The demonstration followed two recent incidents involving protesters throwing eggs at King Charles III.
"Actually, we can help, you know, as individuals," Mark Spencer claimed.
Blue Shark Snorkel Trips, the company that organised the tour, said bites were "extremely rare".
Sorry, but why is Cornwall more expensive than Corfu?
Cornwall and Devon are experiencing Covid spikes, but what are the risks?
Visit Cornwall wants holidaymakers not to visit unless they have pre-booked their holidays and to test themselves before, during and after their time in the region.
It could all kick off as EU leaders arrive in Cornwall.
Experts say it's the most southerly sighting of the UK’s only resident Orca family.
Prime Minister squirms under scrutiny from Lara from Cornwall.
West Midlands mayor Andy Street leads criticism with Cornwall the only place on the English mainland to escape the worst restrictions.