Keystone Species Notes Write or draw what’s in red

Review… Which one if more realistic? Which one has more biodiversity?

What is biodiversity? (Write whats in red) Biodiversity: the variety of animal/plant species in a specific area Why is biodiversity important? The more biodiversity an ecosystem has the STRONGER the ecosystem is in response to changes Grasshopper population reduced Frogs and Pythons die off Grass takes over Ecosystem cannot recover and forever changed Food chain

Rats population decreases Results? More grasshoppers Less corn Wolf, python, and eagle eat more of other species In a food web: Ecosystem changes but it can recover if initial population increases back to normal levels (write down)

Draw this picture In this ocean ecosystem & food web, this starfish (Pisaster) is the top predator & is also known as the area’s KEYSTONE species What do you think will happen if Pisaster is removed? Chitons= 8 sectioned, flexible cousins to clams Limpets= Wide shelled water snails Mussel= 2 sections, elliptical clam Barnacles= non-mobile suspension feeders, cousins to crabs & lobsters

What happened? (read only)

Put “x” on the eliminated organisms: Diversity in tide pools is greatly reduced! Barnacles (acorn & goose) & mussels (bivalve Mytilus) take over the entire ecosystem (because they reproduce & grow faster than chitons and limpets) Snails population increases as well X X X

Food chain vs. food web Food chain = weak Food web = strong Food webs have more biodiversity & so are stronger than food chains Biodiversity = a total of all the organisms living in an area The more biodiversity, the stronger the ecosystem -think of how hard it is to remove a spider web if you walk through one!

So what? (write only what is in red) The tide pools have less diversity and I should care why? If another ecological event happened would this ecosystem survive? Likely not- less biodiversity means ecosystem not as strong Entire ecosystem could fall apart Could effect neighboring ecosystems as well Our food web is beginning to look more like a food chain & could easily break! X X X

Keystone species definition: Keystone species= a species on which other species in an ecosystem largely depend on if removed from the ecosystem, the ecosystem would change dramatically and lose biodiversity Without the keystone, a brick bridge is weak & may collapse Just like in ecosystem!

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q Write the following questions onto your notes (LEAVE SPACE BETWEEN EACH for RESPONSE) & answer these from the video: What is a trophic cascade? What National park did this take place in? When were wolves reintroduced in the park? What happened when the elk moved out of the valley and gorges? What do beavers do for the ecosystem? What happened when the wolves killed coyotes? How did the wolves change the behavior of the rivers?

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q What is a trophic cascade? When you remove a top predator or a key organism (i.e. a keystone species) and the rest of ecosystem is effected

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q 2) What National park did this take place in? YELLOWSTONE

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q What is a trophic cascade? What National park did this take place in? When were wolves reintroduced in the park? 1995

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q 4) What happened when the elk moved out of the valley and gorges? Trees & shrubs could grow around the rivers again. This stabilized the river banks & changed the path of the river.

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q 5) What do beavers do for the ecosystem? They created their own aquatic niches- more life in ecosystem! They build dams to slow water flow and allow for more aquatic life

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q 6)What happened when the wolves killed coyotes? More mice and rabbits More hawks! More weasels More foxes More badgers More ravens, eagles, and bears

Wolf Case Study https://www.youtube.com/watch?v=ysa5OBhXz-Q 7) How did the wolves change the behavior of the rivers? Wolves ate deer/elk so elk not near river as often More vegetation/trees More vegetation means stronger riverbed Stronger riverbanks = rivers stronger in areas

Summary: write at bottom of notes 7 sentence summary of notes