Voted Best Answer
May 17, 2020 - 07:58 AM
What you describe is very likely the pest Plodia interpunctella or more commonly known as the Indian Meal Moth. They are the most common pantry pest in homes that easily find their way into bran, chicken meal, cereals, etc.
They have the ability to chew through plastic and cardboard and even infest sealed containers!
You should throw out all your bran that is not in very tightly sealed containers. You can also prevent them very easily in the future by freezing them or microwaving any new grains introduced into your house.
I buy Rubbermaid containers to store all my flours and brans in at home. You can also store them safely in your freezer.
I'm so sorry to hear your home has them, but you can quickly be rid of them by using Pantry Pest Traps
You can also use products like boric acid and diatomaceous earth in your pantry to prevent future moths from entering. Here is a very good article about using them: