I read an interesting book by an American woman who spent a year in the region of Chernobyl. She was mostly interested in tracking the effect on animal life. What she found astounded her. Bird flocks were so numerous that the sky was dark at time, horses, sheep, wolves, etc, etc, were thriving and prospering.
The Hanford Nuclear Reservation in SE Washington State is similar in regards to wildlife. BECAUSE it's off limits to humans it's turned into a sanctuary.
While I'd hate to see the world reduced to Chernobyls or Hanfords, at least there's hope that life will continue on this planet should mankind kill itself off.