Fans of SeaWorld may have noticed something interesting if they checked out the “Event” page for the park’s “Bands, Brew, & BBQ” music series. A cached snapshot of the page from Dec. 4 features the following list:

· Saturday, February 1 Willie Nelson

· Sunday, February 2 Coming Soon

· Saturday, February 8 Cheap Trick

· Sunday, February 9 Coming Soon

· Saturday, February 15 Coming Soon

· Sunday, February 16 REO Speedwagon

· Saturday, February 22 Coming Soon

· Sunday, February 23 Justin Moore

· Saturday, March 1 Scotty McCreery

· Sunday, March 2 Coming Soon

· Saturday, March 8 Martina McBride

· Sunday, March 9 38 Special

But if you had visited the page on Tuesday morning, you wouldn’t have been able to find a schedule. It hadn’t been replaced, simply excised.

It’s telling, because in the past few weeks, three acts have canceled their appearances: Willie Nelson, The Barenaked Ladies, and Heart.

The Barenaked Ladies were first, announcing their decision at the end of November, a few days after viewing the documentary Blackfish. There was also a petition on change.org entitled “Barenaked Ladies: Cancel Your Performance at Seaworld” that received nearly 12,000 signatures. The band also made an announcement on Facebook.

“We here at Barenaked Ladies have made a decision based on what we feel. It's not about money, or petitions, or press ... But it is about our fans. We listen to them, and they're important to us. Their sensibilities resonate with ours, and have for decades now. We've grown up together. Ultimately though, we made the decision that WE feel good about.”

Soon after, another petition appeared, asking Willie Nelson to do the same. The petition received over 9,000 signatures and his appearance was canceled as well. Although SeaWorld initially claimed that was due to “scheduling conflicts” rather than anything involving Blackfish, Nelson himself told CNN that it was because of the controversy.

"I don't agree with the way they treat their animals. It wasn't that hard a deal for me," he said.

Heart was petitoned as well, and on the seventh of December they announced via Twitter that they would be canceling as well, citing Blackfish as the catalyst.

So far, none of the other performers have canceled their performances, but there are change.org petitions going for Cheap Trick, REO Speedwagon, Trisha Yearwood, and the rest as well. Whether they ultimately decide to stay or go, it’s unlikely that they will stay silent much longer. With more than a month and half to go before the music series is set to start, there’s plenty more time for controversy.