MySpace co-president Jason Hirschhorn is reportedly out at the News Corp. subsidiary after 16 months. In the same timeframe, his ailing social network lost its founder, its CEO, an incubator — and a whole lot of traffic.

Both TechCrunch and Business Insider are reporting that MTV and Sling Media veteran Hirschhorn is exiting MySpace; TechCrunch says the announcement is coming tomorrow, and Insider states he'll be moving back to New York from MySpace's Los Angeles office. Hirschhorn got entangled in the geographic power struggle that saw CEO Owen Van Natta ousted in February. Hirschhorn had been threatening to walk before Van Natta left; whether Hirshorn finally carried out that threat or got caught in a political fight of his own isn't clear, but, given the MySpace traffic trend starkly illustrated in the Quantcast chart below, that question seems increasingly irrelevant. MySpace is withering.

[Top pic: Hirschhorn by Rex Hammock]