Photograph Credit: Roberts W. French Jr.

The Great Grey Owl: Phantom of the North

The birds of prey are among the most renowned of nature’s predators. Mankind has long been aware of their fantastic predatory abilities, and as such has revered these animals for thousands of years. These powerful birds, recognized for their deadly skill and strength, were integrated into the symbolism, mythology, and religions of various cultures past and present. This fascinating group consists of a variety of different birds, including eagles, falcons, secretary birds, and even vultures. However, among the most interesting members of the group are the owls. With their unique design, including large, forward-facing eyes and flat faces, it is not difficult to tell owls apart from other birds of prey. Their adaptations make them superb predators, allowing them to fly silently through the dark of the night and swoop down on their targets before the prey can even react. One species in particular possesses both this silent hunting ability and an interesting spectral design which has aptly earned it the haunting title, “Phantom of the North.” This creature is none other than the great grey owl, one of the larger members of the owl order, Strigiformes. With its ghostly characteristics and graceful hunting abilities, the great grey owl almost resembles a creature of myth or legend. However, this adept predator is indeed very real, and among the most beautiful of nature’s great predators.

The great grey owl (Strix nebulosa) is a fairly large and impressive owl, reaching a body length of 24-33 inches along with a wingspan of 4.5-5 feet. It is, however, a rather lightweight creature for its size, reaching a maximum of only 3 lbs.[1] Furthermore, the males of the species are larger than the females.[2] As one might gather from the common name of the species, great grey owls possess a grey coloration consisting of a combination of light and dark patterns. They possess somewhat large heads (even in comparison to other owl species) as well as unusually long tails relative to other owls.[3] Great grey owls are also known for their large, distinctive facial disks, with two obvious grey concentric circles. The feathers of the facial disk play a special sensory role in that they direct sounds toward the owl’s ear openings, which are hidden from view by the bird’s plumage. In addition to this facial disk and predominantly gray coloration, the great grey owl has a black chin spot along with two white-feathered mustaches and a prominent white collar on the front of the neck. Though their yellow eyes appear rather small in comparison to their heads (the bird’s plumage makes the head appear larger than it actually is), great grey owls possess excellent vision. This, combined with their keen hearing, special facial disk feathers, and the ability to rotate their heads three quarters of a circle (270 degrees), makes locating distant prey an easy task for these owls. Approaching and capturing their prey is also of no difficulty, as the soft feathers of the owls allow them to fly silently towards their targets without being noticed. Like other birds of prey, great grey owls also have sharp talons that allow them to effectively seize their unwary prey. All of these special adaptations come together to produce a predator that is just as efficient as it is complex.[4]

The great grey owl's facial disk contains feathers which direct sounds into the owl's ears, allowing it to accurately locate hidden prey. Photograph Credit:

Though great grey owls can be difficult to detect due to their often silent nature, the species actually possesses quite a widespread range. These owls can be observed in northern United States, Canada, Alaska, northern Europe, and Asia.[5] Within this generous range, the owls enjoy a fair amount of variety in their habitats. They prefer dense taiga, boreal, or mountainous forests interspersed with open meadows, clearings, or bogs.[6] Nesting owls often move to mature poplar woodlands, which distances them further from human activity and provides their eventual offspring with a greater degree of safety.[7] These owls are not considered migrational birds, though in some locations seasonal changes will cause some owls to relocate to other areas. Rather, they are described as being nomadic. Instead of relocating due to seasonal changes, most great grey owls move based on the supply of their needs. That is, once they determine that an area is no longer providing them with the resources they require (such as food), they will leave behind their current environment and move to a new area that will sustain them.[8]

Great grey owls can hunt effectively both day and night, an ability that allows them a greater span of time to search for and hunt prey. Like other owls (and birds of prey in general) they enjoy a varied diet of small animals thanks to their larger size and hunting ability. They mainly prey on small rodents such as mice and voles, but will also hunt rabbits, squirrels, weasels, frogs, snakes, and occasionally even other birds. When searching for prey, a great grey owl perches on a tree overlooking a meadow or sufficiently open area. Though they possess excellent vision, these owls rely greatly on their keen hearing when it comes to finding their prey. This is due to the fact that they often inhabit areas with snowfall, meaning that the owl’s prey is commonly hidden from view under snow. Recall that the feathers which make up the owl’s facial disk aid in the direction of sound to the bird’s ears. This allows the owl to hear the sounds made by a hidden mouse even under two feet of snow. Thus, the owl is able to accurately determine the location of its hidden prey before it even truly begins the hunt. Upon locating its target, the owl takes off from its perch and silently glides to the prey’s area. It prepares itself for the attack as it nears its target, which is completely oblivious to the approaching danger. The owl then plunges into the snow and clutches the prey in its sharp, powerful talons. At this point, escape is nearly impossible for the prey, and the owl flies back to a safe area with its new meal. “Plunge marks” are often produced in the snow as a result of this hunting style, with some of these marks even showing an imprint of the owl’s outstretched wing feathers where the owl dropped into the snow. These markings are very useful in that they are often the only indications that this reclusive species is present in the area.[9] Owls often consume small prey whole and later regurgitate what is called an “owl pellet,” a hard, grey pellet about three inches long that consists of the bones, feather, and fur of the birds’ prey held together by the owls’ body fluids. Educators often dissect these pellets for students to observe what owls eat.[10]

