When it comes to animal and plant life in the Chernobyl Exclusion Zone (also known as the mouthful of a name: The Chernobyl Nuclear Power Plant Zone of Alienation), people's imaginations run wild. They imagine mutated beings with 8 heads, glowing with radiation. But in reality, 35 years after the Chernobyl Disaster, life seems to be getting along just fine without us. So let's take a deep dive into the animals and plants that still live here and see what we can learn.
On 26 April 1986, a reactor in the town of Chernobyl's nuclear power plant had a meltdown during a routine safety check. This caused a massive plume of radioactive contamination to spread through the surrounding air and water, causing issues as far as Sweden and Norway, which were over 1000 km (620 miles) from Chernobyl at the time. Radioactive material contaminated land and water as well, although the effects of that are beyond the scope of this article.
This meltdown is said to have released over 400 times more radiation into the air and surrounding land than the bomb the US dropped on Hiroshima in 1945. It is considered to be the worst nuclear disaster that has ever taken place.
The exclusion zone is 488 square kilometers (189 square miles) and marks only the most harmful of the radioactive areas. Over 100,000 people had to be evacuated after the meltdown, of which only a few people stubbornly remained. Over the next few years, up to 350,000 people were displaced, but many have been able to go home of their own free will in recent years.
Short-term effects of radiation on plants and animals
Shortly after the meltdown, animals and plants died in large numbers or suffered from various mutations. Fasciated daisies have appeared near the site, however, experts warn that fasciation is actually not uncommon in the plant world. That said, the International Atomic Energy Agency (IAEA) claims that there were a variety of genetic mutations, including misshapen leaves of trees and human birth defects, soon after the meltdown. They also reported 1800 documented cases of thyroid cancer found in people 0-14 years old at the time of the accident.
Some of the strongest links to area-related mutations have been smaller brains in birds. There have also been higher rates of cataracts in both birds and mammals. Birds in areas with the highest radiation have also been seen to have damaged sperm or were entirely sterile during the breeding season. Sterility in these areas can affect up to 40% of all male birds. There have also been increased instances of albinism and tumors reported in the area.
The total harm caused seems to be minimized by animals coming from farther away into the exclusion zone, and mating with the animals that survived. This diluted the effects of radiation on the birth defects of many animals. While defects still do happen at a higher rate, the current low levels of radiation make the location far less of a risk.
How are the animals faring now?
Wild animal populations in the area seem to be flourishing in the absence of humans. In fact, a study from 2015 showed that mammal populations in the Chernobyl Exclusion Zone are similar in number to that of nearby nature reserves.
Many animal populations, including endangered animals, have started to make a comeback. These animals include the Eurasian lynx, wolf, brown bear, wild boar, European bison, Przewalski's horse, and the Eurasian eagle-owl. In 2007, The Washington Post even claimed that birds nest on the very reactor that had the meltdown.
This makes the exclusion zone almost like a reserve by default, despite radiation levels being 10 to 100 times higher than normal background radiation. In fact, Ukraine actually designated the area to be a wildlife reserve in 2007 due to the biodiversity present, as well as the lack of people living in the area.
While some areas in the zone still cannot be accessed by humans due to lethal amounts of radiation in the area, many animals in the area have already started to adapt. Radioactivity harms DNA through a process of rapid oxidative stress. As a result, many animals, such as birds, are combating this by creating more antioxidants, such as glutathione.
Plants have also seen similar types of adaptations to defend against the damage caused by radiation. Studies of Arabidopsis, pine trees, as well as seeds and pollen of soybeans and other plants, have shown that their DNA regenerative properties were heightened compared to plants outside of the exclusion zone.
They also are shown to go through hypermethylation, which protects the plants by adding a methyl group to the DNA. This represses certain aspects of gene expression, such as reduced aging, and reduced carcinogenesis.
It's not a bug, it's a feature
That said, not everything is sunshine and daisies when it comes to how life is fairing today in the exclusion zone.
Not as many studies are done on insect populations in the exclusion zone, but of the studies that we do have, the numbers are not good. Insects such as spiders, bumblebees, butterflies, dragonflies, and grasshoppers, are seen in far fewer numbers the higher the radiation gets. The lack of insects is probably due to compromised topsoil in areas where insects generally burrow or eat.
This relative lack of insects has affected other animals in the area that feed on them, thus reducing their number as well. It seems as if the main reason why animals in Chernobyl are "thriving" is due to a lack of humans, despite them still being affected by the radiation in the area.
It was once believed (due to a study in 2005) that barn swallows were not sticking around the area due to being harmed by the radiation. This was later shown to be inaccurate because it was more logical that the swallows did not return due to decreased insect populations.
Checking how radiation has affected wildlife in areas with high levels of radiation is important to understand the environmental impacts of this contamination, so it will be vital to see more studies on animals and plants that live in this area going forward.
Learn a little more by watching the video below!