1. Roles in Ecosystems
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2. Habitat
A habitat is the place an organism lives.

3. Ecological Niche
The ecological niche is an organism’s “job” in an ecosystem.
It includes:
its place in the food web
where it lives
the time of day it is active

4. Ecological Niche
Each organism in an ecosystem usually has a different niche.
This helps to reduce the amount of competition for habitat and resources (like food, water, etc.).

5. Do they have the same niche?

6. Do they have the same niche?
Red-tailed hawk
- eats mice
- hunts in fields
- hunts during the day

7. Do they have the same niche?
2) Eastern screech owl
- eats mice
- hunts in forests
- hunts at night

8. Biodiversity
Biodiversity is the variety of life in a particular ecosystem; also known as biological diversity
Since organisms within an ecosystem have different niches, it allows for greater diversity

9. Native vs. Introduced Species
A native species is a species that has lived in an ecosystem for a long time.
An introduced species is a species that is new to an ecosystem.
Introduced species can arrive naturally (animals move, seeds carried by wind) or by humans.

10. Impact of Introduced Species
Introduced species usually cause problems in an ecosystem.
They compete for a niche with the native species.

11. Example - Starling
Sixty European starlings were released in North America in honour of Shakespeare.
There are now 200 million of them!

12. Example – Cane Toad
Cane toads were introduced into Australia to control insects.

13. Example – Cane Toad They did not really help with the insects.
Now they are causing a
lot of problems.
They are poisonous, so anything that eats them dies.
They are HUGE – and will eat anything they can swallow including many native species.

14. Example – Rabbits Rabbits were brought to Australia by people.
People brought rabbits to Australia.

15. Example – Rabbits
When the rabbits multiplied, they tried many ways to stop them:
- fences
- viruses
- fleas
Nothing
has worked!

16. Make sure you know these words!
Vocabulary
Make sure you know these words!
Habitat
Ecological niche
Competition
Native species
Introduced species
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