In the big picture, all types of species are lost. Extinction comes to mammals, birds, amphibians, insects, fungi and, of course, plants. Totting up the loss of plant species is difficult. There are an estimated 380,000 plant species – orders of magnitude more than most other forms of life. It’s quite likely that some plant species vanish before they’re even discovered. How to go about monitoring the causes and dimensions of plant species loss?

It’s called the Sampled Red List Index for Plants. In a massive joint effort of the Royal Botanic Gardens (Kew, UK), the Natural History Museum (London, UK), and the International Union for the Conservation of Nature (IUCN) a list of 7,000 species, a random representative sampling from the full list of plant species was used to build a research baseline. The resulting report, the work of hundreds of scientists and volunteers over a period of years and aggregating data from worldwide sources, is the first of its kind. It provides an analysis of the condition of plant species today, and the baseline for comparison in future studies.

The “Red List” is the convention used by the IUCN to highlight those species most endangered. In the case of plants, it does not mean all 7,000 species are at risk. However, the actual figures are disturbing: 1 in 5 (22%) of plant species are currently in danger of becoming extinct. Is this normal? Probably not:

The Royal Botanic Gardens, Kew’s Director, Professor Stephen Hopper, says: “This study confirms what we already suspected, that plants are under threat and the main cause is human induced habitat loss.

“For the first time we have a clear global picture of extinction risk to the world’s known plants. This report shows the most urgent threats and the most threatened regions. In order to answer crucial questions like how fast are we losing species and why, and what we can do about it, we need to establish a baseline so that we have something against which to measure change. The Sampled Red List Index for Plants does exactly that by assessing a large sample of plant species that are collectively representative of all the world’s plants.”

[Source: EurekAlert]

A few factoids from the report are worth a mental notation:

Plants are about as threatened as animals, more threatened than birds, but less threatened than amphibians or corals.
Gymnosperms – conifers (pine trees) and cycads (palm-like) – are the most threatened group of species.
The most threatened species are found in the tropics, where the habitat is also the most threatened.
About a third of the species on the list are not known well enough to assess their risk.

The Sampled Red List Index of Plants, issued September 29, 2010, was delivered in hopes of affecting international opinion and government action. In particular, it is intended to be used for the tenth Conference of the Parties to the Convention on Biological Diversity (October, Nagoya, Japan).

Will the relatively definitive specification of species loss for plants have an impact?

Species loss doesn’t get the notoriety of climate change (though there are relationships). In fact, species loss often doesn’t get much notice at all. There have been successful efforts to dramatize the plight of individual animals (particularly the apes and certain photogenic species), but the involvement of ‘public opinion’ has often been less than even the lip-service of government officials.

Unfortunately, there are many possible reasons for the desuetude:

Species loss is gradual. Much of it will occur unseen and undocumented. The results are years in the future, and human beings have difficulty reacting to a future more than a few months ahead. The results could be dire, but we don’t know that for sure. In fact, the case for the negative impact of species loss is a complex discussion of ecology, economy, and culture – it’s hard to follow. There are plenty of counter examples, cases where a species was declared officially extinct, only it wasn’t. People often have a naïve faith that through science and technology, the species of the Earth will be preserved. (Most have seen the movie Jurassic Park, no?)

I could go on, but it’s a depressing déjà-vu scenario. The shortest summation I can think of is: If it isn’t happening to me, right now, I don’t care.

The dreary pessimist would say: “Oh yes, we’re all part of the great web of life! Only most of us don’t know it, and wouldn’t care if we did.”

And so forth…

There are other ways to look at it. Specifically, look up the special Kew Gardens web site: Plants at Risk It’s informative, interactive, and activist – in a nicely modulated British way.