More recently, eradication efforts have focused on invasive vertebrates as they are the leading cause of extinction of native species, particularly on islands.
In a number of cases, such government endorsed hunting has led to the endangerment or outright extinction of the species.
Alberta, Canada is one of the few non-island places in the world that is free of brown rats.
[2] Since the early 1950s, the Government of Alberta has operated a rat-control program, which has been so successful that only isolated instances of wild rat sightings are reported, usually of rats arriving in the province aboard trucks or by rail.
A number of islands have had programs to remove introduced rats and improve conditions for native fauna.