WILD & FARMED SALMON POPULATIONSGENERATI

ON WILD POP. SIZE WILD STATUS FARMED POP SIZE FARMED STATUS

1 10,000 at carrying capacity 1,500 substantial profit23456789

1011121314151617181920

WILD & FARMED SALMON POPULATIONSGENERATI

ON WILD POP. SIZE WILD STATUS FARMED POP SIZE FARMED STATUS

1 10,000 at carrying capacity 1,500 substantial profit23456789

1011121314151617181920

CHANGES DUE TO POPULATION GROWTH

Your group will track two salmon populations, one wild & one farmed. Here is some background information to get you started:

Salmon farm is an open-net system set up in the coastal waters of the Eastern US (map below)

Wild salmon’s migration routes bring them in close contact with salmon farms.

Using the tables below, you will be collecting data for 20 generations and determining their status.

WILD SALMON POPULATION# of fish ≤ 5,000 5,001 – 7,000 7,001 – 9,000 9,001 –

12,000Population

statusCritically

overfishedMarginally overfished Stable At carrying

capacityFARMED SALMON POPULATION

# of fish ≤ 800 801 – 1,100 1,101 – 1,300 ≥ 1,301Population Negative No profit Moderate Substantial

status profit (loss) (break even) profit profitCHANGES DUE TO POPULATION GROWTHPROCEDURE:

1. Begin your simulation by rolling a number on the die at your table. Use the key below to determine what happens to your population:

# ROLLED SITUATION ENVIRONMENTAL IMPACT

WILD POP. EFFECT

FARMED POP. EFFECT

1 Farmed salmon escape.

Escapes interbreed & compete for resources with wild population.

Loss of 500 salmon due to lack of resources & reduced fitness because of interbreeding.

No change in population size.

2 Disease at salmon farm

Disease spreads to wild population.

Loss of 1,500 salmon from disease.

Loss of 250 salmon from disease.

3Antibiotics given to farmed salmon to prevent disease.

Kills “good” bacteria that the ecosystem needs to function.

Ecosystem disrupted. Causes loss of 750 salmon.

Disease decreases. Population increases by 250 salmon.

4Decrease in density of salmon in pens.

Milder environmental impact.

Improved habitat causes increase of 500 salmon.

Fewer salmon per pen, loss of 350 salmon.

5

If farm has over 1,400 salmon, waste accumulates under pens.

Wastewater in local ecosystem causes habitat & food loss.

Reduction of available resources causes loss of 1,000 salmon.

Decrease in water quality causes loss of 500 salmon.

6If farm has over 1,400 salmon, new pen is built.

Takes up the space of wild salmon habitat.

Decrease of resources causes loss of 500 salmon.

New pen houses more salmon. Increase by 350 salmon.

2. Add or subtract from the salmon populations as directed from the table above. Record your data in your science notebook. Repeat until all 20 generations have been completed.

* note: if you roll a 5 or 6 and your population is NOT 1,400 or greater, keep rolling until you get a 1 – 4. *

3. When you are finished, conduct a line graph that shows the population curves for BOTH the wild and farmed salmon in your notebook.