Ecosystems A to Z

Science Center Objects

Did you know that the USGS Ecosystems Mission Area is the biological research arm of the U.S. Department of the Interior?    

USGS Ecosystems Mission Area scientists are leading research and monitoring efforts across the country and in some cases around the globe. Studying topics from amphibians to zoonotic diseases, they provide natural resource managers with the information and data needed to make decisions about the nation’s wildlife and wild places. In the Ecosystems A-Z series, we’ll share just some of the work our scientists are leading from A-Z, and now B is for Bears.

B is for Bears

In this this installment we take on the letter B and the work we do on bears! Test your knowledge about USGS bear research with this short quiz. 


  1. True or False: Studying bears requires talking to people. 
  2. Select the correct answer. USGS scientists’ study polar bears: 

    1. Using models 

    2. Doing mark-recapture studies 

    3. Using radio-tracking 

    4. Going to the zoo 

  3. True or False: Grizzly bears steal from squirrels.  

  4. True or False: USGS bear experts only study bears in the U.S. 

  5. Can you tell which is the black bear and which is the grizzly bear?  

Image: Female Grizzly Bear with Cub

(Credit: John Way . Public domain.)

Image: Louisiana Black Bear and Cubs

(Credit: Clint Turnage, USDA. Public domain.)


  1. True. In Massachusetts, black bear populations are growing in size and distribution, and USGS Cooperative Research Unit scientists recently worked with partners to survey residents on their attitudes toward the bears. The black bears are expanding into areas where the general public has little or no experience with bears. The survey results will help researchers understand residents’ opinions on the bear population, their experience with black bears, and opinions of the bear population and its management. 
  2. Image: An Adult Polar Bear and Her Two Cubs

    An adult female polar bear and her two cubs travel across the sea ice of the Arctic Ocean north of the Alaska coast. (Credit: Mike Lockhart, USGS. Public domain.)

    A, B. & C.   A)  Models of polar bear distribution and habitat use, based on data collected by satellite collars placed on adult female bears, help tell the story of how these bears are responding to long-term declines in their sea ice habitat. Managers can use these models to help make decisions on how best to lessen the likelihood of further adverse impacts to polar bear habitat.  B) USGS scientists have used mark-recapture methods to study the status and trends of polar bear populations in the Southern Beaufort Sea and Chukchi Sea. C) Based on data collected from radio-tagged adult female bears, USGS scientists have learned that most maternal denning has shifted from sea ice to land and now occurs at relatively high densities along the central and eastern Arctic coastal plain of Alaska.

  3. True. According to the USGS-led Interagency Grizzly Bear Study Team, whitebark pine seeds are a high-calorie food available to grizzly bears during late summer and fall. They harvest these seeds by raiding food caches (middens) of red squirrels. Whitebark pine seeds are high in fats and proteins and when seed production is good (every 2 to 3 years), it helps grizzly bears build up fat reserves during fall in preparation for hibernation. 

    Mother grizzly and cub at Gibbon River, Yellowstone National Park.

    A USGS grizzly bear researcher snapped this picture of a mother grizzly bear and her cub in Yellowstone National Park. Adult females are the most important segment of the grizzly bear populations because they are the reproductive engine. (Credit: Frank van Manen, USGS. )

  4. False. USGS scientists lend their expertise around the world. For example, USGS New York Cooperative Research Unit scientists are working with partners in Ecuador who are monitoring the endangered Andean bear to understand threats to their populations and to help inform management decisions. Scientists at the USGS Northern Rocky Mountain Science Center are collaborating with researchers in Malaysia to inform conservation of the least-known and smallest bear species, the sun bear. USGS scientists are also active members of the International Association for Bear Research and Management (IBA) and serve on the International Union for Conservation of Nature (IUCN) Bear Specialist Group and the IUCN Bear Monitoring Expert Group. 

  5. The first image is of grizzly bears and the second, black bears.  USGS scientists study both grizzly bears and black bears. There are clear distinctions between the two, such as the distinctive shoulder hump on the grizzly bear, which is a large mass of muscle used for digging. Black bears are generally smaller and have more of a straight facial profile than grizzly bears. Fur color varies a lot for both bears and is not always a good identifier. For information on accurately identifying these two bears species, visit: 


Thanks for taking the quiz, and look for our next installment in Ecosystems A-Z. We’ll be talking about Chronic Wasting Disease.