What happens when we feed birds?

Great tit males that are fed start singing later in the morning. This changes their territorial behavior - which could have implications for their reproductive success. Although about half the population feeds free-living birds in winter, the effects on their behavior have hardly been studied . When the days start to get longer again from Christmas onwards, the first great tits start to sing, and only the males, as is usual for native songbird species. Spring and the breeding season are still far away, but the animals are already practicing their song, with which they defend their territory against other males. Numerous great tit territories are located in our cities and gardens, and in many of these territories there is a feeder or tit dumplings are hung up. How feeding affects bird behavior, however, is poorly understood - yet bird feeding is probably the activity that brings most people around the world into conscious contact with wildlife. It is known that blue tits that are fed in winter lay eggs earlier in the breeding season and have more offspring than their non-fed counterparts. Increasingly, however, bird feeding is not limited to the winter, but is practiced into the spring or even throughout the year. Do females become unfaithful? Researchers have now investigated how great tit males react when bird food is offered in their territories until the beginning of April, shortly before the start of egg laying. To do this, they hung up feeders in 28 great tit territories. In half of these territories, the silos were filled with food for two weeks and titmouse dumplings were also hung up; the other half of the territories served as a control without titmouse dumplings and with empty feeders. Before the start of feeding, at the end of the two weeks of feeding and again two weeks later, the song of the males was recorded with directional microphones, one hour before and one hour after sunrise.