Thirty per cent of the tree species across the world are at risk of extinction and over 440 tree species are on the brink of extinction, according to the latest report by the Botanic Gardens Conservation International (BGCI).
The report, compiling work led by the Global Tree Assessment (GTA), is the culmination of five years of research to identify major gaps in tree conservation efforts. It is one of the first assessments of the world’s threatened trees.
Despite the loss, the BGCI in the report expressed hope for the future with conservation efforts led by botanical community worldwide seen growing. The report said that at least 64 per cent of all tree species could be found in at least one protected area, and about 30 per cent in botanic gardens, seed banks, or other ex situ collections.
BGCI Secretary General Paul Smith informed that the report was a wakeup 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. For the first time, thanks to the information provided by the State of the World’s Tree 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,” Paul Smith said.
Meanwhile, IUCN Species Survival Commission chair Jon Paul Rodriguez opined that the report for the first time gave a comprehensive breakdown of the world’s trees. “Of the 58,497 known species, 30% are threatened and 142 have gone extinct. Knowing where they are and why they are threatened is the first step towards acting for their conservation. Despite the worrying data, I look forward to future State of the World 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,” Jon Paul Rodriguez said.
CLIMATE CHANGE A GROWING THREAT
The report notes that humans directly use one in five tree species for food, fuel, timber, medicines, horticulture and a lot more. Despite the value of trees, many face extinction as a result of over-exploitation and mismanagement. The greatest threats facing trees include habitat loss from agriculture and grazing, followed by over-exploitation from logging and harvesting, the report pointed out.
It stated that one in three trees harvested currently for timber are threatened with extinction.
On Climate change, the report mentioned that many trees risk losing areas of suitable habitat as temperature and weather changed. This affects species in both temperate and tropical habitats, with Cloud Forest tree species of Central America being at particular risk.
It also said that about 180 tree species are directly threatened by sea level rise and severe weather events. This threat is most severe to island species, including magnolias in the Caribbean. An increased occurrence of fire is a major threat to trees in Madagascar, and a major risk to US species of oak and Nothofagus trees in Australia and South America.
COUNTRIES WHERE ACTION IS NEEDED MOST
The report pointed out that 58 per cent of native trees are threatened in Europe. Whitebeams and Rowan (Sorbus genus) are the most threatened species of trees in Europe. Brazil, which has some of the most biodiverse forests in the world, has the highest number of tree species (8,847) and the most threatened tree species (1,788).
However, the report finds that it is island tree species that are more proportionally at risk. This is particularly concerning, because many islands have species of trees that can be found nowhere else.
The BGCI in the report identifies for the first time which threats are having the greatest impact on specific tree species. The main threat to tree species across the world is deforestation for agriculture.
- On Borneo, the expansion of palm oil plantations is a major threat to the Dipterocarpaceae species, one of the most threatened tree groups of trees on the planet. These large tropical trees make up the majority of the lowland habitat on the island, and their decline has led to species such as the Bornean orangutan to become Critically Endangered.
- Species of oaks and Nothofagus are also at risk from habitat loss because of deforestation, particularly in Central (Mexico) and South America (Chile and Argentina), respectively. The countries with the highest number of threatened oak species are Mexico (32 species), China (36), Vietnam (20), and the United States (16).
Logging, and illegal logging in particular, is contributing to the considerable decline of valuable timber trees.
- In Madagascar, timber extraction of ebony and rosewood species is causing widespread habitat loss across the island. The same can be said of mahogany trees and rosewoods across the Caribbean and in Brazil.
- Other major threatened groups of trees include the well known Magnolia and Camellia species, currently under threat from unsustainable plant collection from the wild for commercial use, while pests and diseases are causing severe decline to ash populations in the UK and North America.
Need of Tree conservation
Trees are the backbone of natural ecosystem. They store 50 per cent of the world’s terrestrial carbon and provide a buffer from extreme weather, such hurricanes and tsunamis. They provide habitat and food for millions of other species. The extinction of a single tree species could cause a domino effect, catalysing the loss of many other species.
ROADMAP FOR THE FUTURE
The BGCI hopes to catalyse action among policymakers and conservation experts across the world. Moreover, the BGCI launched a new GlobalTree Portal, an online database tracking conservation efforts for trees at a species, country, and global level. The BGCI recommend five key actions for policymakers and experts in order to protect and bring back threatened species:
- Extend protected area coverage for threatened tree species that are currently not-well represented in protected areas
- Ensure that all globally threatened tree species, where possible, are conserved in botanic garden and seed bank collections
- Increase availability of Government and corporate funding for threatened tree species
- Expand tree planting schemes, and ensure the targeted planting of threatened and native species
- Increase global collaboration to tackle tree extinction, by participating in international efforts such as the Global Conservation Consortia.