G4: Conservation and Biodiversity

1. G4: Conservation and Biodiversity

2. Explain the use of biotic indices and indicator species in monitoring environmental change. • Indicator species: highly sensitive to environmental changes; populations increase or decrease significantly depending on changes in the environment. • They are good indicators of change. • Frog populations are very vulnerable to pollution, • Sludge worms are good indicators of low oxygen concentration in waterways. • Biotic indices are calculated via the number of tolerant and intolerant species at a time.

3. Outline the factors that contributed to the extinction of one named animal species. • Examples could include the Carolina parakeet, dodo, passenger pigeon and thylacine (Tasmanian wolf).

4. Outline the biogeographical features of nature reserves that promote the conservation of diversity. • Large nature reserves usually promote conservation of biodiversity more effectively than small ones. • The ecology of the edges of ecosystems is different from the central areas due to edge effects. An example of an edge effect is the egg-laying habits of the cowbird of the western United States. It feeds in open areas, but it lays its eggs in the nests of other birds near the edges of forests. Fragmentation of forests has led to a considerable increase in cowbird populations because of the increase in forest edge. • Wildlife corridors allow organisms to move between different parts of a fragmented habitat, for example, tunnels under busy roads.

5. Discuss the role of active management techniques in conservation. • Whale Conservation • Rainforest Conservation • Bald Eagle Conservation • Wolf Conservation

6. Discuss the advantages of in situ conservation of endangered species (terrestrial and aquatic nature reserves). • Homework: Part 1

7. Outline the use of ex situ conservation measures, including captive breeding of animals, botanic gardens and seed banks • Homework Part 2