About us: We own the Wild Birds Unlimited nature shop in East Lansing, Michigan,
a store that provides a wide variety of supplies to help you enjoy the birdwatching hobby.

This blog was created to answer frequently asked questions & to share nature stories and photographs.
To contribute, email me at bloubird@gmail.com.

Saturday, January 18, 2014

New research discovers why birds fly in V formation

PRESS RELEASE: A new study published in the journal Nature has found evidence to suggest that certain birds adopt a V formation while in flight to improve aerodynamics and conserve energy.

In order to fly, birds push air downwards with regular wing movements that generate a vortex within the air; this includes an updraft from the wings that provides lift, while air flowing from the bottom of the wing pushes downward.
Birds time their wing beats to exploit the the vortex and catch a lift from the bird ahead to save energy. Ultimately, geese can increase the maximum distance traveled by as much as 70 percent.

When in this flight pattern, the birds are constantly changing position. The lead bird, eventually, drops to the back when tired and another assumes its place at the front of the V formation. In addition, this setup allows the birds to retain visual contact with each other, ensuring members of the flock are traveling in the correct direction.

The new study gathered information form Portugal and an endangered species of bird – the northern bald ibis (Geronticus eremita), also known as the Waldrapp. The birds are raised in captivity to increase their success and then reintroduced and taught to follow their natural migration route.

Portugal’s research team observed the birds raised in a zoo in Vienna, Austria. In order to “teach” the birds, the team used a parachute aircraft to show them the correct migration route, towards Italy, over the course of several weeks. Before this lesson was delivered, the 14 birds were fitted with small, light-weight data loggers, specially designed by the Structure and Motion Laboratory to collect GPS and acceleration data. This informed the researchers about the position of the birds and what they were doing.

When adopting the V formation, trailing birds would fly along the wingtip path of the bird in front to catch their upwash, thereby easing their flight to reduce energy output. However, when positioned directly behind another northern bald ibis, they do entirely the opposite; under these circumstances, the bird will flap “off beat” to the bird ahead – an action that helps to circumvent the detrimental influence of downwash.

Previously, this form of flight wasn’t considered possible, since it requires – according to the research team – “… complex flight dynamics and sensory feedback.” Precisely how the birds achieve this feat is yet to be definitively confirmed. However, it has been suggested that the ibises employ a combination of highly sensitive wingtip receptors (filoplumes), reflex reaction circuits in the brain and vision to coordinate their movements.

The research could even have implications for the aviation industry. Airlines are dedicating time and money to determine how birds use updraft to their advantage, in the hope that they can use this knowledge.

Press Release
Nature Journal

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