Biodiversity is the variety of life forms we see around us mammals, birds, reptiles, amphibians, fish, insects and other invertebrates, plants, fungi, and micro-organisms such as protists, bacteria and viruses.
Biodiversity is a resource. Maintaining a wide variety of species is significant because our practical needs and values for the future are unpredictable. We have learnt a vast amount from the study of other species, yet we are allowing many to disappear without any knowledge of their existence. It makes sense to preserve as many species and genetic stocks as possible, given that as yet we do not know which are potentially useful as food sources, medicines and materials. Genes express different characteristics and the gene pool is diminishing. Biodiversity is our insurance for the future. Losses are irreversible.
Species are disappearing at rates never witnessed before on Earth. Of the 50 million species believed to inhabit the Earth, only approximately 1.5 million species have been identified. Over the past 25 years, one quarter of life on the planet has been extinguished, and another one third may be extinct by 2025. One species per hour is forced into extinction, and the rate appears to be increasing. The rate at which species are becoming extinct is between 100 to 1000 times more rapid than it was prior to the existence of humankind, and most of this increase is due to human activity.
Species loss is primarily due to the destruction of habitats, especially wetlands and tropical forest. Excessive hunting, over-collection and pollution and poisoning by pesticides are also contributing factors. The effects of climate change from greenhouse gases, and UV radiation increase from ozone layer damage, may further accelerate the process of species loss.
Some species of animals and plants are threatened by hunting, poaching and illegal trade. The market in illegal trade of wildlife and wildlife products is around US $100,000 per year. At the turn of the twentieth century there were about 100,000 tigers in Asia, and at this time there are only approximately 5,000 tigers left. The Caspian, Balinese and Javan tigers have become extinct in the last 60 years, and the five remaining sub-species that remain are highly endangered.
The tiger's habitat is being cleared for agriculture, cattle ranching, logging and housing. Tiger parts are greatly desired in East Asia, and poaching is big business. Tigers are a protected species, and trade in tiger products is illegal. Yet the business is so lucrative that for some it is worth the risk of jail or death. Tiger bone and other parts are used in oriental medicines. Tourists and wealthy people overseas buy tiger souvenirs.
The African elephant population decreased by 50% over approximately 20 years, primarily as a result of poaching for the ivory trade. In 1970, there were almost two million African elephants, but by 1989 there were only 600,000. Currently the population is between 302,000 and 487,000. However, while the number of elephants is decreasing, in some areas of Africa they are being culled (killed) by the park authorities who are meant to protect them. Elephants are large animals, and inflict a lot of damage to their habitat. They uproot trees and trample on vegetation. An increase in human population numbers has drastically reduced the elephant's habitat during the last century, and the density of elephants is so high in Southern Africa that culling is considered necessary to protect the habitat for other animals, and to keep a balanced ecosystem. The solution is to increase the habitat for all wildlife, including the elephant.
There are approximately 40,000 wild Asian elephants. There are also many working domestic elephants in Asia. The wild elephants in Asia are under threat, as forests are cleared for agriculture. Losing their habitat is the main problem.
Bears throughout the world are losing their habitat. Many are domesticated, and frequently mistreated and exploited to entertain humans. Foxhunting, bullfighting and cockfighting are problems in some parts of the world.
The use of ocean drift nets up to 30 miles in length has resulted in gross damage to marine life, such as turtles and dolphins.
The waters of the North-East Atlantic were for centuries one of the most productive fishing areas in the world. Over-fishing and pollution have depleted stocks to such critical levels that the effect is being felt all along the food chain. In January 1994, 75,000 dead seabirds were washed up on the shores of North East Britain. The emaciated birds had starved to death. Fishermen in Scotland have blamed seals for eating all the fish. Although natural factors contribute in shifting ecological balance, they are insignificant compared with human pressures. Pollution and demand are the major causes for the decline of fish.
Tropical forest covers 7% of the Earth’s surface, but contains over 90% of species. Prior to their extensive alteration by humans, 1600 million hectares of tropical forest existed. By the mid 1970’s, this was 1000 million hectares. At a current clearing rate of 2% per year, this means that all rainforests could vanish in 30 to 50 years. 30% of all species including almost 50% of all flowering plants, will be lost if we cut down the rainforests. This includes several hundred vertebrates, hundreds of thousands of plants, and over one million species of insects.
Our understanding of ecosystems is so insufficient that we cannot be certain of the impact if any single component is removed. With greater diversity, this enables life to adapt more effectively to changing conditions. It enhances its resilience to cope with ecological stresses.
No organism lives in isolation from other living things, and each has its own way of life which contributes to the balance of nature. The inter-dependence and successful functioning of all these parts is a key factor to the healthiness of the planet as a whole.
Genetic diversity is imperative for the cultivation of domestic species. It enabled early man to develop crops and livestock which were a pre-requisite of settled agriculture, and which now enable breeders to develop new varieties. A shift towards intensive farming has resulted in many species of domestic farm animals and plants becoming extinct. As multi-nationals buy up the seeds of domestic plants and withdraw them from the marketplace. Biodiversity is reduced and this is crucial for a healthy ecosystem. A limited range of breeds of domestic animals and plants are more vulnerable to disease and agricultural failure. Rare breeds shaped by humans are part of a global gene pool. Once a breed or species becomes extinct, its unique genetic characteristics are lost forever. It is important to preserve the widest possible range for future farming use.
A diversity of species and habitats must be conserved because they are part of our cultural heritage. They are beautiful and enrich our lives. The culture of a nation is closely allied to its landscape and wildlife. We must pass an environment to the next generation no less abundant than the one that we inherited.
Inadequate management and the weakness of laws have resulted in an alarming rate of damage to the habitat of the world's wildlife. Greater understanding of relationships between living things is important. Improved monitoring is required.
What you can do
Learn more about endangered flora and fauna.
Support zoos engaged in conservation programs, and which breed endangered species and release them into the wild.
Do not buy products from endangered species.
Plant more trees and shrubs in your local community.
While travelling, be aware of our intrusion into the world of native species and try avoiding damaging them or their habitat.
Get involved with direct action to save habitats. Keep a watch over natural sites.
Support conservation groups like Information for Action or World Wide Fund for Nature (WWF) with donations.
Write a letter or email your Government representative, urge him or her to take action to protect endangered species and their habitats, and to set up a monitoring system to ensure protection.
Write a letter or email to the editor of your local newspaper; urge him or her to publish your concerns about local endangered species and their habitats.
Consume grains, meat and other products from rare domestic species. If there is consumer demand, more people will farm rare breeds. Ask your local retailer to stock meat and other products from rare breeds.