Congratulations to Gail Coffey, the first NC reader who recognized the signs of Pine Grosbeaks feeding on crab apples! Snow discolored by bits of uneaten fruit usually indicates feathered consumers have been in the tree whose branches are above the snow. The litter can consist of sumac seed coats, bittersweet bits, crab apple flesh and parts of other fruits that are available in winter, as many readers suggested. There are many birds that remain in or visit the Northeast in winter and consume fruit (Northern Cardinals, Crows, European Starlings, Blue Jays, Cedar and Bohemian Waxwings, Eastern Mockingbirds, American Robins, etc.).
When it comes to crab apples, most birds tend to swallow the entire fruit, leaving some bits on the snow, but nowhere near the amount pictured in the Mystery Photo. Pine Grosbeaks, occasional winter visitors from further north, are crab apple eaters but unlike most other species they tend to mash the crab apples in their stout beaks and swallow only the seeds. The fleshy uneaten parts of the apples accumulate on their beaks until the load becomes heavy enough to fall to the ground, coloring the snow below red.
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