In central Africa, the elephants roam unowned in unfenced territory. Kenya, for example, has tried to stop poachers, but the number of African elephants in Kenya dropped from 65,000 to 19,000 in the first decade the policy was in effect. This encouraged the people to preserve elephant herds so that they could continually benefit from them. Since affirming property rights over elephants, the number of elephants has increased from 30,000 to 43,000. The number of elephants has increased to the point where they are now overpopulated, and excess ivory can be sold in the world market.
Pollution harms private individuals and private property.
The solution is to make companies and individuals culpable for pollution. This includes protesting the private property rights of individuals and companies. When this is hard to determine, e.g. air emissions, the resolution can be found in two possibilities. A tax is levied at that rate. The company then cuts back the pollution to the equilibrium point because it is cheaper to not pollute then to pay that tax.