"The idea behind doing this was to raise awareness amongst motorists as it's a problem in many cities around the world," he said.
"Anecdotally bus drivers tell us that in Tauranga, like other cities, motorists don't always let buses back into the flow of traffic."
Cameron Rd, Maunganui Rd and Adams Ave in Mount Maunganui were the main areas where motorists did not allow buses back on the road, the spokesman said.
A Tauranga bus driver, who spoke on the condition he was not identified for fear of losing his job, said elderly motorists and parents picking up their children were the worst offenders.
"The biggest problem is the times before and after school because all of the parents decide Little Johnny has got to be picked up in the car rather than catch the bus home.
"All of these parents in their cars, they don't care where they park to pick up their children. Then it becomes a big backlog of traffic all the way down the road. People don't want to let you back in."
The driver, who is on the road every day, said elderly drivers were "a blight on society".
"When they get out and they are not quite sure of things, they stop in the middle of the road to get their directions."
The driver said he felt the issue of "selfish" drivers was worse in Tauranga than in Auckland where public transport appeared to be more accepted.
He would like to see legislation like there is in Australia, in which drivers are fined if they fail to allow buses back into traffic. A person who does not give way to a bus in Australia could be fined $337 and three demerit points.
NZ Bus chief commercial officer Scott Thorne said letting buses back into traffic had always been a factor in running punctual and reliable bus services. It was a common issue in each city but was especially bad at this time of year, he said.
Thorne said the company and its staff were "very grateful" for the regional council's advertising.
"We are in the busiest time of year on the roads, and if all road users take heed it will really help deliver a reliable and punctual experience for our customers. This would also significantly reduce the stress that our drivers face on the road every day."