Reading H.D. Thoreau’s writings on seed dispersal, from some 150 years ago. He writes of his observations of squirrels and their penchant for burying and retrieving nuts, and asks rhetorically, Do they find them by scent or memory? I believe that I’ve seen studies indicating that they do rely to some degree on memory, but I wonder what we know now about the process. It’s particularly intriguing when squirrels find buried nuts below a foot or more of snow, with few landmarks available to see or to smell. What’s the S.D. on how squirrels find what they’ve buried? And do they only dig up what they’ve buried, or do they dig up the caches of other squirrels, too?
It’s memory. And the study I read on the subject says that they forget where about 80% of the nuts are. This is one reason why squirrels are such a great resource to trees - they’re not giving up very many seeds compared to the huge advantage of having squirrels carry them all over the forest.
Of course… in my yard, the crows have learned to watch squirrels. As soon as the squirrel leaves, the crows dig up whatever got buried. Sometimes they eat it and sometimes they don’t, but you can be sure it’s not there when the squirrel comes back.
Any chance you can find a citation for that study? Quick searches indicate that the question is still pretty much up in the air.
Did you think up that title just to induce smart-ass responses?
:smack: innocent me - I didn’t even think about it. But knowing what adolescents we are on this site, I should have.
Unfortunately, it’s been a long time… 15 years ago, I was in a college course about the local (central coast of CA) ecosystems, where we talked about squirrels and acorns. We were using a lot of current literature (half of which was published by the professor, I’m sure) but I don’t recall much of the details.
I realize that my front yard is not an accurate representation of the world’s squirrel population but, judging from the view from my front window, they just bury so many seeds/nuts between them all that you’d be hard pressed to dig a couple holes and not find something there to eat.
This might not work in the deep virgin forest where the squirrel population density is probably lower.
When I take a walk in the nearby woods during winter, I’ll find squirrel tracks, and dug up nut caches, everywhere. It doesn’t take that many busy squirrels to load almost every conceivable woodland nook and cranny with a treat. No memory needed.
Sometimes you feel like a nut.