Exam (elaborations) GIZMOS Crump 13.3B CoralReefs 2 SE

Exam (elaborations) GIZMOS Crump 13.3B CoralReefs 2 SE Vocabulary (refer to vocab file located on the Gizmo site for definitions): biotic factor, black band disease, invasive species, white band disease Prior Knowledge Questions (Do these BEFORE using the Gizmo.) In 1992, Hurricane Andrew left a wake of destruction through Florida. One victim of the storm was a reptile-breeding facility. Over 900 Burmese pythons were set free, and today thousands of pythons live in Florida. These pythons are an invasive species, or a harmful species not native to the region. 1. What impacts do you think the Burmese pythons might have on local ecosystems? They’ll disrupt the normal food chain 2. In general, why might ecologists be concerned when new invasive species arrive in an ecosystem? It could cause another species to die off in the area Gizmo Warm-up: Like terrestrial environments, coral reefs can be damaged by invasive species. Reefs are also impacted by disease-causing bacteria, humans, and other biotic factors, or living parts of the ecosystem. In the Coral Reefs 2 – Biotic Factors lesson, you will explore how these factors affect coral reefs. 1. On the CONDITIONS tab, select Fishing. Set Net fishing to 50%. Click Advance year 10 times. What changes do you notice on the Coral reef tab? There is almost no fish life in the area 2. On the DATA tab, select every organism. What happens to the reef populations? The long-spined sea urchin, algae, and sponge populations rise and everything else decreases This study source was downloaded by from CourseH on :18:16 GMT -05:00 This study resource was shared via CourseH GIZMOS Crump 13.3B CoralReefs 2 SE Activity A: Fishing regulation Get the Gizmo ready: • Click Return to original settings and Restart. • On the CONDITIONS tab, check that Fishing is selected. Introduction: Fishing is a major part of many Caribbean economies. The yellowtail snapper and Nassau grouper are important food fishes. However, a lack of adequate regulation has led to overfishing in many areas and consequent damage to reefs. The goals of this activity are to observe the effects of overfishing and determine how much fishing the reef can withstand. Question: What are the effects of fishing on the reef ecosystem? 1. Describe: On the CORAL REEF tab, click on the stoplight parrotfish, queen angelfish, yellowtail snapper, and Nassau grouper. Describe what each of these fishes eat. Stoplight parrotfish: Algae Yellowtail snapper: Young fish, shrimp, crabs, worms Queen angelfish: Sponges Nassau grouper: snappers, angelfish, parrotfish 2. Predict: Set Grouper to 70%. How do you think this level of fishing will affect the populations of the other fish in the simulated reef? Explain your reasoning. I think it’ll cause fish population to increase and everything else decreases 3. Experiment: Select the DATA tab, and check that every species is selected. Click Advance year 10 times. Which fish populations increased, and which fish populations decreased? Decrease: Nassau grouper, stoplight parrotfish, queen angelfish Increase: yellowtail snapper, sponges, 4. Explain: Why do you think the snapper population changed the way it did? I guess the groupers usually ate the yellowtails the most 5. Predict: Click Return to original settings and Restart. Set Snapper to 70%. How do you think this will affect the other fish populations? Explain your reasoning. The nassau grouper population will decrease and then the rest will follow from the grouper decrease (Activity A continued on next page) This study source was downloaded by from CourseH on :18:16 GMT -05:00 This study resource was shared via CourseH Activity A (continued from previous page) 6. Experiment: Click Advance year 10 times. What changes occur? Less groupers and yellowtails 7. Explain: Explain the results of the last experiment. Why did the grouper, parrotfish, and angelfish populations rise? Why did the sea urchins decline? How did this affect algae? Snappers commonly ate young fish, maybe it was those types and that made more food for the groupers. Sea urchins and algae decreased because that was what a lot of the reef fish ate 8. Explore: Click Return to original conditions and Restart. Experiment with different levels of Net fishing. Net fishing kills all fish approximately equally. It also can damage delicate corals. For each experiment, run the simulation for approximately 40 years to see the long-term effects