Starter: Name as many predator/prey relationships as possible – can they be linked into a food web? Extension – choose only one environment

Title: Predator/Prey relationshipsLO: To evaluate the effect of predator and prey numbers on food webs

What will win: Shark or Albatross? http://www.youtube.com/watch?v=10u9Wg

ZGSwk

The shark wins!

Predator/Prey relationships

Adaptations

Shark Albatross

How is the shark adapted to catch prey?

Sharp teeth Fast movement Huge mouth Forward facing eyes to

see long distances Good sense of smell

How is the albatross adapted to avoid being caught?

Huge wings to fly Good eyesight Eyes at side of head

to see prey Good sense of hearing

Predator or prey?• Look at the following animals. Write down whether each

one is a predator or prey.• Write down two adaptations that it has for either catching

prey or avoiding being eaten.

Predator/Prey I need volunteers to act as predators.

Lets investigate what happens when we eat all the prey!

What has happened? Explain what will happen to prey and

predator numbers if tiger sharks eat a large number of albatross◦ This can be drawn on a simple graph

If we prey numbers decrease, because predators eat them all, then a short time afterwards predator numbers will decrease too as there is not enough food.

As predator numbers decrease (and predators hunt different food), prey numbers get a chance to increase again.

This means predators again have more food and their numbers can increase

Predator/Prey relationships

Predator/Prey graphAnalyse the relationship between the number of predator and prey on this graph.

What do you notice about this graph?

Analysing predator/prey graphs

Look at the Wolves (predator) and Moose (prey) number graph. Describe what you notice.

At which year is the predator number the highest? At which year are the prey numbers the highest?◦ Explain why you think this is so.

How can predators be used to control a prey population? Why would you want to do that?

Suggest what else may cause predator/prey numbers to fall in a population?

answers.

What would happen if the grass died? What would happen if the population of slugs decreased?What would happen if the population of insects decreased?

Predator Prey cycle Draw a flow diagram showing what happens

to predator and prey numbers if predators catch a large number of prey

One evening, a lion found a hare eating some grass. He was very pleased and was just about to eat the hare when he noticed some deer nearby. Forgetting the hare, he jumped up and chased after the deer, making so much noise that the hare finally noticed him and ran away. After a long chase, the lion realised that he could not catch the deer. Remembering the hare, he returned to where it had been eating, only to find that, like the deer, it had run away. ‘If I hadn’t

left the hare in the hope of getting something bigger,’ he said, ‘I could have had a meal’.

The lion and the hare

Which animal or animals in the fable are predators? Prey?

What adaptation did the deer have to protect themselves from being eaten?

The phrases below describe adaptations of predators and prey. Write the word ‘predator’ or the word ‘prey’ to show which adaptation each has.◦ An animal with forward-facing eyes.◦ An animal that is very shy and nervous.◦ An animal with eyes on the sides of its head◦ An animal that has large, sharp claws.

What lesson do you think the fable is trying to teach us?

.……I am a word which means an animal that does not have a back bone.…….I am a word which means all the living and non-living things around me e.g., the amount of rain and predators.…….I am a word which means all of a species have died out because they cannot survive in a habitat.…….I am a vertebrate with smooth slimy skin.…….I am a word which means a warm blooded animal which produces milk to feed its young.…….I am an example of an invertebrate.…….I am a word which means to arrange into groups of things that are similar

Extinct

Vertebrate

Environment

Population

Amphibian

Adaptation

Classification

Habitat

Invertebrate

Mammal

Community

Insect

What Am I……?