Classroom Questions

Questions for ‘Polar bears leave thousands of tons of food scraps for other species’ 

a polar bear stands on a sheet of ice with a bloody carcass of a dead animal in front of it, while seagulls stand nearby

A polar bear in Norway picks at its prey. Gulls nearby and other animals will eat the leftovers. Polar bears typically leave about 30 percent of edible animal’s remains.

David Merron Photography/Getty Images

By Science News Explores

To accompany ‘Polar bears leave thousands of tons of food scraps for other species’

SCIENCE

Before Reading:

  1. What sets a top predator apart from a typical predator? Give one example of a top predator. What is one way that predators — top or otherwise — might help their ecosystem? Your answers can relate to predators in general or to a particular species.
  2. List three basic things that every animal needs to survive. Compare the ease of obtaining each of these in an Arctic environment vs. a temperate forest environment.

During Reading:

  1. What is the total amount of prey one polar bear leaves behind each year?
  2. Give two examples of parts of prey that a polar bear would typically leave behind.
  3. What types of studies did researchers include in their analysis?
  4. Approximately how many kilograms of prey does a typical bear kill each year?
  5. What is the most common prey of a polar bear?
  6. Approximately what percent of the prey’s mass does the bear actually consume?
  7. List three animals known to seek out and scavenge the remains of polar bears’ prey.
  8. How is melting ice affecting the availability of this food source?

After Reading:

  1. Refer to your answer to Question 4 in During Reading. It would have been possible to calculate this number, even if it had not been provided to you. Search through this article, paying close attention to the numbers and find a way that you might have calculated this value on your own. Show your calculations and briefly explain your answer. (Hint: Consider the following questions when developing your answer: How many kilograms of prey does a typical polar bear leave for other animals in a year? What percentage of a prey’s biomass does a typical polar bear consume?)
  2. As the Arctic warms, polar bear populations decline. What is a direct effect of population decline? Explain how this effect could cause changes to other species in the ecosystem.