Predator-Prey Relationships Background In this case study you will look at one of the most famous sets of data ever collected on a predator-prey relationship. Lynx are a type of wildcat that inhabit the forests of Canada and prey on snowshoe hare. In some areas, the snowshoe hare provide over 70% of the lynx diet. As a result, the population growth curve of the lynx should show a relationship to that of the snowshoe hare. The data on this relationship is shown in the graph below. Study the data as carefully as you can before answering the questions that follow. Data Population Numbers of Hare and Lynx by Year 100000 Population Numbers 90000 80000 70000 60000 50000 40000 Hare Numbers 30000 Lynx Numbers 20000 10000 1895 1900 1903 1905 1908 1909 1910 1912 1915 1918 1921 1924 1927 1930 1933 1934 1936 0 Year Questions 1 Which animal is the predator and which is the prey? 2 As the hare population increases what happens to the population of the lynx? Why do you think is? 3 As the lynx population increases what happens to the population of the snowshoe hare? Why do you think is? 4 The population growth curves are said to fluctuate, what do you think this means? 5 Using the graph to help, how many years are there in one fluctuating cycle of the hare population? 6 What factors could be responsible for the unusual number of hare in 1895? 7 A good predator-prey relationship keeps the two populations “in balance”, what do we mean by this? 8 What would happen to the forest environment if the lynx started being hunted for their skins? Challenge 9 Explain the changes, if any, the introduction of a second predator of the snowshoe hare would have on the predator-prey relationship shown above?