1. Watch the Wolves of Yellowstone | EARTH A New Wild (https://vimeo.com/116273819) video clip from the beginning and stop at 2:36 minutes. As you are watching, create a bubble map below that includes all of the things that happened in the Yellowstone ecosystem in the absence of wolves. Add as many lines and bubbles from the center bubble as needed.
2. Using your bubble maps as a guide, create a food chain of the three organisms that are involved in a trophic cascade in Yellowstone National Park.
Wolves eat the elk
Elk eat plant
Plants get eaten
3. With the elimination of wolves from the ecosystem, how was the population of plants (producers) indirectly affected?
The population of plants was reduced because of the overgrazing of plants by elk. Overgrazing occurred because the elk population was no longer controlled or checked by the wolves.
4. Predict what would happen to the wolf and elk populations if there was a drought that caused many of the plant species to dry up and/or die.
The elk population would decrease because its food source is decreased. This would also cause the wolf population to decrease because they would have less food.
5. You have already identified that wolves Wolf Population are a predator of elk. Describe the general trend of the elk and wolf populations between 1993 and 2003.
In 1994 the population of elk increased slightly and was just under 20,000 individuals. However, from that point on the general trend was population decrease. By 2003 the number of elk was just below 10,000 individuals. During the same period, the wolf population trend was to increase. The wolf population rose from 0 to 100 during that period.
6. Based on the graphs, what year do you think wolves were introduced to Yellowstone? Explain why you think this.
The wolves were introduced in 1995. The wolf population in 1994 was zero and in 1995 the count was around 20 individuals.
7. Using information from the...