Gray Squirrels' Faulty Memories Help Forests


Nov 26, 8:07 am ET

CHICAGO (Reuters) - Gray squirrels' faulty memories turn out to be good for
forests, but the nut-hoarding habits of their red cousins are not, U.S.
scientists said on Tuesday.
The bane of suburban gardeners and backyard bird feeders, the ubiquitous
gray squirrel buries walnuts, acorns and other nuts across the landscape in
a pattern called "scatter hoarding," a Purdue University scientist said.

Some nuts are forgotten and have a chance to germinate and sprout into black
walnut, oak and hickory trees needed to regenerate steadily retreating
hardwood forests.

The red squirrel, which invaded the U.S. Midwest from higher altitudes
within the past century, usually piles nuts in a few above-ground caches,
where the seeds dry out or are eaten.

Seven times as many walnuts gathered by gray squirrels germinate compared
with walnuts hoarded by red squirrels, ecologist Rob Swihart said in a
statement released by the West Lafayette, Indiana, university. His findings
were published in the latest issue of the Canadian Journal of Zoology.