There are many ways to train racing pigeons. Like every sport out there, racing pigeons is an evolving sport. One of the most popular systems is widowhood. This system uses the birds' desire to reproduce as motivation to try to give the bird a sense of urgency on race day. The use of widowhood is usually begun by first allowing the racer to raise a baby in their nest box. After the baby is weaned the hen is removed and often the nestbox is closed off, from then on the only time these birds are allowed to see their mate or enter the nest box is upon returning from training or a race. This conditioning is one of the key elements in a lot of racing programs.