Look like deer droppings to me. Perhaps some other herbivore.

After googling 'rabbit poop', I think it is from rabbits. I live in the city with a fenced in yard. I highly doubt that it is from deers. I heard it makes good fertilizer for the garden.

Now I understand how my viburnum got 'trimmed' without my permission. What can i use to get rid of rabbits?

Deer droppings are more oblong in shape. It looks like rabbit droppings to me (We have a pet rabbit so I see droppings like this every day).

A few solutions. First is to spray your viburnums in late fall with Bobbex or some other brand of rabbit repellent. They usually have a summer rate and a heavier winter rate listed on the back of the bottle.

2nd option is to put up chicken wire around your viburnums for the winter months only for a preventative barrier.

3rd option is to use a Hav-a-Hart trap baited with an apple, carrot or some broccoli and move the rabbit far away to hopefully a better home.

Last option is hot lead to the head, but I cannot do this since I like rabbits so much. I have learned to live with them but take precaution if I still want to grow plants outside.