A goose flying upside down was showing off, experts have said.
Goose
Amateur photographer Vincent Cornelissen posted an image on Instagram of the goose cruising upside down in the Netherlands earlier this year.
Many users questioned what the bird was doing but Cornelissen reassured them that the flying creature was fine and was simply trying to impress its mates.
The goose was performing a manoeuvre known as whiffling which is when the animals rapidly descend and zig-zag in the skies, which is thought to be a defence against predators.
Cornelissen wrote on the social media site: "They do it to brag to their peers. Like, look at me!"
The photographer revealed that the unique image of the goose had even been used to help teach university students.
He said: "There was even a professor from Istanbul University who edited my photo with arrows to teach his students about aerodynamics."