Rapid Rise in Global Extinction Rates – Protect the ESA

The current extinction rate is estimated to be up to a thousand times higher than prehistory rates (Leakey and Lewin 1995, Stearns and Stearns 1999).  This phenomenon has been described as the sixth wave of extinctions by scientists Richard Leakey and Roger Lewin – ecosystems are being disrupted around the world, and the wondrous tapestry of living things that supports human existence is unraveling.

Since 1500, approximately 375 species of invertebrates, 81 species of fish (Hilton-Taylor 2000) and 291 species of mammals, birds, reptiles and amphibians (see Appendix) have become extinct.  About three-fourths of vertebrates other than fish have disappeared since 1800, while only 80 species died out in the previous three centuries.  These figures represent a minimum number.  An estimated 5 million species of animals and plants exist in tropical rainforests, a conservative figure that may apply to insects alone, according to biologist Edward O. Wilson (1988).  About half of these species are restricted or localized in distribution (Wilson 1988).  With this in mind, at the present rate of destruction of tropical forests, some 17,500 species are being lost per year – a rate 1,000 to 10,000 times greater than extinction rates prior to human intervention (Wilson 1988).  

Human activity lies at the root of this potentially catastrophic phenomenon.  Killing for food or sport, as well as conditions created by humans, such as habitat destruction and competition, predation and disease from introduced animals, is responsible for the vast majority of these extinctions.  It is with this perspective that we can see the present situation as an unnatural event, not linked to climatic changes, meteors or volcanic eruptions, but a result of human-caused changes wrought in the Earth’s environments and by direct extermination.

Plant extinctions have accelerated in the past few centuries.  An estimated 5,050 taxa of plants, including species, varieties and other taxonomic groups, have become extinct worldwide since 1700, according to Ghillean T. Prance of the Royal Botanical Gardens Kew (Prance 1990).  This implies at least 17 plants have been lost per year since 1700.  Yet however high this rate appears to be, it is probably a low estimate.  A 1998 study by botanists Kerry S. Walter and Harriet J. Gillett for the International Union for the Conservation of Nature (IUCN) found that 380 species, a number that does not include varieties and other taxa, have recently become extinct.  These authors admit their extinction total may be low as a result of lack of data, and they did not define the time period covered.  

The data lacks exact numbers of plant extinctions.  Plants rarely leave signs of their existence as vertebrates do, since bones are the basis of much data on animal extinctions.  Non-woody plants, which make up the majority of plants, leave little trace when they die, and are soon consumed by microbes.  This is especially true in tropical areas, where plant matter is consumed very quickly.  We know of ancient plants by chance events, such as the preservation of pollen grains or other plant parts in peat, mud, amber or fossilized stone.  When numbers of plant extinctions are estimated, the diversity and status of habitat are important considerations.  Moreover, only a small percentage of all plants have been scientifically described. What is known is a great many regions of the Earth that once had very diverse endemic plants have been destroyed within the past few centuries, and a majority was not thoroughly assessed.

There’s been much wailing and gnashing of teeth in the environmental community since Rep. Richard Pombo (R-Calif.) pushed his overhaul of the Endangered Species Act through the House of Representatives last week. All eyes are now on the Senate to see whether Pombo’s bill — described as “so toxic it’s radioactive” by Jamie Rappaport Clark, who oversaw implementation of the ESA during the Clinton administration — will make it through that august body and onto the desk of President Bush, who’s indicated his support.

Despite assumptions that the Senate — the more deliberative, and generally more eco-friendly, chamber of Congress — would block an initiative so controversial, enviros worry that Pombo is harrowingly close to getting his way. “I can’t remember a time when any major environmental statute was under greater threat,” said John Kostyack, senior counsel at the National Wildlife Federation.

Pombo, a former rancher who once famously (and fraudulently) claimed that his family farm was hobbled financially because it was designated as critical habitat for the endangered kit fox, has been trying to dismantle the ESA for more than 12 years. His bill is designed to wipe out the critical-habitat protections esteemed by many conservationists, thereby making it impossible for the government to prohibit harmful projects on lands deemed necessary to the recovery of imperiled species.

Pombo’s bill would:

– Eliminate critical habitat. That is area now required to be designated when a species is listed and is protected from adverse actions by federal agencies. Instead, “recovery plans” for species, including designation of habitat, would have to be developed within two years. The recovery plans would not have regulatory force and the habitat would not be protected from federal actions.

– Specify that landowners with development plans are due answers from the interior secretary within 180 days, with a 180-day extension possible, about whether the development would harm protected species. If the government fails to respond in time, the development could go forward. If the government blocks the development, the landowner would be paid the fair market value of the proposed development.

– Give the interior secretary the job of determining what constitutes appropriate scientific data for decision-making under the law.