The major causes of wildlife extinction are as follow:
1. Degradation of ecosystem
There are different types of living beings in the terrestrial and aquatic ecosystems. Cattle, insects, plants, trees, etc. grow in the terrestrial ecosystem while fish, some insects, small plants live in the aquatic ecosystem. The terrestrial ecosystem is degraded due to forest fire, destruction of forests, use of insecticides and pesticides, etc. An aquatic ecosystem is spoilt by falling stones and soil when construction work is done and by explosions. Thus, the living beings on both land and water are affected. Because of the degraded ecosystem, there will be the lack of habitat for the living beings. So, human beings should not degrade the ecosystem. We should not discharge harmful things like rubbish, insecticides, etc. directly to water sources. When we protect the ecosystem, it helps to protect the biodiversity.
2. Loss of habitat
Habitat plays a significant role in retaining biodiversity. Natural habitat is ruined because of human activities like construction work, the extension of agricultural work, destruction of forests, etc. which results in bad effects in animal’s habitat, food cycle, climate and reproduction progress. The numerical growth of living beings and their life cycle are hampered. It is unwise to destroy the natural habitat while conducting development construction and human activities. The habitat which has been destroyed should be restored.
3. Loss of mobility
The deterioration of the natural environment causes the loss of mobility of birds and animals. The causes of deterioration of the environment are the destruction of the forest, expansion of agricultural land and urbanization. All these factors limit space for the animals and birds for roaming. That’s why the natural habitat for the several animals and birds have been diminished. In this situation, they have to stay within a limited area. So, people should not ruin the natural environment if they want to conserve animals and birds. We should try to make the dry and uncultivated land suitable for the habitat of animals and birds.
4. Limitation of expansion of vegetation
Land for cultivation is extended due to the population growth. Various types of development and construction work are continuing. Similarly, settlement areas are expanding and urbanization is taking place. Grazing land is declining in size. These activities harm the forest, vegetation, herbs, etc. Because of these adverse effects, biodiversity is degrading. People should grow trees in the surrounding of their houses, either side of the road and bare fields. Pasture lands should not be damaged. Grass should be grown in the bare place for the cattle. Thus, the greenery can be increased.
5. International trade
The trade of some items of wild origin such as animals fur, bones, tusks, musk or as orchids, medicinal plants resulted in the decline of wild animals and plants. Maximum use of items such as decorative souvenirs, perfumes, cosmetics etc. in the developed countries has increased the loss of wild animals and plants in many countries.
The methods of conservation of wildlife are as follow:
National parks, wildlife reserves, and conservation area have been established as protected areas in different parts of Nepal. There are total 10 national parks, 3 wildlife reserves, 4 conservation areas, 1 hunting reserve and 11 buffer zones. The wildlife reserves, conservation areas, and national parks are helping in a conservation of the living beings in in-situ, that is, in their original places. The living beings get the proper natural environment, food and habitat there. Chitwan National Park, Langtang National Park, Parsa Wildlife Reserve, Annapurna Conservation Area, Dhorpatan Hunting Reserve, etc. are some examples.
The artificial environment (ex-situ conservation) should be created for the conservation of rare living beings as in-situ conservation is not possible for all types of living beings. In order to conserve the disappearing and rare animals, birds, and vegetation, the government has established a botanical garden, parks, and zoos. Attempts are being made to create a suitable environment in the central zoo to conserve animals and birds. Similarly, botanical gardens are preserving different types of vegetation. These activities contribute to the conservation of biodiversity through protecting the genes of the living beings and assisting them to grow and reproduce.
Government and non-governmental organizations are involved in biodiversity conservation. They create awareness of its forest and Soil Conservation Ministry has been conducting natural environment and watershed conservation programme. Similarly, Ministry of Environment, Science and Technology formulates the policy on environmental conservation and implements it. It coordinates the programmes contributing to the conservation of ecosystem and biodiversity. Biodiversity is a common property. So, its conservation is the duty of all. Joint efforts can help to achieve the success. Conservation programme should be conducted at community levels. National Trust for Nature Conservation (NTNC) conducts programmes at local level whereas international organizations such as IUCN- The World Conservation Union, World Wildlife Fund (WWF) are also involved in conservation programmes. These programmes help in the conservation of biodiversity and environment as well.