Birds living around the site of the Chernobyl nuclear accident have 5% smaller brains, an effect directly linked to lingering background radiation.

Birds living around the site of the Chernobyl nuclear accident have 5%
smaller brains, an effect directly linked to lingering background
radiation.

The finding comes from a study of 550 birds belonging to 48 different
species living in the region, published in the journal PLoS One.

Brain size was significantly smaller in yearlings compared to older birds.

Smaller brain sizes are thought to be linked to reduced cognitive ability.

The discovery was made by a team of researchers from Norway, France
and the US led by Professor Timothy Mousseau from the University of
South Carolina, US, and Dr Anders Moller from the University of
Paris-Sud, France.

Harmful legacy

In April 1986, reactor number four at the Chernobyl Nuclear Power
Plant exploded.

After the accident, traces of radioactive deposits were found in
nearly every country in the northern hemisphere.

An exclusion has since been set up around the site of the accident.

However, scientists have been allowed inside to gauge the impact the
radiation has had on the ecology of the region.

Last year Prof Moller and Prof published the results of the largest
wildlife census of its kind conducted in Chernobyl - which revealed
that mammals are declining in the exclusion zone surrounding the
nuclear power plant.