160 likes | 392 Views
Roles in Ecosystems. Habitat. A habitat is the place an organism lives. 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. Ecological Niche.
E N D
Habitat • A habitat is the place an organism lives.
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
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.).
Do they have the same niche? • Red-tailed hawk • - eats mice • - hunts in fields • - hunts during the day
Do they have the same niche? • 2) Eastern screech owl • - eats mice • - hunts in forests • - hunts at night
Native vs. Introduced Species • A native species is a species (type of living thing) 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.
Impact of Introduced Species • Introduced species usually cause problems in an ecosystem. • They compete for a niche with the native species.
Example - Starling • Sixty European starlings were released in North America in honour of Shakespeare. • There are now 200 million of them!
Example – Cane Toad • Cane toads were introduced into Australia to control insects.
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.
Example – Rabbits • Rabbits were brought to Australia by people. People brought rabbits to Australia.
Example – Rabbits • When the rabbits multiplied, they tried many ways to stop them: - fences - viruses - fleas • Nothing has worked!
Vocabulary Make sure you know these words! • Habitat • Ecological niche • Competition • Native species • Introduced species