Chornobyl's lingering effects: How radiation alters songbirds' microbiomes

Although nearly 40 years have passed since the Chornobyl power plant disaster, its effects are still being studied and felt. Scientists continue to examine the disaster's impact and the effect of radiation on wild animals because, as Sameli Piirto from Finland's University of Jyväskylä claims, the consequences of radiological contamination are still unknown.

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

In the contaminated area, birds occupied fewer nests, but no differences were found in the breeding ecology or the health of the chicks. However, the chicks' diet in the contaminated area was more varied. The study of bird droppings revealed differences in the gut microbiome of the birds. Radiation did not affect the diversity of bacteria, but it 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 findings in birds living in the Exclusion Zone. In 2011, studies were conducted on 550 birds belonging to 48 species. Birds living in the contaminated area had smaller heads and brains. This was caused by the persistent radiation hindering the development of the birds. Scientists even speculated whether this affects the cognitive abilities of the animals.