Human population growth and human-related activities directly or indirectly contribute to the majority of the causes of biodiversity loss, claims the Rainforest Conservation Fund. In rainforests, land conversion is the main contributing factor for loss of biodiversity. Conversion of rainforest lands to agricultural uses, ranches and urban areas destroys habitats for a variety of plant and animal species. Pollution, global warming and climate change, and forest fragmentation are other causes of biodiversity loss.
The extinction of individual species as well as the spread of invasive species cause biodiversity loss also, reports the International Union for Conservation of Nature. Invasive alien species enter an area where they then spread outside of their normal distribution area, threaten the native species, and shift natural animal and plant patterns. Cats, rats and crabs are some of the most harmful invasive species.
Human consumption of nature and over-exploitation of natural resources through hunting and fishing in unsustainable ways cause biodiversity loss, claims the World Wildlife Fund. Wildlife trade is a major cause of population decline in some species.
Causes of loss in marine biodiversity include fishing and bycatch, hunting, nutrient pollution, coastal development and shifts in migratory patterns, explains SeaWeb. Additionally, increased ultraviolet radiation contributes to aquatic biodiversity loss.