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BIODIVERSITY LOSS
Massive Extinctions From Human Activity
As well as the need for biodiversity for continued ecosystem survival (as explained in the Who Cares? section on this web site), from a human perspective, from common drugs to possible cures for cancers, most of our medicine come from plants, many of which are now endangered.
However, it has long been feared that human activity is causing massive extinctions. The previous link, to a report from Environment New Service (August 2, 1999) says that “The current extinction rate is now approaching 1,000 times the background rate and may climb to 10,000 times the background rate during the next century, if present trends continue. At this rate, one-third to two-thirds of all species of plants, animals, and other organisms would be lost during the second half of the next century, a loss that would easily equal those of past extinctions.”
A huge report known as the Millennium Ecosystem Assessment, started in 2000, was released in March 2005. Amongst many warnings for humankind, it noted that there has been (as summarized from the BBC) a substantial and largely irreversible loss in the diversity of life on Earth, with some 10-30% of the mammal, bird and amphibian species currently threatened with extinction, all due to human actions. (See this site’s section on sustainable development for more on that assessment.)
A huge report known as the Millennium Ecosystem Assessment, started in 2000, was released in March 2005. Amongst many warnings for humankind, it noted that there has been (as summarized from the BBC) a substantial and largely irreversible loss in the diversity of life on Earth, with some 10-30% of the mammal, bird and amphibian species currently threatened with extinction, all due to human actions. (See this site’s section on sustainable development for more on that assessment.)
A report from the World Wide Fund for Nature (WWF) in 2006 confirmed concerns from the previous year, noting that
Already resources are depleting, with the report showing that vertebrate species populations have declined by about one-third in the 33 years from 1970 to 2003. At the same time, humanity’s Ecological Footprint—the demand people place upon the natural world—has increased to the point where the Earth is unable to keep up in the struggle to regenerate.
— Human footprint too big for nature, WWF, October 24, 2006 (Emphasis added)
The International Union for Conservation of Nature (IUCN) notes in a video that:
•1 bird out of 8,
•1 mammal out of 4,
•1 conifer out of 4,
•1 amphibian out of 3, and
•6 marine turtles out of 7, are all threatened with extinction
In addition,
•75% of genetic diversity of agricultural crops has been lost
•75% of the world’s fisheries are fully or over exploited
•Up to 70% of the world’s known species risk extinction if the global temperatures rise by more than 3.5°C
•1/3rd of reef-building corals around the world are threatened with extinction
•Every second a parcel of rainforest the size of a football field disappears
•Over 350 million people suffer from severe water scarcity
The world environmental situation is likely to be further aggravated by the increasingly rapid, large scale global extinction of species. It occurred in the 20th century at a rate that was a thousand times higher than the average rate during the preceding 65 million years. This is likely to destabilize various ecosystems including agricultural systems.
…In a slow extinction, various balancing mechanisms can develop. Noone knows what will be the result of this extremely rapid extinction rate. What is known, for sure, is that the world ecological system has been kept in balance through a very complex and multifaceted interaction between a huge number of species. This rapid extinction is therefore likely to precipitate collapses of ecosystems at a global scale. This is predicted to create large-scale agricultural problems, threatening food supplies to hundreds of millions of people. This ecological prediction does not take into consideration the effects of global warming which will further aggravate the situation
Industrialized fishing has contributed importantly to mass extinction due to repeatedly failed attempts at limiting the fishing
A new global study concludes that 90 percent of all large fishes have disappeared from the world’s oceans in the past half century, the devastating result of industrial fishing. The study, which took 10 years to complete and was published in the international journal Nature, paints a grim picture of the Earth’s current populations of such species as sharks, swordfish, tuna and marlin.
…The loss of predatory fishes is likely to cause multiple complex imbalances in marine ecology.
Another cause for extensive fish extinction is the destruction of coral reefs. This is caused by a combination of causes, including warming of oceans, damage from fishing tools and a harmful infection of coral organisms promoted by ocean pollution. It will take hundreds of thousands of years to restore what is now being destroyed in a few decades.
…According to the most comprehensive study done so far in this field, over a million species will be lost in the coming 50 years. The most important cause was found to be climate change
…NOTE: The above presentation encompasses only the most important and burning global environmental problems. There are several additional ones, especially in the field of chemical pollution that contribute to harm the environment or upset the ecological balance.
— Jaan Suurkula, World-wide cooperation required to prevent global crisis; Part one— the problem, Physicians and Scientists for Responsible Application of Science and Technology, February 6, 2004 [Emphasis is original]
Click to view the laws in protecting wildlife
Terms :
vulnerable species - A species particularly at risk because of low or declining numbers or small range, but not a threatened species.
threatened species – a species whose population is not yet low enough to be in immediate danger of extinction, but who certainly faces serious problems. If the problems affecting these species aren’t resolved, it is probable that the species will become endangered. The eastern indigo snake and the red kangaroo are examples of threatened species.
endangered species – a specie, plant or animal, that is in immediate danger of becoming extinct. Its numbers are usually low, and it needs protection in order to survive. The Siberian tiger, the southern sea otter, the snow leopard, the green pitcher plant, and thousands of other plants and animals are endangered worldwide.
extinct species – an extinct species is one that is no longer living. The passenger pigeon, the dodo, and the Stegosaurus are examples of extinct species. These animals no longer exist on the earth.
