This is in a garden in a 6b zone. The garden is shaded a big part of the day. I don't live nearby, so I can't watch what's happening there.
I'd place the blame on squirrels or more likely, field mice. I opened your image in another window and it looks like scrape marks from incisors. Have you ever seen either about? Squirrels are bolder and far more visible. You'd see mice rarely and never while you were outside.
I'm not say Stephie's wrong and I'm right. I'm only adding another possibility. I've found mice and squirrels love bulb plants too (excluding garlic, onions and leeks).
I'd blame slugs.
Partly because putting the blame on them means one will be right in like 50% of all cases, partly because I see no clear bite marks, which fits with their method of eating by rasping off parts of the plants.
Yes, there are no slime traces, but slugs need to expell less slime in shaded, more humid areas and if you had some rain, it might also be washed off (are those droplets on the grass and leaves rain, dew or from watering?).
And finally, I have noticed that at least in my garden slugs show a clear preference for everything with a bulb, whether allium, tulips or something else.
It looks like incisors or just plain old damage. If it continues, one could spray some tabasco on it cut with a pint of water and two drops of dish soap. It seems like they didn't like it because the stalk is still there. My squirrels and rabbits figure out something's good and finish it off. I have found planting garlic or green onions amongst things keeps 4, 6, and eight-legged critters away. I'm planting out 40 baby amaryllis bulbs this weekend, so you've got me worried. :-o