Seed-eating birds get their food from a variety of sources throughout a day, so what people provide is a convenient and easy source of food, but not necessary to help the species of birds that come to feeders. So, starting or stopping your feeding at any particular time of year won't have much of an impact on those birds. The only exception is if there is a bad snow or ice storm and natural food is buried for a period of time. In that event, the seed you put out could be life-saving for some birds. Some people choose to only feed in winter, but others feed year-round to attract them closer to enjoy them up close.
Nectar-eating birds, such as hummingbirds and orioles, begin their migration north from the tropics in January. Hummingbirds may arrive in southern states as early as January, the middle states in March or April, and upper Great Lake states in May. As hummingbirds head south again, the birds farther north will stop at feeders along their way south; so some people leave their feeders out for a few weeks after they notice their summer birds have left, in the event passers-by stop to refuel.
For people who only feed during the summer, they can stop feeding in the fall whenever they want. Migratory birds leave on their own schedule, regardless of food availability, so continued feeding will not prevent birds from migrating as they should.
Squirrels not only jump well, they are quite acrobatic and can climb over almost anything. There are feeders you can buy that close under a squirrel's weight. These sometimes work unless a squirrel figures out how to bypass the closure system. There are also feeders enclosed in a cage that allows smaller birds through that work very well.
The only sure way to keep squirrels off of a conventional feeder is to place it atop a pole, 20 feet or more from a branch or roof, and attach a metal "squirrel guard" (stovepipe-like tube or cone-shaped baffle) just below the feeder. Raccoons can't jump as well, but are great climbers and need a similar guard to keep them from climbing up the pole. A stove-pipe type of raccoon guard needs to be a little longer than one for squirrels. Many people also put out food for the mammals to reduce their interest in feeders.
Peanut butter, by itself, is not harmful to birds. Some people dilute it with birdseed or cornmeal to reduce its stickiness, but that is not necessary. Uncooked rice is also not harmful. Uncooked grains are a staple for the diet of species of many birds, so throwing rice at weddings is not going to harm any birds.
Robins often stay in the vicinity of their breeding area for the winter, or may move about a several-state area in flocks. They are generally eating lots of berries, so often aren't hanging around backyards like they do the rest of the year. Like all birds, their feathers and fat reserves keep them warm for the winter, as long as they are finding food. During a snowstorm, they may "lay low" to conserve energy until the storm passes, then resume their travels in search of food. Although they don't need us to provide food during inclement weather, they seem to appreciate a heated birdbath as other water sources may be frozen or covered over temporarily.
The first step is to determine the bird's age. While many people assume a feathered bird that cannot fly has 'fallen from the nest', this may not be true. Many kinds of birds such as American Robins continue to care for their young once they leave the nest and before they fly well. If a bird has feathers and is able to hop around on the ground, it is likely a fledgling and its parents are probably nearby. Spend some time (even up to an hour) watching for the bird's parents. It is ALWAYS best to leave offspring with their parents if it is at all possible. If you think it is a fledgling, leave the bird alone. However, if you are concerned about the bird's safety, evaluate the situation and decide what is best for the bird. Placing a bird up in a shrub or in a safer spot very nearby may be the best option. Touching a bird will not cause parents to abandon it. Please keep pets and children away from the bird while it tries out its flight skills!
If the bird is naked, has very few feathers, or has its eyes closed, it is likely a nestling. If possible, try to locate the nest by looking in nearby shrubs, trees, or potted plants. Returning the nestling to its nest is by far the best solution. Many people believe that once humans touch a bird, the parents will not take care of it. Most birds have a very poorly developed sense of smell, and they will not reject their young if you handle them. They have invested a great deal of time and energy in their offspring!
Sometimes nests are destroyed in bad weather or by predators. At times, putting nestlings back into a nest is impossible because it is too high. Again, the best scenario is to try and leave these nestlings under the care of their parents. One option is to create a make-shift nest with a plastic butter tub (with holes punched in the bottom to drain water) or a berry basket. If the nest is still intact, place the nest in the basket or tub and replace babies. If the nest is gone, line the new 'nest' with dry paper towels and put young inside. Use wire to place the nest as close to the old nest as possible in a tree or in a shrub and try to give it some cover to avoid sunlight and rain. Watch to see if parents relocate the young in the new nest you have created.
While it is better to let nature take its course, a last resort measure is to contact a licensedwildlife rehabilitator to take care of a young or injured bird until it is ready for release. Bird rehabilitators are required to have a federal permit to take care of birds. Migratory birds are protected, and it is against the law to possess eggs, birds, nests, or feathers without a permit. Additionally, trying to hand raise a baby bird is an incredible task, and requires a great deal of time, effort, and specialized information. Please do NOT attempt to raise a baby bird yourself. Keep in mind that rehabilitators are volunteers and do not have any obligation to take on caring for a baby or injured bird.