This paper examines how social networks can be used to recruit and promote a crowdsourced citizen science project and compares this recruiting method to the use of traditional media channels including press releases, news stories, and participation campaigns. The target studied is Creek Watch, a citizen science project that allows anyone with an iPhone to submit photos and observations of their local waterways to authorities who use the data for water management, environmental programs, and cleanup events. The results compare promotional campaigns using a traditional press release with news pickups, a participation campaign through local organizations, and a social networking campaign through Facebook and Twitter. Results also include the trial of a feature that allows users to post automatically to Facebook or Twitter. Social networking is found to be a worthwhile avenue for increasing awareness of the project, increasing the conversion rate from browsers to participants, but that targeting existing communities with a participation campaign was a more successful means for increasing the amount of data collected by volunteers. Copyright 2013 ACM.