The multiple meltdowns at the Fukushima Daiichi Nuclear Power Plant in March 2011 caused a humanitarian disaster: Upwards of 100,000 people had to be evacuated from within a 20-kilometer ring around the site. But it was also a calamity for thousands of pets left behind. The animals were, of course, traumatized. But researchers have evidence that the Fukushima event was particularly devastating, at least for the estimated 5800 dogs registered in the area. The researchers compared behavior patterns and levels of the stress hormone cortisol excreted in the urine of dogs rescued from the Fukushima exclusion zone with dogs abandoned in another region of Japan. The Fukushima dogs had significantly less aggression toward unfamiliar people, were harder to train, and exhibited less attachment to caregivers than the dogs from the other region , the team reports online today in Scientific Reports. Stress hormone levels were also five to 10 times higher for the Fukushima dogs and persisted for much longer after their rescue. Team member and animal behavior specialist Miho Nagasawa, of Azabu University in Sagamihara, near Tokyo, says it is unclear whether the greater stress resulted from experiencing the earthquake, a longer time before rescue, or the sudden and complete disappearance of humans.
See more ScienceShots .