If you choose a single seed, consider the black oil sunflower which is preferred by chickadees, cardinals, nuthatches and finches. It is less likely to attract blue jays and non-native sparrows and starlings. Suet provides another opportunity to feed chickadees, nuthatches, blue jays and starlings, while also attracting downy and hairy woodpeckers. Available in most grocery stores, it should be hung well above the ground in a wire basket or mesh bag to prevent dogs and raccoons from reaching it. The factor that most hinders the survival of birds in winter is not food.
Water is often harder to come by than food due to frozen conditions.
Offering water in a pan, birdbath or even trash can lid can be difficult in very cold conditions. Serious bird watchers may wish to invest in a small electric immersion heater. These devices turn off when the water has dried up, and the effect on overall electric costs isn't noticeable. Of course, antifreeze should never be used in birdbaths because it will kill animals. To minimize birds hitting windows, place feeders closer than four or greater than fifteen feet away.