A few common white cultivars can still be in fruit at flowering time the following year. Grignon hawthorn and strawberry tree also do this.
In our garden, the birds are too hungry to leave any edibles behind. All the berries on our Skimmia japonica are gone. Sigh! I was hoping they would still be around for Christmas. At the rate these crab apple fruits are being eaten up, they will be gone before christmas too. The American beauty berries Callicarpa americana follow in January and February. At least, they leave the rose hips alone - I figure out that I can still safely leave the hips from the current season's crosses on the plants a little longer.
Don't know. Never did see the culprits. They are most likely nocturnal, because those berries were there one day and gone the next morning. So, maybe it's not birds. Can't think of any nocturnal birds that are non-carnivorous around here.
Sounds like Rodentia. However, skimmia berries seem to be about on the top of the list of poisonous garden plant parts that are warned about here.