Skip to content

How does deforestation affect biodiversity?

Forests contain some of the richest concentrations of biodiversity on the planet. But between 1990 and 2020, around 420 million hectares of mainly tropical forest has been lost and  a further 10 million hectares, an area the size of Scotland and Wales combined, is being lost each year. Without the shelter, food and water the forests supply, the many thousands of species that coexist within and beneath the canopy of trees also vanish. 

Forests are home to a huge array of different tree, amphibian, bird and mammal species but they are facing a combination of threats. The Amazon – the world's biggest rainforest – has an estimated 15,000 species of trees, an estimated 3,000 species of fish in the river system and there are currently 1,300 described species of birds. But about 17% of it has been deforested.

Logging for timber and the clearing of tropical and subtropical forests to make way for agriculture and grazing are the two main causes of destruction to forest habitats. Fire is also a major threat to forests. In rainforests such as the Amazon, fire is usually used to clear land for farming. 

Much of the tropical and subtropical forest that remains around the world has become fragmented, with 20% of global forest scattered across 34 million smaller patches affecting species that require large territories, but also increasing the isolation of animals and plants, limiting their gene pools.

Despite the huge annual losses caused by deforestation, there have been some improvements in keeping some parts safe. Some tropical rainforests, subtropical dry forests and temperate oceanic forests are now located within protected areas, including indigenous reserves, with studies showing these are often capable of slowing deforestation.

Forest loss does not simply mean all biodiversity is wiped out, but it often results in a significant change in the mix of species that live there since some species will thrive while others will be lost. So-called generalist species such as some deer, foxes and white storks have been seen to increase in forests that have been disturbed by human activity. Small, light -loving plants can also flourish in cleared patches of forest.

To find out more: Amazonia’s future: Eden or degraded landscapes? | Royal Society; Past and future decline and extinction of species | Royal Society

Find answers to 16 key questions about biodiversity

  • Introduction

    At its simplest, biodiversity describes life on Earth – the different genes, species and ecosystems that comprise the biosphere and the varying habitats, landscapes and regions in which they exist. We've answered some of your most popular questions about biodiversity.

    Find out more

  • What is biodiversity?

    Biodiversity is all the living things on our planet – from the smallest bacteria to the largest plants and animals. So far, we have identified around 1.6 million species but that is probably only a small fraction of the forms of life on Earth.

    Read the full answer

  • Why is biodiversity important?

    Biodiversity is essential for the processes that support all life on Earth, including humans. Without a wide range of animals, plants and microorganisms, we cannot have healthy ecosystems.

    Read the full answer

  • How do we measure biodiversity?

    There is still much we do not know about the complexity of biodiversity on Earth. There are a number of ways that we measure it, with counting species the most common approach.

    Read the full answer

  • What is the scale of biodiversity loss?

    The list of known recent extinctions is still a small fraction of all species on the planet but it is far above prehuman levels and the evidence suggests it is rising fast.

    Read the full answer

  • We regularly hear of new species being discovered - does that not offset the loss of existing species?

    Every year thousands of previously unknown species are discovered, described and named.

    Read the full answer

  • Where is most biodiversity loss happening and why?

    Biodiversity loss has been most pronounced on islands and in specific locations around the tropics.

    Read the full answer

  • Is the rate of biodiversity loss increasing or decreasing?

    Compared to the 1.6 million species known about on Earth, the number of recorded extinctions can seem very low.

    Read the full answer

  • What is the state of biodiversity in the UK?

    The UK boasts more than 70,000 known species of animals, plants, fungi and microorganisms.

    Read the full answer

  • How do humans affect biodiversity?

    Humanity impacts the planet's biodiversity in multiple ways, both deliberate and accidental.

    Read the full answer

  • How does the growing global population and increasing consumption affect biodiversity?

    Since the middle of the 20th century, the human population has grown dramatically.

    Read the full answer

  • How does climate change affect biodiversity?

    The environmental changes being driven by climate change are disturbing natural habitats and species in ways that are still only becoming clear.

    Read the full answer

  • How does deforestation affect biodiversity?

    Forests contain some of the richest concentrations of biodiversity on the planet. But between 1990 and 2020, around 420 million hectares of mainly tropical forest has been lost.

    Read the full answer

  • What can we do to protect biodiversity?

    Loss of natural habitats has been taking place over thousands of years, but scientists are confident that we have ways to help biodiversity recover.

    Read the full answer

  • What can I do as an individual to protect biodiversity?

    While large scale changes in behaviour, policies and measures will be essential, individuals have a vital part to play.

    Read the full answer

  • Can we allow nature to regenerate without intervention?

    Biodiversity loss is a complex issue involving many overlapping processes. While nature can recover when left to do so, it requires dramatic changes in our behaviour for this to happen.

    Read the full answer

  • How do we decide what is worth saving or putting our efforts into protecting?

    The value of the natural world can be interpreted in many ways, from their raw economic value to the inherent social, cultural and emotional benefits they provide.

    Read the full answer

Was this page useful?
Thank you for your feedback
Thank you for your feedback. Please help us improve this page by taking our short survey.