20+ Interesting Facts About Grizzly Bears

1. The grizzly bear, a subspecies of brown bears, is native to North America. Compared to brown bears in other continents, they are known as grizzly (streak with grey hair) due to their white-tipped brown fur.  
2. Grizzly bears originated in Asia around 1.3 million years ago. It migrated to North America through the Bering land bridge roughly 200,000 years ago. The ancestor of the grizzly bear is the Etruscan bear, which lived from 5.3 million years ago to 10,000 years in Eurasia and Africa. (Source)
3. Adult grizzly bears can reach 2.5 m (8 ft.) in length and attain a weight of around 410 kg (900 lb). Males are considerably heavier than females. 
4. Grizzly bears have the 2^nd lowest reproductive rate for terrestrial mammals in North America after musk ox. Females reach breeding maturity between 4 to 9 years and breed after every three or more years.  
5. The claws of grizzly bears can grow up to 4 inches long. These long and powerful claws are ideal for digging the ground, catching salmons, constructing large dens, and ripping apart tree stumps for insects. (Source)
6. Digging soil by grizzly bears is beneficial for plant life. Their digging style assists the reproduction of old, deeply seated plants. (Source)
7. The highest known population of grizzly bears was more than 50,000. It reduced to between 600 and 800 during the 1960s. Currently, there are 1,400 to 1,700 grizzly bears in the contiguous US.
8. Grizzly bears have a bite force of more than 8 million pascals. These bears can even crush bowling balls with their powerful bite.
9. The average lifespan for grizzlies is 25 years in the wild and 30 years in captivity. Females usually live longer than males.
10. A grizzly bear is depicted on the flag of California, but the animal is not physically present in this US state. The last grizzly bear was shot dead in California in 1922. Later, it became the state animal of this state in 1953. (Source)
11. Grizzly bears hibernate for five to seven months each year. They experience complete hibernation in winter and remain semi-hibernating during spring. (Source)
12. The mating season is from June to July and female grizzlies give birth in January or February during hibernation. Usually, twins are born.
13. Grizzly bears are generally solitary mammals. Only mothers are seen with cubs, while males unite with females during mating seasons.
14. Grizzly bears are members of the order Carnivora, but their diet is omnivorous. They eat almost everything in their environment, including grasses, fruits, seeds, elk, bison, etc. (Source)
15. Grizzly and polar bears are closely related and have been mating for thousands of years. However, these matings happen occasionally, and the grizzly-polar hybrid is not visible commonly. (Source)
16. Despite being weighty, grizzly bears can run at speeds up to 30-35 mph. It is due to their muscular physique. The muscular hump at the mammal’s back assists in achieving swiftness while running. (Source) 

    

    Young grizzly bears can climb trees efficiently

    
    
17. Young grizzly bears can climb trees effectively. It is difficult for adult grizzlies due to their weight and claw structure. However, they can climb trees with ladder-like branches.
18. In 1807, US President Thomas Jefferson received a gift of a grizzly bear couple (male and female) from an explorer. The president put these bears in a cage near the entrance to the White House for some time. (Source)
19. Apart from color, several other differences distinguish grizzly bears from black bears. Grizzly bears have a prominent hump, rump lower than the shoulder, and long, light claws compared to black bears. (Source)
20. Female grizzly bears and other brown bears protect their cubs from the infanticide behavior of stranger male bears. For this purpose, these female bears take their cubs closer to the human settlements. (Source)
21. Grizzly bears are the main threat to the moose population in the Yukon. Grizzly bears were responsible for 50% of deaths related to adult and calf moose between 1983 and 1985, which is far more than the deaths caused by wolves and humans. (Source)
22. If the availability of fish is high, grizzly bears only consume energy-rich fish and their nutritious body parts. But in case of scarcity of fish, these bears will eat the entire fish. (Source)
23. Grizzly bears are known to attack humans if they enter their habitat. In the Yellowstone region, grizzlies have killed eight people since 2010. (Source)
24. Grizzly bears are listed as Least Concern on IUCN Red List. They were listed as threatened in 1975, but their numbers have increased more than five times due to conservation efforts.