Artificial Nest Have Often Been Used When Biologists Study Predation

Essay

Artificial nest have often been used when biologists study predation on birds. It is usually assumed that predators will respond to artificial nests in the same way they do to real birds' nests. A recent experiment was performed to check this assumption for predators of the American robin (Turdus migratorius) by comparing the egg loss in three experimental treatments: (1) natural robin's nests, (2) artificial wicker-basket nests placed 30 meters in a random direction from natural robin's nests, and (3) artificial wicker-basket nests placed in a 180 m by 240 m grid around robin's nests. The data below are cumulative counts of eggs predated (stolen or broken and eaten) at 5, 10, and 15 day points of the experiment. ​ (a) Construct a bar chart to display the cumulative counts for the natural robin nests at their 5-, 10-, and 15-day checks. (b) Fill in the relative frequency distribution (table) representing the cumulative counts for the artificial nests in the grid. (Do not convert the table to a graph.) ​