Swamp Sparrows

What are birds saying when they sing?
Dana Moseley, PhD student in OEB, seeks to answer this question by studying Swamp Sparrows in the Quabbin Reservoir of Massachusetts. Next to humans, birds are the best vocal communicators in the animal kingdom. Male Swamp Sparrows sing trilled songs and vary in how fast they can sing these trills. We know that sparrows learn their songs and face constraints in making a fast trill, but Dana wants to know how their song is used in sexual selection. Are females using these trills to choose their mates? Do males settle fights over territories and mates by comparing their fast songs? To understand how birds are using their songs, Dana wades through the swamp with a microphone and a recorder to capture males' natural singing behavior. With today's computer technology, she is then able to speed up or slow down recordings of swamp sparrow trills. A faster song should be more attractive to females and more threatening to males. So using portable speakers in the swamp, she is able to play these modified songs to wild males on territories and to females in the lab. By observing the birds' behavior in response to the songs, Dana hopes to determine which type of song is most effective in communicating the fitness of a male bird.