How Big Are Great Grey Owls? (Wingspan + Size)

Great Grey Owls (Strix nebulosa) are found in both the western and eastern hemispheres, including parts of the northern USA and Canada, Russia, and northern Asia.

This cold-dwelling bird is exceptionally hardy and can survive plunging Arctic winter temperatures. So, how big really are Great Grey owls?

The Great Grey owl is colossal, the world’s largest owl by length. They measure around 61 to 84cm (2.0 to 2.7ft) long with a wingspan that exceeds 152cm (5 ft 0 in). However, they’re not particularly heavy, weighing between 1 to 1.5kg (2.2 to 3.3lb) in most cases.

Like many owls and other birds of prey, the female is larger than the male. Despite the enormous size of this owl, the majority of its size and weight is accounted for by its plumage, rather than its actual body.

The body is relatively small, which explains why this owl is quite light for its size. Most similar-sized eagles weigh at least 2 kg.

There’s a lot more to discover about this intriguing owl - so read on to find out!

Great Grey Owls are the largest species of owl by length

Great Grey Owl wingspan

The Great Grey Owl has a wingspan of up around 152 cm (5 ft 0 in), with an average of 142 cm (4 ft 8 in) for females and 140 cm (4 ft 7 in) for males.

Due to its large wingspan, the Great Grey owl is a very powerful flier and can fly in heavy snow and effectively hunt in adverse conditions. The Great Grey Owl can fly quickly and quietly, which allows it to effectively ambush its prey, even despite its massive size.

Moreover, they are very silent flyers and can hunt in complete darkness due to their exceptional hearing. They can hear moving prey beneath 60cm of snow and will “snow plunge” to catch food from under the snow cover.

Great Grey Owl wingspans can reach up to 5ft

Great Grey Owl weight

The average weight of a Great Grey owl is around 1.0 to 1.59kgs (3.5lbs). Like most other owls, females are typically larger than males and sit at the top of the range, whereas males sit at the bottom of the range.

Great Grey owls are one of the largest owl species in the world, but they aren’t that heavy, as most of their size is made up by their thick plumage.

For example, compare the Great Grey owl to the similarly-sized Great Horned owl or Eurasian Eagle-owl. The latter two species are marginally larger but weigh around 2.5kg on average, with a max weight of around 4 kg - that’s more than double the Great Grey owl!

Great Grey owls can catch large prey such as grouse and ducks. Although their diet consists mostly of small mammals - especially lemmings - Great Grey owls will also eat birds, reptiles, and sometimes fish.

Despite being one of the largest owls in the world, they aren't that heavy, as their thick feather plumage gives them considerable size

How big are Great Grey Owls compared to a human?

Great Grey owls are one of the largest owl species in the world. They are roughly about half the size of a human - which is still pretty big.

On average, they are about 76.2 (30in) tall, but some may measure up to 85cm (33in). The wingspan measures up to 5ft. In comparison, the average human is about 152.4cm (60in) to 182.9cm (72in) feet tall.

How big of an animal can a Great Grey Owl pick up?

Great Grey owls are large birds capable of catching prey such as grouse, geese, ducks, voles, and hares. However, despite their size, they’re not particularly heavy and lack the strength of other large non-owl birds of prey.

They much prefer to catch small mammals like lemmings and voles, which form the staple of their diets. They certainly lack the lifting power of eagles and large hawks.

Great Grey Owl hunting for prey in its natural habitat

Why are Great Grey Owls so big?

Great Grey owls live in the far north, including remote tundra regions just outside of the arctic circle. Their boreal habitats require them to keep an ultra-thick layer of plumage, which accounts for this owl’s large size.

The Great Grey owl's body is actually very small. If you compare this owl to other similar-sized owls and other birds of prey, it’s almost half as heavy!

So, the Great Grey owl is somewhat of a small owl in a large owl’s clothing. That doesn’t make them any less impressive, though.

Great Grey Owls need a thick layer of plumage to survive in their harsh habitats

Great Grey Owls compared to other bird species

Great Grey owls, Snowy owls, Great Horned owls, and Eagle owls are all pretty similar in size and stature.

However, the Great Grey owl is significantly lighter than the other two. In terms of wingspan, the Great Grey owl is up there with small to medium-sized eagles.

Close up of a Great Grey Owl perched in a tree

FAQs

Are Great Grey Owls the biggest owl in North America?

The Great Grey Owls are the tallest owls in North America by length. However, when it comes to weight, the Great Grey owl is overtaken by the Great Horned owl and Snowy owl.

They’re still exceptionally larger and have the largest facial discs or ‘radar dishes’ of any owl.

Can a Great Grey Owl pick up a human?

They might look large and menacing, but Great Grey owls actually only weigh 1.0 to 1.5k (2.2 to 3.3lb). This is very light for a bird of their size. That’s because this owl’s size mostly consists of thick feathers rather than its body!

Can a Great Grey Owl pick up a dog?

A Great Grey Owl probably can’t pick up most dogs. These owls weigh about 1.0 to 1.5kg (2.2 to 3.3lb) and mainly hunt lemmings, voles, and small-to-medium-sized birds (the biggest probably being a small goose).

Which is bigger, Great Horned Owl or a Grey Owl?

The Grey Grey owl is a similar size to Great Horned Owls, though they generally weigh much less.

In fact, both the Snowy owl and Great Horned owl can weigh double the Great Grey owl.