From Plant Press, Vol. 1, No. 3, May 1998.
One out of eight plant species worldwide is at risk of extinction, according to the most comprehensive scientific assessment ever assembled on the status of the world’s plants. This announcement was made on April 8 at a press conference at the Smithsonian’s National Museum of Natural History as the 1997 IUCN Red List of Threatened Plants was released. The IUCN Red List reveals that 12.5%, or 34,000, of the world’s vascular plant species are threatened. In the United States, perhaps one of the most thoroughly studied countries in the world, 29% of the nation’s 16,000 plant species are at risk of extinction.
The Red List is the result of a 20-year effort by a unique coalition of scientists, conservation organizations, botanical gardens and museums. The Red List was published by IUCN-The World Conservation Union and compiled by the World Conservation Monitoring Centre (WCMC). Conservation assessments were provided by numerous scientists and conservationists with major input from the Smithsonian’s Department of Botany, The Nature Conservancy, Environment Australia and CSIRO, the National Botanical Institute (South Africa), Royal Botanic Gardens at Kew and Edinburgh, and the New York Botanical Garden.
The Department of Botany has had a collaborative agreement with IUCN and WCMC since 1980 to gather information on threatened plants and habitats in Mexico, Central and South America. Through the efforts of Jane Villa-Lobos, Director of the Latin American Plants Program, an extensive global network of scientists was established to assemble and monitor vital information on the conservation status of plants in this diverse region. Staff in the department and the plant collections in the U.S. National Herbarium were an invaluable source of information on taxonomy, distribution and conservation status. This scientific data is a major component of the Red List.
Of the estimated 270,000 known species of vascular plants, which include ferns, fern allies, gymnosperms (including conifers and cycads), and flowering plants, 33,798 were found to be at risk of extinction. These plants are found in 369 families and are scattered throughout 200 countries. Of the plant species named in the Red List, 91% are found only in a single country. A limited geographic distribution can make a species much more vulnerable and may reduce options for its protection. In addition, islands or island groups, which often have high rates of endemicity, face particularly high levels of threat to their flora. Seven out of the top ten areas listed according to percentage of threatened flora are islands: St. Helena, Mauritius, Seychelles, Jamaica, French Polynesia, Pitcairn, and Reunion.
A great number of plant species known to have medicinal value are at risk of disappearing, leaving their healing potential unfulfilled. For instance, 75% of the species from the yew family, a source of important cancer-fighting compounds, are threatened. The willow family, from which aspirin is derived, has 12% of its species threatened. Numerous other species whose medicinal value has not yet been studied also are at risk.
The Red List shows that 380 species have become extinct in the wild, with an additional 371 species listed as Extinct/Endangered. Over 6,500 species are categorized as Endangered, indicating their numbers have been drastically reduced to a critical level and they are deemed to be in immediate danger of extinction. Threat assessments are assigned according to the pre-1994 IUCN threat categories. The introduction to the book details the purpose and history of the project, an explanation of the information and an analysis of the list, including valuable tables on threatened plants in each country by IUCN category and by major taxa and families.
Publication of the IUCN Red List of Threatened Plants marks a turning point for conservation. The book, an important new conservation tool, provides baseline information to measure conservation progress and serves as a primary source of data on plant species. Most importantly, it provides the building blocks on which to base worldwide efforts to conserve plant species and the ecosystems they inhabit.