Population Simulation

Jackrabbits & Coyotes

BellworkUse the macroinvertebrate data table to answer the following Qs:1. What is the water quality SCORE and ASSESSMENT?2. Would you swim in this water? Explain why or why not.3. Would adding POUCH SNAILS to the water make the water LESS healthy

than it is now….explain why or why not? 4. If the population of dobsonflies suddenly decreased, but the mayflies &

stoneflies stayed the same, what could that mean?

3

12

3

9

1

2

1

1

24

Excellent

Aquatic Macroinvertebrates react differently

• They still exist in healthy streams! Healthy streams have everything (high diversity)!

• But beware of LARGE populations of these…

Midges

Tubifex Worms

Pouch Snails

1. What is the relationship between the Roadrunner & Wile E. Coyote?

2. Describe another real life example of this kind of relationship.

Predator-Prey Relationship

Jackrabbits & Coyotes• How do you think the size of a predator population

and prey population affect one another?

• Write a hypothesis (if…then…as measured by…)

Procedures- in lab notebook• Spread out 3 rabbits (white) evenly across habitat (green sheet)• Hold 1 coyote (red) 1ft above lab table, & drop it once to eat. Must

land on/touch a rabbit to eat it. – 0 rabbits eaten= coyote dies; 1 rabbit eaten= coyote survives;

3+ rabbits eaten=coyote reproduces (add one coyote for ea. 3 eaten)– Surviving rabbits double (reproduce) every generation

• Record & calculate info @ end of each gen• Count out start #s for next gen & repeat for 18+ gensIf all coyotes die: 1 new coyote immigrates inIf all rabbits die: 3 new rabbits immigrate in

Example

3 1 0 3 3 1 0 06 1 2 4 4 0 1 0

How many rabbits must a coyote eat in one drop to reproduce?

Jobs• Jefe- Mathematician today (makes sure everything is

counted & added correctly)- see me if you get to 200+ rabbits

• Recorder- double checks jefe’s math before starting each round, makes sure everyone records info correctly

• Materials- makes sure materials respected, put away, in charge of spreading out rabbits evenly as possible

• Presenter- Measures drop distances each round, makes sure no one moves coyotes until all eaten rabbits counted & removed

Run your experiment!

Half-way Closure

• What kinds of things are LIMITS to how big your jackrabbit or coyote population can grow?

Update your Ecology Divider

Ecology Unit1. Notes

2. Labs

3. Assignments

4. Tests

-What is Life Notetaker-Energy Flow Notes-Trophic Levels & Rule of 10 Notes-Biome Research Notes-Biome Poster Notes-Aquatic Macroinvertebrates & Water Quality-Population Notes

-Cricket Mark & Recapture Lab-Aquatic Macroinvertebrates Lab

-What Is Life Quiz

Population Notes (after break)

Limiting FactorsWhat kinds of factors LIMIT how big the jackrabbit & coyote populations can grow?

Limiting FactorsLimiting Factors = factors that limit the growth

of a population: food, water, shelter, & space

Carrying Capacity AnalogyBucket = habitat/resources

Water = new births

Overflow = deaths due to exceeding the carrying capacity

Carrying CapacityCarrying capacity (K) = # of individuals that

the environment can supportOvershoot

Estimate the carrying capacity of hares ~40-60

Estimate the carrying capacity of lynx ~20-30

Graph & Conclusion

• Graph how the population of jackrabbits vs coyotes change over time (think about what kind of graph this is…)

• Conclusion paragraph- in lab notebook under procedures (complete sentences, separate paper)

1. Which line do you think represents the prey population? Explain why you chose it.

2. Which line do you think represents the predator population? Explain why you chose it.

3. Estimate the carrying capacity of the prey population.4. In what year did the prey population overshoot the carrying

capacity the most?5. What does this mean about the limiting factors that year?

ClosureDo on blank BWspot

Predator-Prey Population Graph

1. Which line do you think represents the prey population? Explain why you chose it.

2. Which line do you think represents the predator population? Explain why you chose it.

3. Estimate the carrying capacity of the prey population.4. In what year did the prey population overshoot the carrying

capacity the most?5. What does this mean about the limiting factors that year?

Closure Predator-Prey Population Graph

Green line, b/c bigger population

Red, b/c smaller population

40 to 60

1865

There must have been lots of grass (or whatever prey feeds on), water, space, etc.

Sponge: Think about it…Hunting permits are frequently issued to help control certain

populations of animals.

1. When would a state want to issue a LOT of permits for deer hunting?

2. How could this affect the wolf population in the area?3. Are deers autotrophs or heterotrophs? What about wolves?

Explain your answers.