City lights blamed for animals' deaths

ARTIFICIAL light from big cities such as London is causing far more damage to wildlife than previously thought, scientists warned today.

A study found that artificial light affects animals' internal navigation systems, causing them to become lost or disorientated. Light reflected from buildings is said to make the problem even worse.

"Environmental cues, such as the intensity of light, that animals use to make decisions occur at different levels of severity in the natural world," said Professor Bruce Robertson, of Michigan State University, who led the study. "When cues become unnaturally intense, animals can respond unnaturally strongly to them. For example, the primary source of horizontally polarised light, which attracts the animals, in nature is water."

The same effect was often seen on black roads illuminated at night, causing major problems. Professor Robertson said: "A dragonfly laying its eggs on a shiny black highway may become paralysed by attraction to the pavement after laying its eggs, effectively dooming its fate and that of its offspring."

His study looked at how several species dealt with both normal artificial light and light reflecting from man-made structures. The professor said white curtains should be added to shiny black buildings to deter insects, bats and birds.