The Salmon Shadow Food Chain Tower Activity
Students will conduct a simulation to demonstrate control of several variables in the ecosystem, where different scenarios will be used to demonstrate the positive and negative effects humans have on local ecosystems.
This game demonstrates the relationship between trophic levels of the food chain in British Columbia. Trophic levels are connected by predator-prey relationships; in a food chain everything is connected. If one level is disrupted by humans or other influences, the other levels will also be affected as well. Once too many levels are negatively impacted, the whole ecosystem will collapse.
What You Need
- Salmon Jenga Tower - with blocks painted orange (3), blue (11), red (17) and green (23)
- Deck of playing cards
Guide:
- Salmon Sustainability Guide (activity instructions and playing cards at the end)
PowerPoint:
What To Do
Assemble the Jenga tower as follows:
- Place three green blocks side by side. Place three more green blocks on top, perpendicular to the first layer. Continue to stack green blocks for a total of seven layers of green blocks - representing primary producers (algae)
- Repeat with the red blocks (five layers) - representing Pacific salmon
- Repeat with blue blocks (three layers) - representing predators (sea lions and orcas)
- Repeat with orange blocks (one layer) - representing humans
- There will be six extra blocks (two of each red, blue and green blocks)
Directions
- Describe the Pacific salmon food chain using the PowerPoint presentation [slides 6 and 26].
- Have students take turns pulling a card from the deck. The student will complete the task on the card and put the card in a separate pile. Remove blocks are paces to the side of the tower.
- When the tower falls, this represents an ecosystem collapse.
Discovery
A tiny change in the ocean has the potential to disrupt the energy flow within an ecosystem. This can make the food chain unbalanced and make conditions worse for other members of the food chain. For example, a disruption that limits the growth of zooplankton can cause a reduction in salmon populations, or cause salmon to overeat another food source, taking it away from another member of the food chain. This creates a ripple effect throughout the food web.
Respecting the environment can help the entire ecosystem. By ensuring that salmon have clean water/habitat, access to spawning rivers, plenty of food, reducing greenhouse gas emissions and by practising sustainable fishing, we stabilize the food web. This ensures that there is enough food for animal and humans, and protects the fishing industry from economic hardship.
Protecting salmon populations is important in honoring and preserving Indigenous culture and spiritual beliefs.
Salmon Sustainability Guide (activity instructions and playing cards at the end)
What's Happening?
A tiny change in the ocean has the potential to disrupt the energy flow within an ecosystem. This can make the food chain unbalanced and make conditions worse for other members of the food chain. For example, a disruption that limits the growth of zooplankton can cause a reduction in salmon populations, or cause salmon to overeat another food source, taking it away from another member of the food chain. This creates a ripple effect throughout the food web.
Why Does It Matter?
Respecting the environment can help the entire ecosystem. By ensuring that salmon have clean water/habitat, access to spawning rivers, plenty of food, reducing greenhouse gas emissions and by practising sustainable fishing, we stabilize the food web. This ensures that there is enough food for animal and humans, and protects the fishing industry from economic hardship.
Protecting salmon populations is important in honoring and preserving Indigenous culture and spiritual beliefs.
Resources
Salmon Sustainability Guide (activity instructions and playing cards at the end)
