Key Idea: Most marks in topic 3.3 come from reserve design and conservation choices. At HL, also learn who makes conservation succeed, rewilding limits, measuring success and ecotourism.
1. Reserve design (most marks)
- Large reserves hold more species and bigger populations than small ones.
- A round shape has less edge, so fewer edge effects reach the core.
- Corridors link reserves, so animals can move and breed between them.
- A buffer zone around the core keeps farms, roads and towns at a distance.
2. Species or habitat?
- Species-based (ex situ): zoos, captive breeding, seed banks.
- Habitat-based (in situ): protect the whole ecosystem, so many species are saved at once.
- A flagship species attracts money; a keystone species holds the ecosystem together.
- A mixed approach protects the habitat and gives extra help to one species.
3. Values and HL ideas
- Why preserve: aesthetic, ecological, economic, ethical and social reasons.
- Different values lead to different choices, such as protecting wild land or using it for jobs.
- At HL: who drives success (IGOs, governments, NGOs), rewilding limits, measuring success and ecotourism.
- Success is measured by population trends and changes in IUCN status.
How it is examined:
| Question | How to score |
|---|---|
| [1] to [2] Identify a design feature from a map | Name the feature and say what it does. |
| [2] to [4] Explain how a reserve's design helps | Size, shape, edge, corridors, buffer zone: one point each. |
| [2] Distinguish flagship and keystone species | One line for each, with an example. |
| [4] to [7] Explain habitat or species-based strategies | Name the strategy, then its effect, with an example. |
| [9] Discuss a conservation choice | Values on both sides, named examples, then a judgement. |
Key terms, one line each:
| Term | In one line |
|---|---|
| In situ / ex situ | in the natural habitat / away from it, such as a zoo or seed bank |
| Edge effect | changes near the border of a habitat, such as more light, wind and predators |
| Flagship / keystone species | raises support / holds the ecosystem together |
| NGO | a non-governmental organization, such as WWF |
| Rewilding | restoring an area so natural processes run it again |
| Ecotourism | nature tourism that pays for conservation and supports local people |
Last-minute check: answer, then tap to see.
Name one NGO and what it does for conservation. WWF: raises money, runs projects and lobbies governments.
How do you measure whether conservation worked? Population trends over time and a better IUCN status.
Give one limitation of rewilding. Conflict with farmers, such as livestock killed by predators.
How can ecotourism help conservation? Visitors pay, so local people earn more from living wildlife.
Why is a round reserve better than a long thin one? Less edge, so fewer edge effects reach the core.
Since 2001, the Knepp Estate in southern England has turned farmland back into wild land, with free-roaming cattle, ponies and pigs. Discuss the benefits and limitations of rewilding.
Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
Exam tips
- For a reserve map, name the feature and say what it does for the species.
- Say whether a strategy is species-based or habitat-based, with a named example.
- In a discuss, give both sides, then a judgement.
- For success, quote a number: a population trend or a change in IUCN status.