Bears - Sounds Wild
Home on the Home Range

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Home on the home range

A lanky, three-year-old female grizzly bear walks beside a stream in a forest in British Columbia. She's exploring. She was born a dozen miles away, in her mother's home range, and she lived in that watershed until this spring, when her mom chased her out. She's looking to establish her own home range.

This is known as dispersal. A study of grizzly bears in Southwest Canada found that on average, young adult female bears dispersed about 10 miles from the center of their mom's home range, establishing an adjacent home range that is roughly eight miles by eight miles square, or 64 square miles. Dispersing male bears moved about three times as far and had home ranges about three times larger than females.

Productive systems with salmon can support a lot of bears, and their home ranges are relatively small. Bears in less productive systems have much larger home ranges, and need to cover a lot more ground to meet their needs.

Home ranges are not territories, which are defended and exclusive. Bears have overlapping home ranges and are generally tolerant of neighboring bears, as long as they are not competing to be in the same place at the same time, like a choice fishing spot, or competing for a mate. A home range is similar to a territory: animals learn where to find the resources they need throughout the year - for bears that is berry patches, salmon streams and other food sources, and places to den up and hibernate.