding season||Long, straight, pinkish-yellow|
|Legs||Grey outside of breeding season, orange during||Brown|
|Diet||Primarily small fish, but also larger fish, crabs, rodents, reptiles, and amphibians||Fish, frogs, toads, insects, small mammals, juvenile birds|
|Predators||Adults: bald eagles|
Juveniles and eggs: turkey vultures, ravens, crows, hawks, black bears, raccoons
|Adults: no main predators|
Juveniles and eggs: crows and kites
|Lifespan||Average 15 years, oldest approximately 25 years||Average 5 years in the wild, but oldest recorded 23 years 9 months|
The 4 Key Differences Between Grey Herons and Great Blue Herons
Grey Heron vs Great Blue Heron: Location and Habitat
The most important difference between grey herons and great blue herons is their location which is key to determining which species is which. Grey herons are widespread across Europe, Asia, and parts of Africa, where they live in any wetland habitat with water that is shallow enough for them to wade in. If the body of water is deeper, then the key is that there must be shallower areas that are suitable for them. They usually nest in high trees near to the water, although other nesting locations include trees, bushes, cliff edges, and bramble patches. Grey herons are largely absent from the Americas, although recently there has been some sightings of them on islands off the coast of North America.
As we mentioned earlier, great blue herons are the largest herons native to North America. They are widespread across much of North and Central America where they live in virtually any wetland habitat. Great blue herons rarely ever venture far from water and they often nest in trees and bushes near the waters edge. They are hardy birds and can survive the cold northern winters so long as their fishing grounds do not freeze over.
Grey Heron vs Great Blue Heron: Size
One of the main things to look out for when distinguishing between these two stunning birds is their size. To put it quite simply, great blue herons are much larger than grey herons. Grey herons are 40 inches tall and have a length of between 33 and 40 inches. They also have a wingspan that between 5ft and 6ft 5ins wide and weigh no more than 4 pounds, 10 ounces.
Great blue herons are almost twice as heavy with weights up to 7.9 pounds. They also have a larger wingspan of 5ft 6ins to 6ft 7ins. Additionally, they are 36 to 54 inches long and 45 to 54 inches tall. Great blue herons exhibit sexual dimorphism whereby males are larger than females, although this difference is not great.
Grey Heron vs Great Blue Heron: Appearance
Another distinctive difference between grey herons and great blue herons is their color. Grey herons have a white head and neck with grey bodies and wings. They also have some black plumage on their flanks and wings, as well as a black stripe on their head which extends from the eye and a pinkish-yellow bill which is long, straight, and powerful. Juveniles are a more greyish color and they lack the dark stripe on their heads.
Great blue herons have grayish-blue flight feathers with reddish-brown and black stripes on their flanks. They also have a grayish colored neck with black and white markings down the front of it and a light colored head with a white face. Possibly the most distinctive markings on great blue herons are their thighs which are reddish brown. They also have a large bill which is a dull yellow color.
Grey Heron vs Great Blue Heron: Legs
Another noticeable difference between these two herons is the color of their legs. Great blue herons have gray legs outside of the breeding season, during which their legs turn orange. However, grey herons have brown legs all year around.
The photo featured at the top of this post is © Angyalosi Beata/Shutterstock.com
FAQs (Frequently Asked Questions)
How many chicks do grey herons and great blue herons have?
Both grey herons and great blue herons lay between 3 and 6 eggs every year. The incubation period of grey herons is 25 days while great blue herons incubate their eggs for around 27 days. Great blue herons chicks hatch out over several days, with the chick that is born first generally becoming the strongest. This is because the first born tends to grow the quickest and be the most aggressive at feeding time.
Do grey herons and great blue herons mate for life?
No, unlike many other birds, grey herons and great blue herons do not mate for life. Instead, they go through elaborate courtship rituals but usually only remain together for one breeding season.
Do herons nest in colonies?
Yes, both great blue herons and grey herons nest in large colonies of up to several hundred birds. Nesting in colonies gives the young chicks greater protection against predators.
Do grey herons live in cities?
Yes, it is not uncommon to see grey herons in large cities. This is because they are extremely adaptable and are capable of living in urban areas so long as there is a suitable body of water for them and plenty of food.
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