The New Zealand players have a protocol to follow if the abuse is getting out of hand.
Southee followed it, advising the team security personnel, who discussed the situation with ground security and the offenders were dealt with by Waca officials.
There had already been an independent complaint about two spectators before Southee raised the matter, as per security arrangements procedures. The abuse was described as ''low brow''.
It's part and parcel of playing international cricket in Australia, and something former New Zealand players could relate to. The most notable occasion was when Richard Hadlee was the target in 1987-88.
In that instance, it could be called a distinctly Australian form of admiration for a champion bowler.