Biodiversity under threat homework
What is sustainable yield?
There are two types of sustainable yield; maximum and optimum. Maximum sustainable yield is the maximum of crop that you can harvest from an ecosystem sustainable. Harvesting wildflowers, fish and other animals is part of the indigenous people’s lifestyles and is usually always sustainable. Optimum sustainable yield is the maximum that you can harvest from an ecosystem while still having separate uses for the local people of the area.
Explain how the southern ocean and campfire are examples of sustainable management?
The southern oceans are examples of sustainable management. The southern oceans encircles Antarctica and accounts for around 10% of the world’s oceans. The Antarctic treaty was brought in 1961 due over exploitation of fishing in the Southern Ocean by mostly fleets of soviet trawlers. This unfortunately led to the extinction of several species of fin fish. A model has been put in place to calculate the fishing yield and is one of the most sophisticated models due to its three pronged approach. The first is the single species approach, which sets a limit for harvesting individual species that are indefinitely sustainable. This irradiates the possibility of extinctions. The next approach is the ecosystem approach which involves considering harvested species both on their own and in relation to dependant species and the whole environment. The last is the precautionary principle which aims to model the consequences of allow a further expansion on fishing before it is permitted
Campfire stands for the communal areas management program for indigenous resources and was a pioneering scheme in the late 1980s. Under British colonial rule large sections of the indigenous population were forced to live in communal areas known as tribal trust lands. Campfire aimed at the long term development management and sustainable use of natural resources in each communal area. This was achieved by placing responsibility with local people and allowing local communities the directly benefit from exploitation of the available resources such as wildlife. Because they are bottom up schemes, campfire schemes varied locally with administrative back-up and advice provided by Zimbabwe department of national parks and wildlife management. Details of wildlife species involved and how they were used varied. Many schemes made money from big game hunting at sustainable yield levels. This was controversial as environmentalists did not believe that hunting endangered species was a good way to protect them. The economic collapse of Zimbabwe undermined the scheme. It eventually collapsed due to varying factors such as loss of staff, lack of funding and poaching.