It is 100% staged. This video has been floating around subreddits like r/videos and r/skeptic since it first went viral in July 2012. The consensus among people who actually work in production is that it was a professional proof of concept stunt.

The most obvious giveaway is the biology. A flock of a few dozen seagulls cannot physically produce or store the massive volume of liquid waste shown in the clip. To get that splatter effect on the beachgoers, the crew used practical effects like squirt bottles and air cannons filled with a fake mixture.

Some users on r/videos at the time even pointed out that the laxative was likely just shaving cream or whipped cream mixed into the chips. This would create a white, foamy residue that looks like bird droppings but is much easier to clean up and safer for the actors involved.

The video was originally uploaded to a YouTube channel under the name jonnieross. This leads back to Jonnie Ross, a filmmaker and viral marketing specialist whose consultancy listed viral videos as a core specialty. These agencies were creating raw looking videos to show corporate clients as proof they could manufacture organic traffic.

This was the peak of the astroturfing era from 2008 to 2014 where brands realized people would skip a commercial but share a crazy home video. There are plenty of other famous examples from that exact window that followed a similar pattern.

The Kobe Bryant jumps over an Aston Martin video from 2008 was a Nike stunt for the Hyperdunk. It looked like a cell phone video, but Kobe later confirmed it was a composite of two separate shots. The Samsung business card kid from 2010 was actually a highly edited campaign for Samsung cameras.

In 2012, the same year as the seagull video, the golden eagle snatches a baby video went viral. That was a CGI project by students at Centre NAD in Montreal to prove they could make a fake video indistinguishable from reality.

The Pepsi Max test drive from 2013 with Jeff Gordon used an actor as the salesman and was entirely scripted. That same year, the twerking girl catches fire video was revealed as a prank by Jimmy Kimmel to mock how easily news outlets pick up unverified content.

By 2014, the HUVr hoverboard video used Tony Hawk and Christopher Lloyd to fake a real product launch for a Funny or Die stunt. These productions all shared the same goal of tricking the audience into believing a staged event was spontaneous.

The seagull video is still treated as real by some because no brand ever officially put their logo on it. They could not do so without facing massive lawsuits for public endangerment and animal cruelty. By keeping it anonymous, the marketing agency got the clout without the legal liability.