CalMac has reported a "small but worrying increase" in incidents of verbal or physical abuse in the past six months.
The ferry operator is launching a new campaign to reinforce its zero tolerance policy of unacceptable behaviour.
A new CalMac website outlining real life incidents and the consequences of them has now gone live. In one of the incidents, a verbally abusive man jumped up onto the counter to reach the staff on the other side. The police were called and the man arrested.
CalMac runs a fleet of 32 vessels across a network of 27 islands and remote mainland destinations. Last year it carried more than five million passengers and 1.2 million vehicles.
CalMac's director of safety, environment and security, Louis de Wolff said: "Safety of our staff is a priority for us and recently we have seen a small upsurge of abusive passengers behaving in an intolerable way towards staff, this is unacceptable. With people out and about socialising more over the festive period we felt this was a good time to reinforce the standards of behaviour we expect passengers to have towards our staff.
"Being a lifeline service we understand the importance of our sailings to customers and that they may become frustrated if the service does not go to plan, often because of circumstances outwith our control."
"This is never a reason to become abusive or worse. This is a very small minority of passengers but we feel we need to highlight that we will not tolerate any instance of work related violence, including verbal abuse, to our staff. Prosecution is a last resort but it is something we will consider if necessary and have had reason to proceed with in the past."
Other options for dealing with customers displaying abusive behaviour include not allowing the customer to board, banning a customer from sailing for a specific time period and requesting the police remove individuals from company premises.