The article presents the results from a systematic observation of and interviews with journalists who produce local radio news program, BandNews FM, in Rio de Janeiro. The objective is to analyze how the gatewatching process is applied to selecting sources from WhatsApp, and to explore the specific nature of work carried out in radio journalism newsrooms. One of the main features of this broadcaster is the large number of public voices selected from the WhatsApp instant messaging application. The data shows popular voices selected for this paper which fit into a particular theme, it shows the collaborative curation with listeners, and it shows the organizational constraints of investigation, highlighted by journalists sitting behind a desk, absent from the stage of the events. Unlike other media vehicles, radio demands continuous updating and decentralization when selecting material to be broadcast. This study points out characteristics that are demanded of journalists who work in radio and the new, newsroom strategies of involving the public via social networking platforms.