The song of a cuckoo is often described as a distinctive and melodious "cuck-oo" sound, which gives the bird its name. It's a repetitive and easily recognizable , typically consisting of two notes, with the second note slightly lower in pitch. The male cuckoo's song is used primarily for territorial defense and attracting mates during the breeding season. Interestingly, the cuckoo is known for its unique breeding strategy of laying eggs in the nests of other bird species, relying on their parental care to raise its young.