Two grizzly cubs that were orphaned this week when their mother was killed for attacking and partially consuming a hiker in Yellowstone National Park will be sent to the Toledo Zoo in Ohio.

The cubs are less than a year old, which wildlife officials say is too young to survive in the wild without their mother, zoo officials said in a release Friday. "The twins currently weigh approximately 50-60 pounds each. When fully grown, an adult female grizzly can weigh up to 500 pounds," it added.

The exact arrival date for the cubs is yet to be determined, but is anticipated to be this fall. Yellowstone officials could not immediately be reached to say where the cubs would be held in the meantime.

Upon their arrival at the zoo, the cubs will undergo standard quarantine processes to ensure their health and wellness before going on exhibit for public viewing. Additional details about the cubs and their exhibit space will be announced after their arrival, the zoo release said.

Grizzly bears are a North American sub-species of brown bears. Grizzlies were once widespread throughout western and plain states; however, their population decreased dramatically with the development of the west. Today only 2,300 live in the four states of Wyoming, Montana, Idaho and Washington. The U.S. Fish and Wildlife Service lists grizzly bears as threatened in the lower 48 states.

It has been over 30 years since brown bears resided at the Toledo Zoo. When the cubs arrive, the zoo will then be home to three bear species: grizzly, polar and sloth.