Protecting 1.2 Percent of Earth’s Land Could Prevent Extinctions

Humanity is ‘mutilating’ the tree of life, cutting away entire branches one after another at a rate of destruction the Earth has never previously endured.

Yet there is still reason for hope.

At the end of 2022, the United Nations unveiled a landmark ‘peace pact with nature’ to prevent plants and animals being lost in the present mass extinction. Under the agreement, countries committed to designating 30 percent of the planet as protected areas by 2030.

The world remains a long way from meeting that target. However, a hopeful new study suggests that, during the crucial years ahead, attention should shift away from the sheer size of nature reserves and towards the amount of life they support.

Conservation Imperatives for rare and endangered biodiversity

Scientists from more than 20 organisations around the world have concluded that leaving only 1.2 percent of the Earth’s land undisturbed could “head off” the most probable and imminent extinctions.

“Most species on Earth are rare, meaning that species either have very narrow ranges or they occur at very low densities or both,” explains lead author Eric Dinerstein, a conservation biologist at Resolve, a non-governmental organisation working on sustainable solutions to environmental challenges.

“And rarity is very concentrated.”

That is fortunate, as it suggests targeted conservation action could achieve several objectives at once.

However, Dinerstein and his colleagues warn that the chance to act is rapidly closing, while current conservation work is not as strategically targeted as it could be.

Using published worldwide biodiversity data, the international research team - comprising scientists from the US, the UK, China, Saudi Arabia, India, Brazil, Indonesia and numerous other countries - estimated where the planet’s most threatened species live.

They pinpointed more than 16,000 unprotected sites on land. Although this may sound substantial, the areas together account for just 1.2 percent of the Earth’s terrestrial surface.

Half lie in the tropics, and many are close to existing nature reserves.

To make conservation as practical and affordable as possible, Dinerstein and his co-authors say these areas should receive the greatest focus. They propose classifying them as ‘Conservation Imperatives’.

Protected land is missing the highest-priority habitats

From 2018 to 2023, countries collectively protected 1.2 million square kilometres of land. Yet the new assessment found that these refuges encompass only 7 percent of “irreplaceable sites harboring rare and endangered biodiversity”.

“Efforts and investments to address the climate crisis have overshadowed the attention governments and intergovernmental processes have paid to the biodiversity crisis,” argue Dinerstein and colleagues.

This is a significant failing that has hindered conservation. Habitat loss now affects roughly 88 percent of all threatened species.

Of the land newly designated for protection between 2018 and 2023, merely 2.4 percent was tropical or subtropical forest. The researchers identified these environments as containing the greatest number of Conservation Imperatives.

In comparison, almost 70 percent of recently protected areas covered temperate broadleaf and mixed forests, habitats that do not hold large numbers of Conservation Imperatives.

The cost of safeguarding the remaining wilderness

“Our analysis estimated that protecting the Conservation Imperatives in the tropics would cost approximately $34 billion per year over the next five years,” says co-author Andy Lee, an environmental scientist at Resolve.

“This represents less than 0.2 percent of the United States' GDP, less than 9 percent of the annual subsidies benefiting the global fossil fuel industry, and a fraction of the revenue generated from the mining and agroforestry industries each year.”

Restoring damaged habitats would now take too long to rescue many of the planet’s most endangered species. Protecting the wilderness that is still left is therefore essential.

By relatively stringent estimates, just about 2.8 percent of the Earth’s land ecosystems remain entirely intact, dispersed across the globe.

Only 11 percent of those places were within protected areas in 2021. That appears to be a sensible starting point.

The study was published in Frontiers in Science.