Snakes can show Fukushima radioactivity

SNAKES could be used to measure radiation levels near Fukushima, the site of three reactors damaged in the 2011 tsunami.

Efforts to decontaminate the site have been hindered by radioactivity and measuring it remains a challenge following the second-worst nuclear disaster in history.

University of Georgia scientists have discovered that rat snakes can perform a role like canaries do in a coal mine. They could be released in a certain area and then studied for signs of radioactivity, the researchers said.

“Snakes are good indicators of environmental contamination because they spend a lot of time in and on soil,” said James Beasley, one of the scientists. “They have small home ranges and are major predators in most ecosystems.”

Transmitters were attached to nine snakes and their movements were tracked using GPS and high-frequency radio signals. This enabled researchers to track where the snakes were and how far they were travelling.

The team used 1,718 locations in the Abukuma Highlands, near the Fukushima Daiichi Nuclear Power Plant. Scientists found that the snakes only travelled short distances, at times as little as 71 yards. During the winter they sheltered underground, increasing their exposure to heavily contaminated soil.

Their relative immobility enables the snake to accumulate high levels of radionuclides in its body. These are the unstable radioactive elements that scientists could then measure to determine levels of contamination in the soil.

Scientists believe snakes are better indicators of contamination than more mobile creatures like wild boar, songbirds or East Asian raccoon dogs that travel greater distances.

A study last year discovered a correlation between the levels of radiocesium in the snakes and the amount of radiation in the soil.

“Our results indicate that animal behaviour has a large impact on radiation exposure and contaminant accumulation,” says Hannah Gerke, the study’s lead author.