The Changes in Red and Grey Squirrels' Population Over Time
Problem: How does the competition between native and invasive squirrels affect population size?
Research:
Red Squirrels
Grey Squirrels:
Hypothesis: The population of the red squirrels will decrease when the invasive more fit grey squirrels are introduced into the ecosystem over time.
Experiment: Finished
The Data Table:
Research:
Red Squirrels
- They have a mass of 250 grams to 340 grams
- The red squirrels bodies' length is from 19 cm to 23 cm
Grey Squirrels:
- Their bodies' length is from 23 cm to 30 cm
- The grey squirrels have a mass of 400 to 600 grams
Hypothesis: The population of the red squirrels will decrease when the invasive more fit grey squirrels are introduced into the ecosystem over time.
Experiment: Finished
The Data Table:
Graph
Conclusion Questions:
1. It was easiest for the red squirrels to find resources before the gray squirrels came. Also, when they had a easier time when there is a low amount of predators and lots of resources. It is the hardest for the red squirrels to find resources when there were many grey squirrels to compete with.
2. The organisms compete for the same resources when there are not enough resources for all of the population to live on. Also, the grey and red squirrels compete for the same resources when the resources are limited.
3. Resources are affected negatively by competition because it is more animals fighting over them. The more squirrels fighting over the resources, the less resources there are.
4. The native squirrels niche would need to change so that they will survive. They could find another source of energy to eat, or they could migrate somewhere else where there is no gray squirrels. Also, over time they could become faster and stronger than the red squirrels but that would take many years.
Claim. Evidence. Reason.
Claim: The red squirrels' population will decrease when the more fit grey squirrels invade their environment.
Evidence: The red squirrels population averaged around 125 squirrels the first 7 years. The next 4 years (the 8th through 11 year) the red squirrels averaged around 79 squirrels, while the grey squirrels averaged around 18 squirrels. The next 4 years ( the 12th through 15 year) the red squirrels averaged around 35 squirrels; the grey squirrels averaged around 117 squirrels. Then, the red squirrels averaged around 6 squirrels in the 16th, 17th, 18th, 19th, and 20th year while the grey squirrels averaged around 173 squirrels. For the last year, the red squirrels were extinct while the grey squirrels had 178 squirrels. The coyotes averaged around 37 coyotes the first 8 years; then, they averaged around 17 coyotes the next 8 years (years 8-15 years). The last 5 years, the coyotes averaged around 13 coyotes.
Reasoning: The red squirrels' population and the grey squirrels' population were affected when they had to compete for resources. The red squirrels' population slowly decreased when they had to fight for resources against the grey squirrels, this shows that the grey squirrels are more fit to survive in that environment than the red squirrels. The data shows that because on the 20th year, there were zero red squirrels and 178 grey squirrels. The predators had a easier time killing/eating the red squirrels because the data shows that there were the highest amount of coyotes the first 8 years when there were only red squirrels. Once the grey squirrels were entered into the environment and they started competing for the same resources as the red squirrels, the coyotes started declining because the easier prey (the red squirrels) to eat were slowly dying out.
1. It was easiest for the red squirrels to find resources before the gray squirrels came. Also, when they had a easier time when there is a low amount of predators and lots of resources. It is the hardest for the red squirrels to find resources when there were many grey squirrels to compete with.
2. The organisms compete for the same resources when there are not enough resources for all of the population to live on. Also, the grey and red squirrels compete for the same resources when the resources are limited.
3. Resources are affected negatively by competition because it is more animals fighting over them. The more squirrels fighting over the resources, the less resources there are.
4. The native squirrels niche would need to change so that they will survive. They could find another source of energy to eat, or they could migrate somewhere else where there is no gray squirrels. Also, over time they could become faster and stronger than the red squirrels but that would take many years.
Claim. Evidence. Reason.
Claim: The red squirrels' population will decrease when the more fit grey squirrels invade their environment.
Evidence: The red squirrels population averaged around 125 squirrels the first 7 years. The next 4 years (the 8th through 11 year) the red squirrels averaged around 79 squirrels, while the grey squirrels averaged around 18 squirrels. The next 4 years ( the 12th through 15 year) the red squirrels averaged around 35 squirrels; the grey squirrels averaged around 117 squirrels. Then, the red squirrels averaged around 6 squirrels in the 16th, 17th, 18th, 19th, and 20th year while the grey squirrels averaged around 173 squirrels. For the last year, the red squirrels were extinct while the grey squirrels had 178 squirrels. The coyotes averaged around 37 coyotes the first 8 years; then, they averaged around 17 coyotes the next 8 years (years 8-15 years). The last 5 years, the coyotes averaged around 13 coyotes.
Reasoning: The red squirrels' population and the grey squirrels' population were affected when they had to compete for resources. The red squirrels' population slowly decreased when they had to fight for resources against the grey squirrels, this shows that the grey squirrels are more fit to survive in that environment than the red squirrels. The data shows that because on the 20th year, there were zero red squirrels and 178 grey squirrels. The predators had a easier time killing/eating the red squirrels because the data shows that there were the highest amount of coyotes the first 8 years when there were only red squirrels. Once the grey squirrels were entered into the environment and they started competing for the same resources as the red squirrels, the coyotes started declining because the easier prey (the red squirrels) to eat were slowly dying out.