Every Russian opposition rally and march attracts wild online speculation about the numbers of participants — both by observers and the participants themselves. This week's May 6 rally commemorating last year's event which ended in violence and arrests (the so-called Bolotnaya prisoners) was no exception.

As usual, the estimates ranged widely even before the scheduled start of the rally at 7:00 PM. At 6:38 PM journalist Alina Grebneva tweeted [ru] that she thought there were 2.5 thousand people present. Just two minutes later she tweeted again [ru] that another journalist next to her estimated 5 or 6 thousand. Around the same time, at 6:46 PM, Coordinating Council member Ilya Yashin estimated [ru] that there were already 30,000 participants.

Journalist Oleg Kashin singing cult punk classic “Everything is According to Plan” in lieu of a speech at the May 6, 2013 rally in Moscow. YouTube screenshot, May 6, 2013.

The next batch of estimates came after 7:00 PM: first, at 7:06 PM leftist leader Sergey Udaltsov (who is under house arrest, and therefore was not actually present at the rally) tweeted [ru] that there were 50,000 people, Yashin repeated [ru] this figure at 7:10. Meanwhile, by 7:26 PM Grebneva updated her estimate [ru] to 10,000. At around the same time Moscow police low-balled with an estimate [ru] of 7 thousand people passing their metal detector checkpoints, while Radio Svoboda said [ru] that the “consensus” seemed to be around 15-20 thousand. At 7:46 PM Echo Moskvy's Alexey Venediktov did some “math” based on the area of the Bolotnaya Square and arrived at anywhere from 28 to 42 thousand people (at 2 and 3 people per square meter).

Of course, all of these numbers were pure guesswork (doubly so on Udaltsov's part). It is extremely hard to judge the size of a crowd even with a bird's eye view, harder still when you are actually part of the crowd, or looking at it from one side — which is the reason why such estimates always vary widely (one is reminded of journalist Oleg Kozyrev's tweets about hundreds of thousands of participants at one of the prior marches). What is surprising is the ease with which the people guesstimating could arrive at a reasonably accurate number, if only they were willing to put in the time.

SONAR's website. Screenshot, May 6, 2013.

Enter SONAR [ru], a group of electoral observer volunteers, who have organized a hand count of rally participants using tally counters (RuNet Echo has previously reported [ru] on their attempts to arrive at accurate rally counts). SONAR has been tweeting [ru] and updating its Facebook page [ru] live, as the results came in, and it is interesting to compare these results to the various numbers thrown around on Twitter.

At 6:30 PM SONAR counted 7,000, by 7:00 PM the number grew to 13,900 — a far cry from 30,000 first estimated by Yashin, but already higher than the final police estimate. At 7:30 SONAR counted 22,100 people, a number which oddly continued growing until the rally ended at 8:30, with 27,500. It is unclear if the count reflects a lag in reporting, or if there were indeed 5 thousand stragglers who showed up to see the last few minutes of speeches (and missed Oleg Kashin's singing). Although the final number will probably upset both supporters and detractors of the protest cause, it appear to be relatively accurate, as it is in line with some of the saner estimates. Incidentally, SONAR has shown once again that a simple averaging of highest and lowest estimates often works perfectly — Yashin's 50,000 plus the police's 7,000, divided by 2, is 28,500 people.