I saw birds storing seed from the bird feeder in tree niches during the fall, but it looks like that behavior is important in the winter as well. The White-breasted Nuthatch who provided the comical poses the other day was intent on caching both sunflower seeds and suet in the cracks in the bark of the buckeye tree.
The only drawback of this strategy is that other birds may avail themselves of the resource, once they discover the wealth of riches hidden in the tree. Perhaps the cached food is only seen or removable by birds who forage in the head-down position, like the nuthatches, safe from all the woodpeckers and chickadees that cruise the bark as well.
It’s probably just as well that birds don’t count on us unreliable humans who fail to fill the feeders on time, or who leave town for extended periods without providing back-up feeder fillers.