KONY 2012, the most viral video of all time, took the web by storm in March. Yet KONY 2012 couldn’t sustain its momentous social buzz until its day of action on April 20, called Cover the Night.

Kony-related topics received 74,000 total Twitter mentions on April 20 — less than half the level of buzz ten days after the video’s initial release on March 5.

Social intelligence engine Topsy Labs graphed the Twitter chatter around KONY 2012 and related hashtags and topics including Kony, #Kony2012, #StopKony, #CoverTheNight, LRA and Joseph Kony. Despite the film’s promotion of Cover the Night, Twitter did not buzz the way it did last month.

The chart below shows the decline of Kony-related topics since March 15:

Since early March, Topsy has recorded more than 12.5 million Twitter mentions about Joseph Kony and the Invisible Children film. The most popular terms have been Kony (6 million mentions) and #Kony2012 (4 million mentions). The two biggest days for tweets were March 5, when the film was released and March 16, when director Jason Russell was arrested.

The below chart shows the Twitter buzz since KONY 2012 was released March 5, which places into perspective the tapering of online discussions.

There were 12 million mentions of Kony-related topics in March, compared to less than half a million mentions during the first 18 days of April.

Do you think Cover the Night would have been more successful had it come closer to the video’s release? Do you think there’s any way to sustain a viral cause campaign longterm? Sound off in the comments.

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