• the important physical factors that make a habitat suitable for a particular species
• the need to take into account behavioural factors when designing an artificial habitat
• methods of intervention to prevent the extinction of endangered species
• how a population’s size can be affected by:
  • the absence of natural predators
  • the introduction of predators from outside the habitat
  • habitat destruction
  • competition with similar species
  • disease

After viewing the programme and doing relevant follow-up work, pupils should be able to:

• describe how temperature, wind, humidity and light are important features of a habitat
• describe how vegetation, water and the surface of the ground can be important to animals
• explain how keeping animals in captivity can protect endangered species
• explain how predators can keep plant growth under control
• give an example of how a plant might grow out of control when moved to a different habitat
• describe how the escape of American mink and the destruction of river banks have caused a fall in the number of water voles
• describe how microchips can be used to monitor a population of animals
• explain why grey squirrels out-compete red squirrels in most habitats
• explain why the parapox vaccine has made the decline in red squirrel numbers more dramatic
• describe how squirrels can be monitored without having to be seen