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Gray squirrels often forget where they bury nuts, which then have a greater chance of sprouting.
CHICAGO, Illinois (Reuters) -- Gray squirrels' faulty memories turn out to be good for forests, but the nut-hoarding habits of their red cousins are not, according to scientists.
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 researcher said Tuesday.
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.
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