Whether your point of entry is at the border crossing or airport, the rules are the same, you must declare all food, plants, animals, and their by-products. This is a direct quote from the Canadian Food Inspection Agency
: Travellers are required, by law, to declare all plant, animal, and food items they bring into Canada. This includes items related to plants, animals and food, or their by-products.
For more information, you can call the Border Information Service (BIS) at 204-983-3500 or 506-636-5064 from the US. Select 0 to talk to a person (not a machine).