Population Growth/Decline http://jersey.uoregon.edu/vlab/ExponentialGrowth/ The growth of a population is controlled by several factors, most notably, availability of food, availability of shelter, & hazards/predators that might cause premature death. In this applet, we are going to look at how human population growth can affect the population of another species; in this case, the salmon. Before we begin, let’s discuss a few things: 1. What do human populations need to survive? 2. What resources do human populations consume? 3. If humans consume a resource at a more rapid rate than the resource can be replenished, what happens? The Story of Salmonville The growing community of Salmonville depends on hydroelectric power as their sole source of energy. In other words, they use dams to create 100% of the electricity they need to power their homes, run their machines, create their products, and cook their food. In addition, numerous members of this community own fish restaurants in which salmon is the main course. Salmon is a favorite food of many of the community members. • Salmon is a main source of food for the community, so as the community population grows, more salmon are fished for and eaten. • Hydroelectric power (dams) kill fish. Not all fish of course, but more than would die normally due to natural predators and conditions. • The more people Salmonville has in their community, the more dams they need for power Your task is to create five different scenarios for populations, dams, and fish population. You will record your data in the table on the next page. IMPORTANT: Leave Fish Fill Factor at 10 and Dam Modifier at 1 for this first activity. Activity 1: Create five different scenarios by manipulating population growth rate and technology factor. Record years before fish population disappears. Be reasonable in your settings! For instance DO NOT set population growth at higher than 15%, do not set the Technology Factor higher than 2 (you can use 1.1, 1.2, etc) Scenario Population Growth % Technology Factor Years Before Fish Are Gone 1 2 3 4 5 Activity 2: Run the scenarios you created above again, this time recording the effect every 10 years. You will need data to construct a graph of the five scenarios with number of fish on the y axis and years on the x axis. Write the data collected below: Activity 3: Construct a scenario in which the population of humans and fish last for 1000+ years. What are the various factor values for this scenario?