Why do some birds mimic the sounds of other species?

Along with Northern Mockingbirds, Gray Catbirds are well-known North American mimics. Photo by Jim via Birdshare. Although some birds learn their species’ song during their first year of life, others, including mockingbirds, continue adding to their repertoire as they grow older. Northern Mockingbirds can learn as many as 200 songs, and often mimic sounds in their environment including other birds, car alarms, and creaky gates. One theory is that if a female prefers males who sing more songs, a male can top his rivals by quickly adding to his repertoire some of the sounds around him. Possessing a diverse assortment of songs may indicate he is an older male with proven longevity and survival skills–good traits to pass on to offspring. An older male may also be more experienced in raising young or may have access to better resources. According to one study on the Edwards Plateau in Texas, mockingbirds with the largest repertoires have the best territories, laden with foods such as insec ... Read full article.