Jeff-
You wrote:"I doubt the grey squirrels have had a significant impact on the oak/pine dynamic in the barrens."
And I would agree with you if we were to consider the "Pine Barrens" to be, collectively, a homogeneous biome, which, of course, couldn't be further from the truth of what the "pines" really are.
Your observation about finding red squirrels more frequently than greys the "deeper" you are (into the pines, I presume) speaks specifically to this point. It was my supposition back in the 60s (before I'd learned much about squirrel biology) that the reds persisted best in the regions where pines predominated almost to the exclusion of scrub oaks, and that as I got into areas where oaks began to reach parity with pines, greys were observed increasing frequency.
So the question occurs: what are the factors that favor incursion of oaks into previously predominantly pine climax forest? Fire? Soil pH? Water table? Certainly. And what about natural dispersants of acorns? They say "...the acorn doesn't fall far from the tree" True. So how do they wind up outside the the "drip line", the limits of the canopy of oaks?
Turn out that grey squirrels, with their preference for hardwood forests, have a penchant for caching mast - including acorns - at a distance from where they originally found it, and are thus important dispersers of the oak species ( and hickory and walnut as well...).
Red squirrels, with their appetite for conifer seeds, especially pine nuts, prefer coniferous forests and are definitely less common in hardwood forests. And as for the pine nuts they find? They tend to eat 'em where they find 'em and are not a significant disperser thereof.
Further north y'go, there's fewer and fewer deciduous forests. I've enjoyed watching the little red squirrels in the boreal pine forests and even in the taiga at the tundra's edge in Alaska and the Yukon - and nary a big ol' grey to be seen!
So, as fires open up the forest floor to re-seeding, are oaks, on balance, favored in the repopulation scheme-of-things? As folks around here in eastern South Dakota would say: "Ya sure, You betcha!"
This red squirrel-grey squirrel / pine-oak inter-relation is, to me, just one tiny component of the myriad relationships that contribute to what the Pine Barrens are and to the fascination that they hold for any observer of nature.
Ye Gads - I just re-read this. I do tend to ramble. Sorry 'bout that.
Dave
woodjin said:
I see red squirrels quite frequently in the woods. The deeper I am the higher the likelyhood of spotting a red instead of grey squirrel. I am surprised by the comments to the contrary. They are noisey.
Dave, I doubt the grey squirrels have had a significant impact on the oak/pine dynamic in the barrens. I havn't conducted a study on it of course, but I would doubt the population of grey squirrels are high enough to have seriously affected the balance. Controlled burning and wild fires have contributed most significantly to the pine dominant forest of present day.
Jeff