Extinction Threats are Growing
Many scientists believe that the rate of loss is greater now than at any time in history.
Most scientists agree that human activity is causing rapid deterioration in biodiversity. The loss of critical wildlife habitat, from expanding human settlements, logging, mining, agriculture and pollution are destroying ecosystems, upsetting nature's balance and driving many species to extinction.
For roughly 75 per cent of endangered species, the loss and degradation of their habitat is the central cause of their declining numbers. Illegal poaching and the growing effects of climate change are also threats that species face every day.
http://www.naturecanada.ca/endangered.asp