on the reef. Summarize the results of each experiment in the table below. Net fishing level Results 20% Not a lot of fish life in the reef anymore. Queen angelfish population went wonky. Grouper, parrotfish, and turtle populations lowered a lot 40% Again not a lot of fish life in the reef. Queen angelfish and sponge populations went stupid. Grouper, parrotfish, and turtle populations went to less than 5 60% Barely any fish life. Queen angelfish populations dropped but then reestablished a little. Parrotfish population was gone within 5 years; turtle, snapper, and grouper populations died within 14 years 80% No fish seen. Queen angelfish, parrotfish, grouper, and turtle populations disappeared within 23 years. All populations are decreasing other than algae 9. Draw conclusions: What level of net fishing can the model reef sustain? Explain. 10-20% for 100 years, one species dies off but if you go to 5%, theres a lot more widespread decrease in population. If you go any higher more fish will die but I think 10% is the ultimate best choice This study source was downloaded by from CourseH on :18:16 GMT -05:00 This study resource was shared via CourseH Activity B: Disease Get the Gizmo ready: • Click Return to original settings and Restart. • On the CONDITIONS tab, select Disease. • On the DATA tab, select every organism. Introduction: Corals are susceptible to many diseases, including black band disease and white band disease. Other reef animals are also affected by disease. For example, in 1983 a mysterious plague wiped out most of the long-spined sea urchins throughout the Caribbean. Question: How are reefs impacted by disease? 1. Observe: Select the CORAL REEF tab. Set the Black band infection rate to 100%. Click Advance year several times. Which coral appears to be affected, and what do you see? Boulder star coral decreases and there’s an increase for staghorn coral 2. Predict: How do you think the reef will change when black band disease is present? The star coral dies 3. Observe: Click Advance year until you reach year 20. What changes do you see? Star coral dies 4. Analyze: Look at the coral populations in the DATA tab. Why do you think the population of staghorn corals increased? There was more room for them there and maybe there was something in the makeup of the disease that allowed them to grow 5. Observe: Select the CORAL REEF tab. Click Return to original settings and Restart. Set the White band infection rate to 100%. Click Advance year two times. What do you see? Staghorn population decreases, everything else stays the same 6. Observe: Click Advance year to year 20. What changes do you see? Staghorn corals are dying and star corals are rising in population Confirm your observations by viewing the DATA tab. (Activity B continued on next page) This study source was downloaded by from CourseH on :18:16 GMT -05:00 This study resource was shared via CourseH Activity B (continued from previous page) 7. Set up the Gizmo: Click Return to original settings and Restart. Coral diseases often crop up in reefs that are already stressed by high temperatures, high nutrient levels, or low pH. To model these conditions, select Ocean conditions. Set the Ocean temperature to 29 °C and Ocean pH to 7.7. Then, select Land use and set Agriculture to 50%. Finally, select Disease and set the Black band infection rate and White band infection rate to 100%. Select the SUMMARY tab. What is the current coral stress level? 32% 8. Predict: How do you think stressed corals will respond to disease? They’ll die 9. Experiment: Click Advance year to year 20. How does the impact of disease in a stressed reef compare to the impact of disease in a healthy reef? (To make a direct comparison, run an experiment with the original settings and black and white band infection rates of 100%) 10.Predict: On the CONDITIONS tab, click Return to original settings and Restart. To model the die-off of long-spined sea urchins in 1983, set the Sea urchin infection rate to 90%. How do you think this will affect the reef? Algae will rise in population, certain fish will thrive and others wont 11.Experiment: Click Advance year to year 20. What changes occurred? Some fish populations decreased and others rose 12.Infer: Parrotfish rely on corals for protection and shelter. Look at the parrotfish population over time. Why did the parrotfish population increase at first and then later decline? Maybe there was less competition at first but then the corals