Light Pollution Keeps Fruit Bats From Feasting, Spreading Seeds In Rainforests
Mar 12, 2014 04:00 PM EDT
Light-pollution could be bad news for rainforests.
a recent study was the first to show that seed-distributing bats avoid light-polluted areas, an AlphaGalileo news release reported.
The researchers divided a cage into two parts and left one naturally dark and lit the other with a sodium street lamp. In both sides of the cage the researchers placed pepper plants, nightshade and figs and allowed the bats to choose where to feed.
The team found the bats went into the dark compartment twice as often as the light one.
In a second experiment the researchers shined a light on ripe fruits growing in the wild and recorded how many bats harvested the fruit. The team compared that data with recordings of how many bats harvested the fruit before the light was installed.
When the pepper plants were in the natural darkness 100 percent of them were harvested by the bats; when the fruit was illuminated the bats only harvested percent.
This finding could have serious implications for tropical forest regeneration.
Bats are essential for pollinating plants and spreading seeds by dropping feces on different forest regions. They even help species move into new clear areas.
"In tropical habitats bat-mediated seed dispersal is necessary for the rapid succession of deforested land because few other animals than bats disperse seeds into open habitats," Daniel Lewanzik of the German Leibniz Institute for Zoo and Wildlife Research Berlin (IZW), said in the news release.
Light pollution is increasing in almost every part of the world as both global economies and human populations expand.
"The impact of light pollution could be reduced by changes in lighting design and by setting up dark refuges connected by dark corridors for light-sensitive species like bats," Lewanzik said.