Though adult owls are not threatened by many predators, owlets can be killed by other large owls, marten, and black bears. Adults are also preyed upon by the Canadian lynx (Lynx Canadensis).[11] The great horned owl (Bubo virginianus), another large and powerful owl species, is a fierce predator that will sometimes hunt great grey owls, though both owl species are often harassed by ravens and other small birds.[12]

Great grey owls reach sexual maturity at the age of three years[13], with breeding taking place in late winter. The male prepares for the breeding season earlier in the spring by performing aerial displays and bringing food to the female. The pair may not actually breed, but when they do, they locate an abandoned hawk or crow’s nest. Here, the female lays 2-5 dull white oval eggs in March-June. Different factors come into play during reproduction. Firstly, the temperature range may delay egg-laying, especially in deep snow years. Secondly, the number of eggs produced depends on the abundance of food. During years with an abundance of mice, owls tend to lay more eggs and more young survive the nestling stage. The eggs are incubated by the female for a period of 28-29 days. The owlets hatch covered in soft white down and with their eyes open. During this fragile stage, the owlets are entirely dependent on their parents, which provide them with food. The food is torn into small, manageable pieces that the young owls can easily consume. As days go by, the owlets begin to lose their down and grow feathers in their place. During this time, the young become quite adventurous as they begin to respond to their natural flying instincts. They soon begin to take part in pre-flight exercises by walking around the top of their nest while flapping their wings. They also approach the edge of their nest and continue the wing-flapping exercise while strongly gripping the edge of the nest with their talons.[14] They may even attempt to take flight, only to glide down clumsily and climb back up to the nest. Yet with practice eventually comes mastery, and the owls are soon able to take to the skies like their parents.[15] After about a month, the young owls become independent and leave their parents to fend for themselves.[16] The parents remain together for life, continuing to raise more offspring together in future breeding seasons. Owls do not possess particularly long life spans in the wild, living only about 10 years. Their life span more than doubles in captivity, however, with captive great grey owls being capable of living for up to 40 years.[17]

This species' reclusive tendencies and silent nature make it a rare sight. Photograph Credit: D. Chalfant

Great grey owls are not globally threatened. Though population numbers fluctuate annually as a result of food availability, they remain relatively stable over longer periods.[18] However, the U.S. Department of Interior Bureau of Land Management considers the great grey owl to be a sensitive species and it is thus protected in the United States on both federal and state levels. The species has also been the subject of extensive management studies, which have provided more information concerning its environmental needs. It is well understood that the great grey owl is very vulnerable to human disturbance such as the clearing of forests for timber and farming, as this robs them of potential nest sites, among other basic needs. Indeed, the availability of nest sites is the main limit to the species’ distribution. Yet another factor which can negatively impact the great grey owl is the damaging of its food chain; chemicals used in exterminating mice and other pests have severely limited the food supply of the owls. Keeping the population numbers of these owls in important, as the species contributes to an ecological balance through its predation on rodents as well as occasional scavenging on carrion.[19]

“The Phantom of the North” lives up to its name, as the great grey owl’s distinct appearance and shy, reclusive nature make it a rare yet beautiful sight. It is also a prime example of the grace and power that can be observed among the birds of prey, as this fascinating animal possesses a variety of adaptations which have turned it into a truly masterful hunter. It is thus no wonder that these creatures were revered by ancient human civilizations and continue to capture the fascination of countless people today. Even among its fellow birds of prey, this silent, spectral predator truly stands out as a magnificent creature.

[1] “Great Grey Owl.” (accessed March 24, 2012).

[2] Amsel, Sheri. “Owl (Great Gray).” (accessed March 24, 2012).

[3] “Great Gray Owl.” (accessed March 24, 2012).

[4] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).

[5] Amsel, Sheri. “Owl (Great Gray).” (accessed March 24, 2012).

[6]  “Great Grey Owl.” (accessed March 24, 2012).

[7] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).

[8] “Great Gray Owl.” (accessed March 24, 2012).

[9] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).

[10] Amsel, Sheri. “Owl (Great Gray).” (accessed March 24, 2012).

[11] Ibid

[12] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).

[13] “Great Grey Owl.” (accessed March 24, 2012).

[14] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).

[15] Amsel, Sheri. “Owl (Great Gray).” (accessed March 24, 2012).

[16] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).

[17] Amsel, Sheri. “Owl (Great Gray).” (accessed March 24, 2012).


[18] “Great Grey (Gray) Owl.” (accessed March 24, 2012).

[19] Tonk, Rohit. “Strix nebulosa.” (accessed March 24, 2012).