In much of North America, winter is a rugged time for birds. Days are often windy and cold, nights worse, with temperatures falling, many times below zero. Birds that rely heavily on insects in their diet quickly fall on hard times. Frozen lakes, rivers, and ponds mean water is even more difficult to find. Shelter disappears with the leaves. Pine trees offer some salvation, probably the best natural shelter in winter, but many places do not have pines.So, how can we help?First, serve seed that is highly nutritious, as it will provide the energy birds need in the winter. The seed with the most bang-for-the-buck is black sunflower seed. It is high in protein and fat, readily available, and not too expensive. It has twice the calories per pound as striped sunflower seed. If you put out mixed seed, serve a high quality mix with a healthy portion of black sunflower seed. Seed can be mixed with fruit or suet pieces, too. Suet plugs and cakes are excellent sources of protein, and can contain insects and fruit as an ingredient. Remember, too, that not all birds have heavy-duty beaks for breaking into seeds, so occasionally serve seed without hulls, such as hulled sunflower seed or no-waste seed. Safflower seed is another highly nutritious seed, and it is enjoyed by many species, especially the Northern Cardinal. If you mix safflower (a white seed) with black sunflower, not only is it healthy, it will be more visible, which is how most birds find their food.When it comes to feeders, you can hang a clear plexiglass or plastic feeder, such as the Sky Cafe, so all the seed is visible. A platform feeder with a transparent top is ideal too. So you don't have to trudge through the snow too often, set out larger feeders that need to be refilled less often, and if possible, move them closer to your house (within three feet, or on the window). Window feeders are often the easiest option to watch over, fill and maintain. These tricks will help to assure that birds have seed all winter. Choose hopper or platform feeders that have roofs that extend over the feed area so the seed is protected from the elements. Make certain there are screen bottoms or drain holes so the seed doesn't sit in moisture and turn moldy. If you use tube feeders, look for feeders that have seed dividers at the bottom so the seed is moved to the bottom ports and not allowed to sit and become moldy. Also, make certain that the tube feeder is easy to clean so the bottom can be quickly removed and all old seed easily disposed of, like the Aspects Quick-Clean Feeders. To protect a tube feeder from the elements, place a clear top or dome over the feeder.Freestanding water is also a must for birds, but it is difficult to find when the temperatures drop below the freezing mark. If you have a birdbath suited for the cold weather, you may add a heater to the water in the basin to keep it free from ice. The heaters are safe, relatively inexpensive to operate, and affordable. In lieu of a birdbath heater, a heated birdbath is ideal. It will keep the water unfrozen through even the harshest temperatures. The new-generation birdbath heaters and heated birdbaths have thermostats that regulate the heaters, turning them off when the temperatures exceed freezing, saving energy and reducing cost. Many operate at the cost of a modest light bulb.Happy Winter Backyard Birding!