Decreasing numbers of organisms, and consequently their extinction due to various factors, they are:
destruction and transforming the environment by human activity causes-including too large and rapid exploitation of natural resources water pollution and the lowering of the water heated industrial water adversely affects the propagation of animal species and alter significantly the living conditions of organisms occurring there, which can lead to their death! Construction of highways and roads without regard to the migration routes of animals mechanization of forest and field. Many species loses its habitat, because the man cut the forests and changing them on the fields, it occupies the area under construction, and transport routes zaoruje lakes. The burning of dried tra contributes to the death of many species of plants and animals living in soil collection of plants for decorative purposes, industrial and commercial.