Clark’s Nutcracker–photos and links

Often you’ll hear Clark’s Nutcrackers long before you see them.  Their distinctive voices carry far distances and permit the certain identification even if you never see them.  Click here to hear a sample.  Look for the “typical voice” section about 1/2 down the page.

Clark’s Nutcrackers are champion seed gatherers.  One bird in Yosemite Park stuffed 70 seeds in its sublingual pouch (a structure under its tongue).  Another study documented a bird carrying as many as150 nuts at once.  Since they often travel so far between the sites of a good seed crop and their high-altitude caching areas, this ability to pack in so many seeds per trip saves some serious travel time.

As specialized caching birds, corvids in general can remember thousands of individual locations.  Those species that rely most heavily on their caches, such as nutcrackers, have the best memories.  Research has provided some insights into the amazing spatial memories of these remarkable corvids.  Using visual clues from relatively large objects in the environment (for example, a distinctive tree, a rock, a fallen log), a nutcracker’s relocates its cache sites using the spatial relationships between these landmarks and the hidden sites.  A bird’s recollection of cache locations has been retained longer than 9 months, although accuracy seemed to decay after about 6 months.  Corroborating these controlled field experiments, observers in the field have noted nutcrackers retrieving caches more than 9 months after hiding seeds there.  (And I can’t even remember what I had for lunch yesterday.  Good thing I’m not a nutcracker—I’d be out of the gene pool in no time.)  Forgotten or unused seeds likely help to regenerate coniferous woodlands and forests.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s