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Kew and the fight against extinction

Kew is helping fight extinction. But how do we know what species to fight for? By determining how threatened species are and adding them to the world’s Red List.
Date: 
7 November 2018
Blog team: 
Author: 
Lucy Greenfield

Plants on the edge

Imagine living in a world where a plant you saw yesterday is no longer around today. We are living in that world. 

The St Helena olive is now extinct. Native to the island of St Helena in the South Atlantic Ocean, exploitation of the island’s resources has driven this plant to extinction. To stop this happening to other species, we need to identify what needs saving. 

The International Union for Conservation of Nature’s Red List of Threatened Species (IUCN Red List) is an assessment of the conservation status of plants, animals and fungi across the globe.
 
Since the IUCN Red List began in 1964, it has assessed over 93,000 species. But considering this is just over 5% of documented species on the planet there is still a way to go. By 2020, the IUCN aims to have assessed 160,000 species. And Kew is helping...
 


The St Helena olive (Nesiota elliptica) was native to St Helena island. It is now extinct because of the exploitation of the island's resources. IUCN Red List category: Extinct


Kew's involvement with the IUCN

Our dedicated team of scientists and volunteers makes up Kew’s Plant Assessment Unit. The team uses Kew’s expertise and Collections to support the assessment of species for the Red List. This work benefits from Toyota funding, which is being channelled to Kew through Toyota Motor Corporation's five-year partnership with the IUCN to develop the Red List of Threatened Species. 

Plant collections held in Kew’s Herbarium tell us where a plant was located at a specific time. We can then use scientific expertise and tools like Google Earth, as well as having scientists return to the site itself, to determine the extinction risk faced by that species today. 
  
Once assessed, species are given a category based on their likelihood of extinction from Least Concern (no or very little risk of extinction) to Critically Endangered (very close to extinction ).

Like the St Helena olive, some species are no longer likely to become extinct, they are Extinct. However some still survive within botanical gardens such as the yellow fatu which is growing at Kew. These species are categorised as Extinct in the Wild. 

The IUCN Red List aims to assess all species, but the main focus has been on species already thought to be threatened. Overall, Kew has found that one in five plant species are threatened with extinction. 
 


The last wild yellow fatu (Abutilon pitcairnense) was destroyed by a landslide in 2005. Luckily, cuttings and seeds had been collected from the plant and it grows at botanical gardens including Kew. IUCN Red List category: Extinct in the Wild


The Temperate House Red List

Kew’s Temperate House is home to an invaluable collection of temperate zone plants. Many of these plants have been categorised as threatened on the IUCN Red List. 

Amongst these species is the rat aloe

Although it is one of the few poisonous aloes, in small doses it can be used as a laxative. Unfortunately, the rat aloe is categorised as Endangered because it is being threatened by land clearance. 

Another species is the false banana.

A cousin of the banana we eat every day, the false banana is not used for its fruit but for other parts of the plant. Pulp from the leaf is used for flour and the underground stem is boiled like a potato. A family of five is said to be able to live off just 15 plants for a whole year. Fortunately, it is categorised as Least Concern.
 
Visit the Temperate House to learn more about these species and other species in Kew’s temperate collection.
 


The rat aloe (Aloe ballyi) named due to the stink that comes from its broken leaves. It is one of the few poisonous aloes but threatened by land clearance. IUCN Red List category: Endangered


The wider use: conservation of species

The IUCN Red List, despite its name, is more than just a list. 

The information collected during the assessment of a species is vital for the conservation of that species and helps guide effective conservation strategies. 

Users of the information range from governments to conservation organisations like the World Wildlife Fund (WWF). The research supports the development and implementation of international agreements such as the Convention on International Trade in Endangered Species (CITES). 
 
Every 10 years, species should be reassessed to check whether their status has changed. The re-assessment of species provides information to IUCN Red List users on how conservation actions and policies are working. The IUCN Red List is a dynamic resource that is regularly updated with new species and re-assessments. It is a situation report on what is surviving today, to guide us to ensure it is surviving tomorrow. 
 


The false banana (Ensete ventricosum) is not cultivated for its fruit like its Asian cousin, the banana, but for its vegetative parts. It is reported that 15 plants can feed five people for a year. IUCN Red List category: Least Concern




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