Birds' migratory success a complex process

Aug 22, 2005

Magnetic orientation is critical to many birds' migratory success but recent research suggests birds' orientation powers may be more complex than thought.

By studying the influence of light on the ability of migratory birds to orient to magnetic signals, researchers have found clues suggesting birds may be able to interpret magnetic signals by more than one mechanism.

Researchers Thorsten Ritz of the University of California-Irvine and Wolfgang and Roswitha Wiltschko of the University of Frankfurt, Germany, analyzed the orientation behavior of European robins under turquoise light and discovered increasing the intensity of the light changed the birds' orientation significantly, in comparison to dimmer light levels.

The researchers found in dim turquoise light, similar to that found about 33 minutes after sunset, the birds showed normal migratory orientation, with the seasonal shift between southerly directions in autumn and northerly directions in spring.

However, the researchers also found that under brighter turquoise light, corresponding to light levels found 20 minutes after sunset, the birds still orient by the magnetic field, but they no longer show the seasonal change between spring and autumn and, instead, head north in both seasons.

The work is reported in Current Biology.

Copyright 2005 by United Press International

Explore further: World's largest solar boat on Greek prehistoric mission

add to favorites email to friend print save as pdf

Related Stories

Bats use polarized light to navigate

Jul 22, 2014

Scientists have discovered that greater mouse-eared bats use polarisation patterns in the sky to navigate – the first mammal that's known to do this.

The camouflage games: Can you spot the bird?

Feb 20, 2014

So how long did it take you to spot the nightjar in the video on this page? For the predators trying to outsmart their concealed prey it's about not going hungry. But for the birds and the eggs that they ...

Microscopic fountain pen to be used as a chemical sensor

Jan 15, 2014

The Atomic Force Microscope (AFM), which uses a fine-tipped probe to scan surfaces at the atomic scale, will soon be augmented with a chemical sensor. This involves the use of a hollow AFM cantilever, through ...

Recommended for you

A word in your ear, but make it snappy

17 hours ago

To most, crocodiles conjure images of sharp teeth, powerful jaws and ferocious, predatory displays – but they are certainly not famous for their hearing abilities. However, this could all change, as new ...

Understanding the economics of human trafficking

18 hours ago

Although Europe is one of the strictest regions in the world when it comes to guaranteeing the respect of human rights, the number of people trafficked to or within the EU still amounts to several hundred ...

User comments : 0