Why are species endangered?
Animals and plants face a large number of different threats with many of them being a direct result of human activity. Some of the most common threats include:
Habitat loss and habitat fragmentation – The ever expanding human population constantly requires additional space and resources. Land is being cleared to harvest products such as timber as well as to make way for human settlement, agriculture and transport links.
Hunting and poaching – A wide variety of animals have been hunted, or fished, beyond sustainable levels and now face possible extinction. Species, such as the tiger, are often hunted because they provide a resource such as food or parts which are used in traditional ‘medicine’. However, some species, such as the cheetah, have been persecuted after gaining a negative reputation for feeding upon livestock or crops or posing a threat to human safety.
Invasive species – Humans have introduced non-native species (both intentionally and accidentally) to a wide variety of habitats, often with devastating consequences. Introduced species may prove highly adaptable and outcompete native species for resources. Introduced predators can decimate local species which are not adapted to avoid predation, for example ground dwelling birds like the kakapo.
Climate change - Droughts, ocean acidification, the loss of sea ice and an increase in storms and extreme weather events can all threaten species’ survival. Sedentary species like plants or specialist species which inhabit small ranges or islands, or those with specific habitat requirements are particularly vulnerable.
Disease – Small populations, especially those which are limited in terms of genetic diversity are particularly vulnerable to disease. Disease can often be spread by domestic animals or accidentally introduced by humans travelling from an affected area to one which had not previously been exposed.
Collection / pet trade – Many animals and plants, such as the Venus flytrap, have been collected from the wild beyond sustainable levels to be sold through the pet trade or be kept in private horticultural collections.
Pollution – Acid rain, heavy metals, pesticides, plastic waste and oil spills all harm the environment and put species at risk. Chemicals are particularly harmful to species that live in water.