Want to help birds through the cold winter? Set this out in your yard

One ounce of chocolate fudge contains about 120 calories. One ounce of beef suet has 280 calories.

If you're a bird, fudge definitely is for dessert.

Suet, the main-course item, is a hard fat that surrounds cow kidneys. An average cow yields 10 to 15 pounds of suet. That's enough to feed birds in our yard for much of the winter.

I buy suet 20 pounds at a time, a dollar per pound. I get it from a small-town butcher who actually butchers.

High energy content — fat and protein — makes suet a great winter bird food. Birds have high metabolisms. They need calorie-rich food.

The bird species that eat suet also eat insects. Birds find insects in the winter, in climates like ours, by probing behind tree bark and into other cracks and crannies (nuthatches, chickadees) or by chiseling into trees (woodpeckers).

The nutritional value of insects for birds can be seen in an analysis of insects for a human diet, keeping in mind that birds probably eat a wider variety of insects than you might choose, if you were so inclined.

Insects eaten by humans range from 10 to 60% fat. Most commonly eaten are beetles, caterpillars, wasps, bees, ants, grasshoppers, locusts and crickets. I cannot speak from experience.

Fat content is higher in insect larval stages. Caterpillars in particular have a high fat content. Protein, also available from insects, has about half the energy value of fat.

Mealworms, the larval form of a beetle, are a good energy source for birds. They are available in most wild bird stores, live or freeze-dried. Live ones keep well in a small plastic tub in your refrigerator. Cover them tightly.

Three ounces of mealworms (I did not count individuals) contain 6 grams of carbs, 12 grams of fat, and 20 grams of protein.

(According to the NFS, the nutrient score for mealworms is better than either beef or chicken. Incidentally, did you know that crickets, grasshoppers and silkworms have three times the antioxidants of orange juice? And shellfish, like lobster, share a family with insects.)

You can make your own suet cakes. Boil raw suet pieces in water to separate the fat from fiber. Add other ingredients, if you wish, then pour the concoction into containers that create an appropriate shape. Cool in the fridge. (Mark the container.)

Do not render suet over direct heat, and certainly not in the oven. You will stink up the house.

Suet is best stored in your freezer if you're keeping it for more than a few weeks. It thaws quickly when serving time arrives.

You can feed suet in purchased containers or build your own with hardware cloth, or simply hang it in a mesh bag.

Suet can be offered to birds year-round. It melts in hot weather, though, and drips, and can damage the natural waterproofing on bird feathers. Crows and starlings like suet, but squirrels don't.