Grey Heron vs Blue Heron: What are the Differences?

The great blue heron (Ardea herodias) is one of the birds in the Ardeidae family. Although they work slowly, blue herons have impeccable hunting skills. They hunt their prey at lightning speed and are excellent fishers and waders; many of them die by choking while trying to swallow fish too large for their necks. Grey herons, also of the Ardeidae family, have striking similarities to the blue herons, and like the blue heron, the grey heron loves to feed on fish.

Both birds have similar features, and it can be challenging to tell them apart. However, if you watch closely, you’ll find some striking differences. Let’s explore these differences.

Comparing a Grey Heron and a Blue Heron

The Key Differences Between a Grey Heron and a Blue Heron

The most significant differences between grey and blue heron are their size and locality. Blue herons are taller with a larger wingspan and are native to North America, while grey herons are smaller in size than the grey ones and are more centralized in Europe, Asia, and Africa.

Let’s look at other differences below.

Grey Heron vs. Blue Heron: Size and Shape 

Blue herons are taller and weightier than grey herons. They also have long necks that may look shorter because of their striking S shape. While grey herons measure 39 inches in height, blue herons are between 38 to 54 inches tall. Furthermore, grey herons typically weigh between 0.5 to 4 pounds, while blue herons weigh 4.6 to 6 pounds. Generally, the male blue herons and grey herons are larger than females.

Grey Heron vs. Blue Heron: Locality and Distribution 

One of the best ways to tell a blue heron from a grey one is in their distribution. While grey herons are predominantly located in Europe, Africa, and Asia, you may likely find them in North America. However, it would help if you exercised some caution, as herons and egrets can appear where you least expected. For example, you may see a grey heron in North America and a blue heron in Europe. As a vagrant species, grey herons have visited Australia and New Zealand.

On the other hand, blue herons can be found primarily in North America. They can also be found in Southwestern United States, Southern Canada, and in northern parts of South America.

Grey Heron vs. Blue Heron: Rarity

Grey herons are rarely seen in the United States. However, in some cases, people may find these birds when they wander in specific areas. The grey heron has continually increased largely because they are a protected species.

In the UK, their conservation status is “common,” and they’re classified as Green under the Birds of Conservation Concern 4: the Red List for Birds (2021); this is to say that they’re birds of least concern.

The International Union of Conservation and Nature classifies blue herons as a species of least concern. While people can commonly find them in the USA, Mexico, and Canada, there have been sightings in Spain and Southern Europe.

Grey Heron vs. Blue Heron: Habitat

Grey herons love fresh and saltwater environments. You’ll likely find them waiting patiently to catch their prey at the water’s edge. As the generalists they are with their habitat, grey herons may also be found in forests and grasslands. Blue herons are pretty adaptable birds and can be seen in almost any water body. Interestingly, one can find them in their numbers around mangrove swamps, saltwater marshes, ponds, and river banks. They may even forage on dry ground in some cases.

Grey Heron vs. Blue Heron: Plumage 

A person can differentiate a blue heron from a grey heron by the colors of their feathers. The blue heron’s thighs and wrists have cinnamon to rufous-brown colors. Meanwhile, the grey heron is predominantly greyish white-colored on their thighs, belly, and under their necks. Juvenile grey herons don’t have the black plumage highlights that adult grey herons have. It’s important to note that juvenile grey herons may also have some characteristic cinnamon coloration of adult blue herons.

Grey Heron vs. Blue Heron: Bills and Lores 

Grey and blue herons have significantly different bills (beaks) in terms of size. The grey heron’s bill is lighter with a slimmer frame than the blue heron’s. But the blue herons have an orange-colored bill near the base during courtship. When they’re not breeding, one can also differentiate both birds by their lores. The grey heron’s lores are yellow at the bill’s base, turning a darker shade near the eye. Meanwhile, the lore is predominantly dark in the blue heron, with a slight yellow in the middle.

Grey Heron vs. Blue Heron: Legs 

The grey heron and blue heron have different colors on their legs. While grey herons’ legs tend to look pale with dull pinkish or greenish-brown hues, blue herons have two-toned legs. The tarsal region is dark-complexioned in the blue heron, while the tibial region has pinkish coloration.

Grey Heron vs. Blue Heron: Behavior and Calls

One can describe the great blue heron’s calling sound as deep and harsh. They have a lower-pitched voice compared to the grey heron. While grey herons have a lifespan of 5 to 23 years, the oldest blue heron was said to live up to 23 years old.

The photo featured at the top of this post is © Tom Franks/Shutterstock.com