Trophic Levels – is the position an organism occupies in a food chain. It refers to food or feeding

Trophic Levels – is the position an organism occupies in a food chain. It refers to food or feeding.

• Trophic Levels – is the position an organism occupies in a food chain. It refers to food or feeding.

The energy flow from one trophic level to the other is know as a food chain

• The energy flow from one trophic level to the other is know as a food chain

• Producers are at the first ENERGY LEVEL

• Primary Consumers are the SECOND ENERGY LEVEL

• Secondary consumers are at the THIRD ENERGY LEVEL

• Food webs are multiple food chains.

Food webs show ALTERNATIVE PATHWAYS other possible pathways through which an organism can obtain energy

• Food webs show ALTERNATIVE PATHWAYS other possible pathways through which an organism can obtain energy

• Energy lost from chain “link” to “link” is significant!

• from grass to sheep, loss is about 90%!

Each level above only gets 10% of the energy from below

• Each level above only gets 10% of the energy from below

• Ex: 10,000 J of producers (plants) only give 10% of energy to primary consumers
• 1,000 J to primary consumers (snails, minnows, dragonflies)
• 100 J to secondary consumers (small fish)
• 10 J to tertiary consumers (big fish)
• 1 J to quaternary consumers (fish hawk)

Usually no more than 5 trophic levels since 6th level would have very little energy to keep it alive

• Usually no more than 5 trophic levels since 6th level would have very little energy to keep it alive