Why Grizzly Bears and the “Bird Pines” are Dependent on Clark’s Nutcrackers

Clark’s Nutcracker Looking for Limber Pine Seeds
Clark’s Nutcracker Looking for Limber Pine Seeds

There are many species of pine trees in the Northern Hemisphere. Some of them have relatively light weight seeds, with wings, that are dispersed by wind. Some pines, such as white-bark pine and limber pine in Yellowstone have large seeds that are eaten by many species including squirrels, grizzly bears, and Clark’s nutcracker.

Clark’s Nutcracker With White-Bark Pine Seed
Clark’s Nutcracker With White-Bark Pine Seed

Clark’s nutcrackers are in the jay and crow family and were named for Clark of Lewis and Clark. Like the other birds in this family the Clark’s nutcracker is smart. In the fall it can collect and cache in the ground almost 100,000 white-bark and limber pine seeds. It usually places 4 seeds in each cache so that means it has as many as 25,000 caches. It not only remembers these cache sites, it can find them under 3 feet of snow! Do you remember what you had for breakfast 3 days ago. I don’t!

Clark’s Nutcracker Looking at a Limber Pine Seed
Clark’s Nutcracker Looking at a Limber Pine Seed

Notice in the second photo the nutcracker is sitting on a white-bark pine where it has been digging the seeds from the cones. In the above photo a nutcracker is looking for limber pine seeds on the ground. White-bark pines don’t drop their pine cones but limber pines do.

A Clark’s Nutcracker With a Limber Pine Seed
A Clark’s Nutcracker With a Limber Pine Seed

White-bark and limber pine both produce large seeds and depend on the Clark’s nutcracker for their dispersal. Although the nutcracker can remember all of it’s caches it usually buries more than it needs so it effectively disperses and plants many pines seeds, some as far as 20 miles from the pine the seed came from. In doing so it not only insures its own survival but also the survival of animals such as grizzly bears who depend on these high calorie seeds in the fall to build up fat before their winter hibernation. Due to global warming white-bark pine have radically declined in the last 15 years. Nutcrackers have helped insure white-barks are planted in many diverse habitats giving them a better chance to survive, thus helping grizzly bears and other animals as well.
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A Clark’s Nutcracker Preparing to Bury a Limber Pine Seed
A Clark’s Nutcracker Preparing to Bury a Limber Pine Seed
Clark’s Nutcracker Burying a Seed
Clark’s Nutcracker Burying a Seed

2 thoughts on “Why Grizzly Bears and the “Bird Pines” are Dependent on Clark’s Nutcrackers

  1. Very cool! Great images and good to see the difference between the white bark pine and the limber cones. No, I can’t remember what breakfast was, unless I have the same thing every day. So, the nuts would be lost forever.

    1. Yes I would starve as well, especially when they are under 3 feet of snow. Even if I did know where they were I don’t know if would dig through all that snow for 4 seeds.

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