© 1997 National Wildlife Federation.
Facts:
- According to scientists, more than one and one-half million species exist on the earth today. However, recent estimates state that at least 20 times that many species inhabit the planet.
- In the United States, 735 species of plants and 496 species of animals are listed as threatened or endangered.
- 266 of these listed species have recovery plans currently under development.
- There are more than 1,000 animal species endangered worldwide.
- There are more than 3,500 protected areas in existence worldwide. These areas include parks, wildlife refuges and other reserves. They cover a total of nearly 2 million square miles (5 million square km), or 3% of our total land area.
- Aquatic species, which are often overlooked, are facing serious trouble. One third of the United States’ fish species, two-thirds of its crayfish species, and almost three-quarters of its mussel species are in trouble.
WHY SAVE THEM?
Plants and animals hold medicinal, agricultural, ecological, commercial and aesthetic/recreational value. Endangered species must be protected and saved so that future generations can experience their presence and value.
Medicinal
Plants and animals are responsible for a variety of useful medications. In fact, about forty percent of all prescriptions written today are composed from the natural compounds of different species. These species not only save lives, but they contribute to a prospering pharmaceutical industry worth over $40 billion annually. Unfortunately, only 5% of known plant species have been screened for their medicinal values, although we continue to lose up to 100 species daily.
The Pacific yew, a slow-growing tree found in the ancient forests of the Pacific Northwest, was historically considered a "trash" tree (it was burned after clearcutting). However, a substance in its bark taxol was recently identified as one of the most promising treatments for ovarian and breast cancer
Additionally, more than 3 million American heart disease sufferers would perish within 72 hours of a heart attack without digitalis, a drug derived from the purple foxglove.
Additionally, more than 3 million American heart disease sufferers would perish within 72 hours of a heart attack without digitalis, a drug derived from the purple foxglove.
Agricultural
There are an estimated 80,000 edible plants in the world. Humans depend upon only 20 species of these plants, such as wheat and corn, to provide 90% of the world's food. Wild relatives of these common crops contain essential disease-resistant material. They also provide humans with the means to develop new crops that can grow in inadequate lands such as in poor soils or drought-stricken areas to help solve the world hunger problem. In the 1970s, genetic material from a wild corn species in Mexico was used to stop a leaf fungus that had previously wiped out 15% of the U.S. corn crop.
There are an estimated 80,000 edible plants in the world. Humans depend upon only 20 species of these plants, such as wheat and corn, to provide 90% of the world's food. Wild relatives of these common crops contain essential disease-resistant material. They also provide humans with the means to develop new crops that can grow in inadequate lands such as in poor soils or drought-stricken areas to help solve the world hunger problem. In the 1970s, genetic material from a wild corn species in Mexico was used to stop a leaf fungus that had previously wiped out 15% of the U.S. corn crop.
Ecological
Plant and animal species are the foundation of healthy ecosystems. Humans depend on ecosystems such as coastal estuaries, prairie grasslands, and ancient forests to purify their air, clean their water, and supply them with food. When species become endangered, it is an indicator that the health of these vital ecosystems is beginning to unravel. The U.S. Fish and Wildlife Service estimates that losing one plant species can trigger the loss of up to 30 other insect, plant and higher animal species.
Commercial
Various wild species are commercially raised, directly contributing to local and regional economies. Commercial and recreational salmon fishing in the Pacific Northwest provides 60,000 jobs and $1 billion annually in personal income, and is the center of Pacific Northwest Native American culture. This industry and way of life, however, is in trouble as salmon decline due to habitat degradation from dams, clearcutting, and overgrazing along streams.
Various wild species are commercially raised, directly contributing to local and regional economies. Commercial and recreational salmon fishing in the Pacific Northwest provides 60,000 jobs and $1 billion annually in personal income, and is the center of Pacific Northwest Native American culture. This industry and way of life, however, is in trouble as salmon decline due to habitat degradation from dams, clearcutting, and overgrazing along streams.
Freshwater mussels which are harvested, cut into beads, and used to stimulate pearl construction in oysters form the basis of a thriving industry which supports approximately 10,000 U.S. jobs and contributes over $700 million to the U.S. economy annually. Unfortunately, 43% of the freshwater mussel species in North America are currently endangered or extinct.
Aesthetic/Recreational
Source of Information: The National Wildlife Federation’s Endangered Species Program
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