Warmup 9-15-16 What can biodiversity indicate about an ecosystem? (reference page 67 notebook)

Macroinvertebrates

Notebook page 72 – tape in Learning Target: I can connect my learning about biodiversity to a local stream ecosystem and explore ways that biodiversity can be used as a measure of health of an ecosystem.

What clues can you investigate in order to determine whether an ecosystem is healthy or unhealthy? Biodiversity or #/types of organisms in an ecosystem? Are there enough abiotic resources to support biotic organisms?

Is a stream an ecosystem? Explain. Yes – it has both biotic (living) and abiotic (non-living) components.

How can you assess the health of a stream? Look at the area around the stream to see what substances might be entering it Checking to see if plants are growing around the stream Checking for erosion around the stream Checking the color of the water to see if it “looks polluted” Check to see what organisms live in the stream

What kinds of stressors might affect the stream? Runoff from factories, farms, neighborhoods. Other pollution Erosion/sedimentation Introduction of non-native species Reduction of native species.

Do all organisms react to stressors the same way Do all organisms react to stressors the same way? What is an example from the biodiversity reading on Chesapeake bay? No – some organisms are more tolerant to change or stressors than others. Salamanders – in the Chesapeake Bay, they could not withstand changes and their population decreased.

What is a macroinvertebrate? An invertebrate (no backbone) that can be seen at the macro level (no microscope). Found in streams lik: Floyd’s Fork Harrod’s Creek Beargrass Creek

Video clip https://www.youtube.com/watch?v=v_Dnf4gJo8E

Macroinvertebrates in local streams CADDISFLY LARVA MAYFLY LARVA STONEFLY LARVA DRAGONFLY LARVA DAMSELFLY LARVA MIDGE LARVA RAT-TAILED MAGGOT

What is a macroinvertebrate? Exit slip 9-15-16 What is a macroinvertebrate?

Graphic organizer page 69

Game Today we are going to play a game that simulates the changes that happen in a stream when an environmental stressor, such as a pollutant, is introduced. 2 students will represent environmental stressors

Caddisfly larva Must hop with both feet together, stopping every 5 hops to catch their breath.

Stonefly larva Must do a push-up every 10 steps.

Mayfly larva Must flap arms and spin in circles when crossing the field.

Damselfly and dragonfly larve Must only walk (no running)

Midge and Rat-tailed maggot No hindrance – you can run

To survive You must reach the finish line without being tagged. It is easiest to catch those with a hindrance. This mirrors real life – species that lack the ability to adapt to changes tend to die and disappear from an environment. If you get tagged, you go to the sideline. You stay there until the end of the round. Then flip your tag around. This shows the death of an organism and an increase in a tolerant species. The round ends when all the macroinvertebrates are either tagged (on the sideline) or have reached the finish line. We will then record the number of species in the table. We will then complete two more rounds.

What will happen to the macroinvertebrates if their ecosystem were damaged or polluted? It would depend, some organisms would tolerate it better than others.

Which of the organisms would tolerate pollution well? All under the tolerant category. Rat-tailed maggot Midge Larva

If you were conducting a stream study and noted a large, consistent population of stonefly and mayfly larva, what could you infer about the stream? It must not contain many pollutants and must be a relatively healthy environment since both are sensitive. If it were very polluted then they wouldn’t be able to survive in the environment.

On the other hand, if you conducted a stream study and found no stonefly or mayfly larva, but found mostly midge larva and rat-tailed maggots, what would that tell you about the stream? Indicator that the stream is polluted or damaged since those organisms are tolerant and the sensitive organisms are no longer able to survive.

Predict what would happen if even more environmental stressors were introduced into the stream. Fewer sensitive macroinvertebrates would survive each round until there were only tolerant species left in the stream.

What would happen if the situation improved and there were fewer stressors in the stream? More tolerant species would survive and the biodiversity of the stream would increase.

Students will…. Apply the context of biodiversity to a local stream ecosystem and explore factors that influence its health.

Previous knowledge You have been introduced to the idea of biodiversity as an indicator of the overall health of an ecosystem. Today you will simulate a stream ecosystem in order to draw conclusions about its biodiversity.