Fun with Science Club®


			Do lynx ride roller coasters? Carrie Straight 05.03.01 Lynx (Lynx canadensis) population numbers change from year to year. The numbers increase until they reach a certain level, then drop to a low point, and then rise again. This is called a cyclic pattern, because the population will be on a rise about every 10 years. These changes can be seen by looking at the graph, rising and falling in about ten years. These cycles for the lynx have been based on the number of pelts (fur or skins taken by lynx trappers) that were brought into the Hudson Bay Company. The Hudson Bay Company collected the furs and sold them to North American and European markets to be made into clothing and hats. The Company kept very good records of the number of furs the trappers sold to them. Two scientists wanted to see if these up and down cycles in the lynx population were similar for all regions of the north. The Hudson Bay Company divided Canada into different areas called regions. They wanted to know if the cycles of the lynx populations occurred over the whole country or if the cycles only occurred in certain areas. So these scientists read through loads of old records kept by the Hudson Bay Company. By looking at the records, they found that these cycles occurred in all of the areas, but that the timing of the peaks differed by a few years. This meant that all of the lynx in different regions might be affected by the same causes of population increase and decline. So this research brought up the new question: what causes the cyclic population changes in lynx? To be answered in another fun fact…


			Elton, Charles and Mary Nicholson. 1942. The ten-year cycle in numbers of the lynx in Canada. Journal of Animal Ecology 11(2): 215-244.