Poaching has traditionally been defined as the illegal hunting or capturing of wild animals, usually associated with land use rights.
According to Encyclopædia Britannica, poaching was performed by impoverished peasants for subsistence purposes and a supplement for meager diets. Poaching was as well set against the hunting privileges of nobility and territorial rulers. By contrast, stealing domestic animals (as in cattle raiding, for example) classifies as theft, not as poaching.
Since the 1980s, the term "poaching" has also referred to the illegal harvesting of wild plant species. In agricultural terms, the term 'poaching' is also applied to the loss of soils or grass by the damaging action of feet of livestock which can affect availability of productive land, water pollution through increased runoff and welfare issues for cattle.
Austria and Germany refer to poaching not as theft, but as intrusion in third party hunting rights. While Germanic law allowed any free man including peasants to hunt, especially on the commons, roman law restricted hunting for the rulers. In Medieval Europe feudal territory rulers from the king downward tried to enforce exclusive rights of the nobility to hunt and fish on the lands they ruled. Poaching was deemed a serious crime punishable by imprisonment, but the enforcement was comparably weak until the 16th century. Peasants were still able to continue small game hunting, but the right of the nobility to hunt was restricted in the 16th century and transferred to land ownership.
The development of modern hunting rights is closely connected to the comparably modern idea of exclusive private property of land. In the 17th and 18th centuries the restrictions on hunting and shooting rights on private property were being enforced by gamekeepers and foresters. They denied shared usages of forests, e.g. resin collection and wood pasture and the peasant's right to hunt and fish. However, comparably easy access to rifles increasingly allowed peasants and servants to poach by end of the 18th century.