I guess not ?!

Rabbits? Rabbits might come in the evening but they'd have to be very tall! Ducks? I think the ducks only come during the day.
Rats would eat everything. Maybe raccoons, they eat at night and it could be that the highest branches give way under their weight.

No ducks or rats here, but rabbits, possums, and raccoons are possible, I've had them in the yard. And chipmunks!

Was driving around the other day noticing other's winterberry shrubs by the road, well endowed with berries, not like my bare torso hollies. Sigh.

Maybe I'll spray the shrubs next fall, experiment with a repellant.

Do you have rub marks on the branches that used to have berries. The thought struck that a buck could be using your tree to remove velvet and shaking just enough to dislodge the berries.

Thanks for that input maifeur, actually I discovered today, after yesterday's 18" snowfall, that a deer visited. Tracks around the bird feeder table, and onto the I. verticillata's. It even pee'd right next to them. While following it's tracks today, it dawned on me that deer don't reach up high to eat, they browse lower, more like knee to waist level on humans. It explains the berries missing. And why other property owner's plants, near the road, don't get eaten, because of the road being more of a threat.

My property out front is difficult to fence shut from deer. I sprayed a couple weeks ago, but we've had so much rain, it's a challenge.

Even deer have favorites. As the forage is used up deer will start eating higher on the plants. Now that you know about the deer perhaps for next year you can plan some sort of barrier. Pickett's maybe?

I will plan for next fall's harvest with different ideas. Clear or black plastic mesh netting perhaps...

I thought of this thread today when I was watching This Old House Hour on PBS. A person had trees that were eaten similar to this. The show showed a good distance to prevent the plants from being eaten along with how/when/type of fencing to use.

Although they used temporary fence poles I would be tempted to make perminant decorative poles at the distance they used. Perhaps to make them look like they should be there rather than an after thought plant flowers or one of the clementis's that must be pruned in the spring on the inside of the post so that it will wrap arround but in winter will not be stomped.

You can probably look at the episode by checking PBS's or This Old House's websites.

After my husband happened to see 4 or 5 deer run across our lawn last week, I'm thinking harder about partial fencing. That's a dilemma, as having one caught inside your yard is asking for more problems. Total fencing is not an option as I'd have to fence the driveway shut. I share the drive with a neighbor, and I have a home business with visitors so -
Thanks for the tip though maifleur

The fencing must be close enough to the plant so the deer feel unsafe to jump over the fence but far enough away for them not to be able to reach the plant. Deer can leap over high fence if they are running or really want to go to the effort so fencing the entire lawn unless with a 10-12 ft tall fence will not keep any deer that WANTS to come in out.

The show used four taller than normal fence posts with black plastic fencing on it. I want to say that they used 2 widths of it to get the necessary height. With the black plastic fencing such as used to keep birds away from fruit most people are not able to see it unless backlighted.

I guess I'm a bit confused by your question. I thought the reason for planting winterberry and other native food plants was to provide food for wildlife! It seems to me that you are being successful.

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