Black Birch is a great source of emergency food. Use the small twigs, inner bark, or the larger roots. The bark can be eaten fresh or cut into strips and boiled like noodles.
With the spines removed, the young leaves of the Bull Thistle can be added to salads or cooked as greens. The pithy young stems are excellent peeled and eaten raw or cooked.
The cattails will be one of the things we will require to survive. It has many uses. The top part that is brown can be broken open in fall and the fluff or pollen is great tinder for starting fires.
Your best is is to shoot one. If you do not have a firearm, an Atlatl, or slingshot or sling are your best bet for catching one. I would not recommend trying to drown one like I explained in the duck page.
The squirrel can be a great food source. It can be trapped, snared or shot.
You need a few to get full but they can be plentiful and fairly easy to catch.
The skunk is not the first thing on my list when I look for a food source but it is eatable. But as wilderness survival food they can be eaten.
Catching them is a little tricky, seeing as they will most likely spray you if you approach them.
The stinging nettle is a great source of vitamin A and C; it also contains manganese and potassium. You can collect the young shoots as well as the leaves.