Certified GKH Gardening Expert
Unfortunately, I don't think there will be any way to save this plant's crop, since most of the damage has been done. You will have to fence off the area, or keep animals out by any means necessary.
If you suspect that this is insect damage, than an insecticide will help. This article will help: https://www.gardeningknowhow.com/special/organic/natural-home-pesticides-organic-garden-pest-control.htm
This collection of articles will offer information on common animal pests, and how to deal with them: https://www.gardeningknowhow.com/category/plant-problems/pests/animals