Interactions in Ecosystems

Birth of an Ecosystem

Surtsey Island, Icelandhttp://www.youtube.com/watch?v=4MmX_i7S9u4

Ecosystem InteractionsCompetition:

Is the interaction between two or more organisms competing for the same resource in a habitat.

Competition can happen between the same species. Example:Male mountain goat competing for the right to mate.

Competition can happen between different species. Example:Raccoons and ravens can both feed on eggs from the same bird’s nest.

Predation

Ecosystem Interactions

Occurs when one organism eats another organism to obtain food.

What are some examples of the methods animals use to avoid predation?

Chameleon – colour change to blend with surroundings

Porcupine – throws needles

Deer – can usually outrun a bear

Types of Symbiosis

Mutualism

Commensalism

Parasitism

Mutualism

• In Mutualism both species benefit from the symbiotic partnership.

Commensalism

• Commensalism occurs when one species benefits from a relationship and the other organism is neither harmed nor does it benefit in any way.

Parasitism

• Parasitism occurs when one species benefits at the expense of another species. Parasites live on or inside the host and obtain some or all of the nutrition from the host.

Identify the type of Symbiotic Relationship.

Commensalism

ParasitismMutualism

Ecosystem’s Carrying Capacity

As a population grows, each individual gets a smaller share of the resources in the area.

After a while, there are fewer births and more deaths. Eventually, the number of births equals the number of deaths.

equilibrium is number of deaths in a population equal to the number of births.

When this happens, the habitat is said to have reached its carrying capacity.

Carrying capacity is the maximum number of individuals that an ecosystem can support.

Limiting FactorsIs an environmental factor that prevents an increase in the number of organisms in a

population.

Examples of Abiotic

Limiting Factors:

Amounts of:• sunlight• water• soil• air• storms

Examples of Biotic

Limiting Factors:

• competition among organisms for resources• presence of predators• presence of disease-causing organisms.

Sustainable Ecosystem