A river has different populations of lampreys and paddlefish. The paddlefish feed on zooplankton, while the lampreys feed on the paddlefish. Humans living around the river hunt the paddlefish. What will happen to the ecosystem if the paddlefish are hunted in excess?

If paddlefish are hunted in excess then the population of zooplankton will increase. Increases in the population of algae might lead to eutrophication. This can increase carbon dioxide levels in the pond. Also, reducing the population of the paddlefish limits the prey for lamprey and this can decrease their population.