Bird numbers have dramatically declined in Fukushima , research has revealed . Scientists analysed 57 species in the region and found that the majority of populations had diminished as a result of the nuclear accident . They found that one breed in particular had plummeted from several hundred before the 2011 disaster to just a few dozen today . Researchers have found that bird species are continuing to drop in Fukushima ( shown after the disaster in 2011 ) . The barn swallow , for example , dropped from hundreds to dozens . This is despite radiation levels in the region starting to fall . And comparing it to Chernobyl could reveal what the future holds . The research , published in the Journal of Ornithology , was carried out by scientists at the University of South Carolina including biologist Dr Tim Mousseau . They showed that the situation has steadily worsened since the disaster on 11 March 2011 . On that day , just over four years ago , Japan ’ s Fukushima Daiichi nuclear power plant was heavily damaged by an earthquake and its resultant tsunami . The Fukushima nuclear disaster was a failure at the Fukushima I Nuclear Power Plant on 11 March 2011 . It was caused when the plant was hit by a tsunami , triggered by the 9.0 Tohoku earthquake . This led to three of the plant ’ s six nuclear reactors going into meltdown and releasing radioactive materials . Reports claim the soil and water in the region still contains high levels of radiation which makes the clean-up effort difficult . A total of 300,000 people evacuated the Fukushima area on the east coast and 15,884 people died due to the earthquake and tsunami . Many populations were found to have diminished in number as a result of the accident , with several species suffering dramatic declines . One of the most hard-hit species is the barn swallow , Hirundo rustica , which suffered large population losses due to radiation exposure . ‘ We know that there were hundreds in a given area before the disaster , and just a couple of years later we 're only able to find a few dozen left , ’ said Dr Mousseau . ‘ The declines have been really dramatic. ’ And while background radiation has declined in the region in recent years , the negative effects of the accident on birds are actually increasing . ‘ The relationship between radiation and numbers started off negative the first summer , but the strength of the relationship has actually increased each year , ’ Dr Mousseau said . ‘ So now we see this really striking drop-off in numbers of birds as well as numbers of species of birds . ‘ So both the biodiversity and the abundance are showing dramatic impacts in these areas with higher radiation levels , even as the levels are declining. ’ Dr Tim Mousseau and his team made the findings using thermoluminescent detectors , which use gamma-radiation-sensitive crystals ( shown ) to measure radiation doses in individual subjects living in the wild . One hard-hit species was the barn swallow ( stock image shown ) , Hirundo rustica , which suffered large population losses due to radiation exposure . The team are hoping to get information on what the future holds for Fukushima from the Chernobyl site , which was the scene of a devastating release of radioactive materials in Ukraine in 1986 . One difference noticed so far is that migratory birds fared worse in Chernobyl , whereas it was year-round residents that were doing worse at Fukushima . This could be due to differences in DNA repair capabilities for migratory species as a result of flapping their wings - which lowers their antioxidant levels and makes them more vulnerable to radiation . The Fukushima nuclear disaster was a failure at the Fukushima I Nuclear Power Plant on 11 March 2011 . It was caused when the plant was hit by a tsunami , triggered by the 9.0 Tohoku earthquake . Shown are radiation levels immediately after the accident in 2011 .
Researchers estimate that bird species are continuing to decline in numbers . The bird swallow , for example , ranges from hundreds to dozens . This is despite population levels in the region starting to fall . And comparing it to Chernobyl could reveal what the data holds .