PATRICK PLEUL/AFP/Getty Images
Spix's macaws (L-R) Felicitas, Frieda, Paula and Paul sit on a branch in their aviary at the Association for the Protection of Endangered Parrots in Schoeneiche, Eastern Germany, on October 11, 2011.
Birds in flight often arrange themselves in aerodynamically optimum positions, according to a new paper in thejournal Nature
that helps to explain how birds fly in such impressive formations. Lead researcher Steven Portugal and his colleagues focused their study on northern bald ibises, but many bird species also exhibit the amazing flight behavior. Portugal, a University of London Royal Veterinary College researcher, told Discovery News that birds could be using three things to achieve their flying precision: "(1) vision – watching the bird in flight to get all the information they need, (2) feathers – sensing the changes in pressure, wind etc. through their flight feathers, and (3) positive feedback – i.e. they just fly around and when it feels easier/better they stay in that position."
The researchers determined that birds try to find "good air," meaning airflows (not just wind, but even the air created by other flapping wings) that minimize their energy expenditure and help them to get where they plan to go. Conversely, birds avoid regions of "bad air" that could work against them.
Many birds fly in distinctive V-formations. Portugal said, "The intricate mechanisms involved in V formation flight indicate remarkable awareness and ability of birds to respond to the wing path of nearby flock-mates. Birds in V formation seem to have developed complex phasing strategies to cope with the dynamic wakes (turbulent air) produced by flapping wings."
H.K. Job, Wikimedia Commons
Military planes sometimes fly in what is known as an "echelon formation," which mirrors nearly the exact same flight formation of many birds. This particular bird version is a variation of the "V," only with a rounded edge.
The U.S. Navy's famous flight demonstration squadron The Blue Angels often flies in a trademark "diamond formation" once popularized by fighter-bomber pilots. In it, the pilots maintain an 18-inch wing tip to canopy separation. Birds can fly even more tightly together.
The term "murmuration" refers to a flock of starlings. These birds can create dramatic patterns in the sky, such as this one over marshlands near Tønder, Denmark. Other small birds, such as sandpipers, may also create what look to be dazzling aerial ballets in the sky as they fly en masse.
Rupert Ganzer, Flicker
Even birds flying very close to land can do so in remarkable unison. Here, a formation was photographed as the birds flew over the beach at Camperduin in the Netherlands.
Daniel Jolivet, Flickr
The classic "V" formation has all sorts of variations. In this case, three separate -- yet united -- groups create an arrow-like effect in the sky.
Mark Kent, Flickr
Alfred Hitchcock's classic horror film "The Birds" included many scenes where numerous birds blanketed the sky. Up close, these starlings look small and harmless but, as a huge murmuration, their power becomes evident.
From the earliest planes to those in design today, aircraft have been modeled after birds. It's no wonder. Every inch of this sleek northern bald ibis, snapped while flying over Tuscany, adds to the bird's flying prowess. Its 53-inch wingspan and powerful, synchronized wing beats must have captivated people in the ancient world too, since ancient Egyptians and other early cultures featured the birds prominently in their artwork and legends.
No Disney ending here: A rare blue parrot named Presley died last week, leaving only one known, wild-born Spix's macaw left. And, unlike in the movie "Rio," which Presley may have inspired, he didn't leave behind any offspring.
The native Brazilian birds are already believed to be extinct in the wild, after deforestation and non-native honeybees started competing with them for nest space. The last sighting of a Spix's macaw in the wild came in 2000.
Fewer than 100 of the parrots are currently being bred in refuges, and the lack of genetic diversity has led to challenges for them. Some researchers hope advances in artificial insemination could help restore the population, according to Doha News.
"Just looking after birds in a cage is not conservation," Al Wabra Wildlife Center director Cromwell Purchase told the website.
In the Disney film "Rio," the macaw returns to Brazil and finds the last remaining Spix's macaw -- conveniently, female. Overcoming poachers, they reproduce in the fairy-tale ending. Director Carlos Saldanha has said he hoped the Disney movie would help inform its audience about endangered birds, according to National Geographic.
"I wanted [to feature] the rarest bird," he told the website Bird Channel in 2011. "The Spix's macaw truly is the rarest."