Maintaining biodiversity, locally and globally, has many benefits. A varied range of species keeps food chains and ecosystems stable. Plants and animals provide food and materials, and may contain chemicals that can be developed into new medicines. Wild relatives of crops carry genes that could help breed new varieties. Many people also value wildlife for its own sake.
Ecotourism is tourism that brings money to local people while protecting wildlife. Visitors pay to see animals in their natural habitat, so local people have an economic reason to protect them rather than hunt them or clear the land. Too many tourists can still damage the habitat, so numbers must be managed.
Conservation is challenging. Schemes cost a lot of money, and the money may be needed for other things. Conservation can conflict with farming and development, because land used for a reserve cannot be used for crops or housing. Many species, such as migrating birds, cross national borders, so protecting them needs international agreements. These are hard to reach because countries have different priorities and different amounts of money.
Monitoring is difficult too. Reserves can be very large, so checking that species are recovering takes time and people, and illegal hunting is hard to detect and stop. A scheme that is not monitored or enforced may fail.