Nearly one-third of tree species at risk of extinction

Almost one in three tree species could risk extinction as a result of livestock farming, logging and agriculture, a new report has found.

The data assessed how the world’s almost 60,000 tree species are getting on and discovered that 30 per cent of them, or 17,500, are at risk of disappearing completely.

Species particularly at risk include oaks, maple, ebonies and magnolia, according to the report which was published by Botanic Gardens Conservation International (BGCI).

Meanwhile, the Menai whitebeam tree, which has just 30 growing in North Wales, is one of hundreds of tree species which are on the verge of extinction, the first “state of the world’s trees” report cautions.

Overall, one in five tree species are directly used by humans for food, fuel, timber, medicines and horticulture, amongst other things.

However, at least 142 tree species are now recorded as extinct and many are in danger of extinction. This is due to over exploitation and mismanagement, with threats to trees including clearances for livestock farming, growing agricultural crops and logging for timber, according to the assessment.

Climate change is also putting trees at risk of extinction due to loss of suitable habitat as temperatures increase and weather changes. Central America’s cloud forest species are at particular risk due to this.

A further 180 tree species are also being threatened by sea level rise and more severe weather, including magnolias in the Caribbean. Meanwhile, risk of fire has been identified as a major threat to trees in Madagascar and to a US oak species.

In total, 440 tree species are on the brink of extinction, according to the report. This is because they have less than 50 individual trees remaining in the wild. These include trees such as the Menai whitebeam in North Wales and the Mulanje cedar in Malawi.

It appears that islands have the largest proportion of trees under threat. Overall, 69 per cent of trees on the UK Overseas Territory of St Helena are at risk of extinction and 59 per cent of those found in Madagascar are in danger of dying out.

In Europe, 58 per cent of native European trees are at risk of becoming extinct in the wild, with whitebeams and rowan trees at most risk.

Overall, Brazil has the highest number of threatened tree species with mahogany and rosewoods threatened with extinction there due to timber extraction. The same two species are at risk in the Caribbean, while ebony in Madagascar is also at risk due to logging.

In the UK and North America, pests and diseases are causing severe decline to ash tree population numbers while oaks are threatened by deforestation in South and Central America, according to the report.

However, the report is not entirely negative and also highlights hope for conserving trees. It indicated that two-thirds (64 per cent) of all tree species can be found in at least one protected area. Meanwhile, about 30 per cent can be found in collections including botanic gardens and seed banks.

BGCI is calling for governments and experts to extend protected area coverage for threatened tree species and increase funding for the issue. They are also calling for conservation of at-risk trees in botanic gardens and seed banks and are urging the expansion of tree planting schemes to help tackle the problem.

The study grouped together work from the Global Tree Assessment over the last five years, which has seen over 60 institutions and in excess of 500 experts examine the extinction risk for the world’s 58,497 different species of tree.

BGCI secretary general Paul Smith said: “This report is a wake-up call to everyone around the world that trees need help.

“Every tree species matters - to the millions of other species that depend on trees, and to people all over the world.”

He added: “For the first time, thanks to the information provided by the state of the world’s trees report, we can pinpoint exactly which tree species need our help, so policymakers and conservation experts can deploy the resources and expertise needed to prevent future extinctions.”

Jon Paul Rodriguez, chairman of the International Union for Conservation of Nature’s species survival commission, explained: “For the first time, the state of the world’s trees (report) provides a comprehensive breakdown of our world’s trees.

“Knowing where they are and why they are threatened is the first step towards acting for their conservation,” he said.

“Despite the worrying data, I look forward to future state of the world’s trees reports, where I hope to learn of the increase in the number of known species and the decline in the proportion facing high extinction risk, due to the success of premeditated, coordinated global conservation action,” Mr Rodriguez added.