An incredible image captured by bird and nature photographer Alan Murphy shows just how inconspicuous nature's top predators can be. A Canadian great gray owl sits perched atop a tree branch, seemingly melting into the background of spruce and pine trees.
"While searching the forests of British Columbia for birds to photograph, I came across this guy. It's like finding a needle in a haystack. See if you can see the Great Gray Owl. Nature is amazing!!" wrote Alan Murphy Photography in a Facebook post. The image shows a great gray owl almost perfectly blending into its forest background. A second side-by-side comparison shows another image of the owl looking towards the camera in which only the outline of its face distinctly pops out against the tree bark.
In British Columbia, Canada great gray owl population levels are considered stable overall. They require healthy trees of coniferous and mixed forests with trees large enough to house their large nests.
"The Great Gray Owl is the worlds largest owl, not by weight but by length," Murphy told IFLScience. Unlike smaller birds who use their camouflage to avoid predators, great gray owls (Strix nebulosa) use their cryptic coloring as a method to sneak up on small prey such as voles, gophers, and other rodents.
"The way they hunt is that they find perches and they stand quietly in one spot. They have really good eyesight, but that doesn't necessarily do the entire trick in order to catch their prey," explained Montana-based avian biologist William Blake to IFLScience. "They have evolved to be extremely well camouflaged in order to have a better time foraging on mammals."
During the nesting period, the male does all the hunting while the female stays with the chicks. Murphy notes that he teaches workshops in the area every year and knows the location of a couple of nests whose inhabitants return annually.
Great gray owls surprise their prey by perching and visually scanning for small clues that give them away along the forest floor.
"Once they see one, the goal is for them to approach them in a very silent manner and their camouflage helps them to not be seen by the prey they’re about to pounce on," said Blake. In the warm months, great gray owls will hunt from low posts or stumps on the ground as they watch and listen for mice and voles. In the snow-covered winter, they hunt from a higher position.
"[The owls] have large facial discs that focus sound. Their ears are asymmetrical (one higher than another) which they can triangulate the sound to pinpoint their prey, even under two feet of snow," explained Murphy. "When the owls head is bobbing and swaying from side to side, they are triangulating the sound in front of them. Once the movement is located under the snow, they will dive down their own body length into the snow to catch the prey."
Overall, North America and Eurasian great gray owl populations are increasing in large parts due to conservation efforts. There are believed to be between 50,000 and 99,000 individuals in the wild today.