When the kids find the web page about the lighthouse keeper's wife, there's a brief shot of the computer screen. The news page links to several other topics that sound like Syfy movies: Alligator attacks in Louisiana swamps, Ex-government scientists control weather. There's also a link to "People watching science fiction movie pause screen to read unimportant text".
The shark, made by the Shark City Ozark team, is a replica of Bruce, to pay tribute to Jaws.
According to media reports, LSU head football coach Les Miles was originally selected to play the mayor, but had to withdraw due to scheduling conflicts.