Dawn chorus (AUDIO) Duke University Your browser does not support the audio element. Caption A dawn chorus from Pymatuning marsh in northwest Pennsylvania, where the swamp sparrows were collected. Credit Stephen Nowicki, Duke University Usage Restrictions Please credit Stephen Nowicki, Duke University License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.