Many humans believe that certain wild animals pose a serious threat to their livestock. In response to this threat, they have tried to retaliate. Because of this, the Grizzly Bear disappeared from much of the United States, including in California, where it is the state animal. The wolf has vanished from much of Europe and North America. In Tasmania, the Thylacene Wolf was also persecuted, and its habitat overrun. The Bald Eagle, national symbol of the USA, is still chased down by people in America. Helicopters have sometimes been used to pursue them.
Coyotes are often regarded as pesky animals that endanger the lives of domesticated animals. No matter what humans try to do, its species only seems to evolve and change according to its surrounding conditions. The flexible adaptivity of coyotes, including an uncanny ability to increase reproductive rate when pressured, allows them to survive. Sheep raisers once encouraged the use of chemical poisons against coyotes, which killed much other wildlife in the region until the President stopped them in 1972. However, these methods sometimes created larger coyote populations. When they did successfully get rid of the coyotes, however, it was found that ground squirrels began to eat the sheep's grass. You guessed it - the ground squirrel populations had previously been controlled by the coyotes.
In addition to these occurrences of overexploitation, hunting, collection, trade, and predator control, the direct hunting of wildlife has been augmented by damage or destruction of the ecosystem in which the animal lives (see Indirect Causes). These indirect causes are perhaps the most severe means of wildlife extinction.