A method for improving the reliability of sound broadcast systems used in ecological research and management

Abstract

Automated sound broadcast systems have been used to address a variety of ecological questions, and show great potential as a management tool. Such systems need to be reliable because treatments are often applied in the absence of a human observer and system failure can cause methodological ambiguity. During the breeding seasons of 2012 and 2013, we used a sound broadcast system previously described by Farrell and Campomizzi (2011) in an experiment evaluating the use of post-breeding song in forest-bird habitat selection in southern Indiana, USA. This system incorporates a portable compact disc (CD) player where the play button is permanently depressed using manual compression so that when a timer connects an electrical current to the unit, the CD player automatically starts. Despite exhaustive efforts to find a reliable way to manually compress the play button on numerous CD player models, play button failure was the most significant source of broadcast system failure (88%) in 2012. We attempted to resolve this problem in 2013 by removing the need for manual compression and soldering the play button contact poles on each CD players' integrated circuit boards. Though we did experience broadcast system failures during <5% of treatment periods in 2013, none of those were attributable to play button failure. By removing all possibility of failure from manual play button compression we improved our system reliability. Thus, soldering the CD player play button on such broadcast systems represents a methodological improvement that can be used by researchers and managers interested in sound broadcast. © 2014 The Wildlife Society.