One in three tree species at risk of extinction: Report October 28, 2024

Several species of eucalyptus are at risk of extinction.

By AFP - Agence France Presse

One in three tree species at risk of extinction: Report

By Mariëtte Le Roux

More than one in three tree species are at risk of extinction worldwide, threatening life as we know it on Earth, according to a report published on Monday.

The warning was made in the Global Tree Assessment, contained in an update of the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species.

Published to coincide with the UN COP16 biodiversity summit, held in the Colombian city of Cali, the report states that more than 16,000 tree species are at risk of extinction.

More than 47,000 species were assessed for the study out of an estimated 58,000 species believed to exist in the world.

Trees are felled for timber and to clear land for agriculture and human expansion. Climate change poses an additional threat through worsening droughts and forest fires.

The numbers are not merely symbolic.

People “depend on tree species for food, wood, fuel (and) medicines,” expert Emily Beech told AFP.

They also produce the oxygen we breathe and absorb carbon dioxide emissions from the atmosphere, which trap heat.

“Trees are essential to sustaining life on Earth through their vital role in ecosystems, and millions of people depend on them for their lives and livelihoods,” said IUCN Director General Grethel Aguilar.

A 2015 study estimated that there are around three trillion individual trees in the world.

The study, published in the scientific journal Nature, estimated that more than 15 billion trees are cut down every year, and the global number of trees has almost halved since the beginning of human civilization.

More than 5,000 of the species on the IUCN Red List are used for construction timber, and more than 2,000 species for medicines, food, and fuel.

Species at risk include the horse chestnut and the ginkgo, both used for medical applications, the large-leaved mahogany used in furniture making, as well as several species of ash, magnolia, and eucalyptus, said Beech, head of conservation prioritization at Botanic Gardens Conservation International (BGCI), which contributed to the assessment of the trees.

According to the IUCN report, the number of trees at risk is “more than double the number of all threatened birds, mammals, reptiles and amphibians combined.”

Tree species are at risk of extinction in 192 countries, but the highest proportion is found on islands due to rapid urban development and the expansion of agriculture, as well as the introduction of invasive species, pests, and diseases from elsewhere.

In South America, which has the greatest diversity of trees in the world, 3,356 of the 13,668 species assessed are at risk of extinction.

Many species on the continent, which is home to the Amazon jungle, have probably not even been discovered yet.

When they are discovered, they are “more likely to be threatened with extinction,” said the report.

The report calls for the protection and restoration of the forest through tree planting, as well as the conservation of endangered species through seed banks and botanical garden collections.

More than 1,000 experts contributed to the assessment.

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