Chornobyl radiation alters the gut microbiome of songbirds

Although nearly 40 years have passed since the disaster at the Chornobyl power plant, its effects are still being studied and felt. Scientists continue to examine the consequences of the catastrophe and the impact of radiation on wild animals because, as Sameli Piirto from the Finnish University of Jyvaskyla states, the consequences of radiological contamination are still unknown.

In the latest study, Piirto and his team examined how radiation affects two common species of songbirds – the great tit and the pied flycatcher. They compared birds living in two zones. The first was in a highly contaminated area, while the second had lower contamination.

In the contaminated area, birds occupied fewer nests, but no differences were found in breeding ecology or the nestlings' health. However, the diet of the nestlings in the contaminated area was more varied. Studies of bird droppings showed differences in the gut microbiome of the birds. Radiation did not affect bacterial diversity but did affect their proportions.

"These results create an interesting background for understanding avian ecology in radiologically contaminated areas. They give us valuable novel information on the effects that radiation has on juvenile birds - an area of research that has been unclear until now," comments Sameli Piirto.

Changes in the microbiome are not the only ones observed in birds living within the Exclusion Zone. In 2011, studies were conducted on 550 birds belonging to 48 species. Birds that lived in the contaminated area had smaller heads and brains. This was due to the persistent radiation hindering their development. Scientists even speculated whether this affected the cognitive abilities of the animals.